DH-1.1 branch

Oligomeric or polymeric offshoot from a macromolecular chain.

1. See references [11], [12].

DH-1.2 branch constitutional repeating unit

Constitutional repeating unit of connectivity three or more connected at least to three other constitutional repeating units.

1. In addition, a branch constitutional repeating unit may also be connected to one or more end-groups.

DH-1.3 branch point

Point on a chain at which a branch is attached.

1. See references [11], [12].

DH-1.4 chain

Whole or part of a macromolecule, an oligomer molecule, or a block, comprising a linear or branched sequence of constitutional units between two boundary constitutional units, each of which may be either an end-group, a branch point or an otherwise-designated characteristic feature of the macromolecule.

1. Except in linear single-strand macromolecules, the definition of a chain may be somewhat arbitrary.

   Note 2: See references [11], [12].

DH-1.5 connectivity (of a constitutional unit), recommended symbol: c

Number of covalent bonds emanating from a constitutional unit.

1. For the purpose of determining connectivity a multiple bond is treated as one bond.

2. In most cases, the connectivity of an end-group is 1. In some exceptional cases it can be higher, for instance when two hydroxy end-groups are modified into an acetal group.

DH-1.6 constitutional repeating unit (CRU)

Smallest constitutional unit, the repetition of which constitutes a regular macromolecule, a regular oligomer molecule, a regular block, or a regular chain.

1. See references [11], [12].

DH-1.7 constitutional unit (CU)

Atom or group of atoms (with pendant atoms or groups, if any) comprising a part of the essential structure of a macromolecule, an oligomer molecule, a block, or a chain.

1. See references [11], [12].

DH-1.8 core unit

Constitutional unit in a dendrimer molecule, from which the dendron(s) emanate(s).

1. An example of a core unit in a dendrimer molecule is given in Fig. 3.

2. The structure of the core unit may be identical to that of the constitutional repeating units (See Example 6 in DH-2.10).

3. Occasionally, a dendrimer molecule may consist of two dendrons directly connected together (see also DH-1.11).

4. In a hyperbranched macromolecule obtained by the AB_x-type monomer + B_y-type monomer polycondensation approach, where A and B refer to mutually reactive groups, the terms core molecule (not acceptable) and core unit refer to the B_y-type unit, even though the structure of the macromolecule does not comprise dendrons. See Fig. 2 for the example of a hyperbranched molecule of this type.

Fig. 3:

Representation of a regular dendrimer molecule highlighting the core unit and the dendrons. This dendrimer is described in ref. [16].

DH-1.9 degree of branching, recommended symbol D_br

Parameter characterizing the branched architecture of a hyperbranched polymer, which is equal to unity for a polymer that contains no linear or semi-dendritic constitutional repeating unit and is equal to 0 for a polymer that contains no dendritic or semi-dendritic constitutional repeating unit.

1. Several definitions of the degree of branching have been proposed for hyperbranched polymers obtained by polycondensation of AB₂-type monomers [17], [18] and for those obtained by polycondensation of more complex monomer systems [18], [19], [20], [21]. The definition by Hölter et al. [18] is: D_br=2x_D/(2x_D+x_L), where x_D and x_L are the mole fractions of dendritic and linear units, respectively.

2. The degree of branching of a dendrimer is equal to one. However, a polymer with the degree of branching equal to one is not necessarily a dendrimer. It can be a hyperbranched polymer, since the degree of branching does not per se take into account the regularity and symmetry of the molecules that compose it.

3. The degree of branching of a linear polymer is equal to 0.

DH-1.10 dendrimer

Substance composed of identical dendrimer molecules.

DH-1.11 dendrimer molecule

Molecule consisting of one or more dendrons emanating from a single constitutional unit.

1. See also DH-1.8.

2. An example of a formula of a dendrimer molecule is given in Fig. 3.

3. Occasionally, a dendrimer molecule may consist of two dendrons directly connected together.

DH-1.12 dendritic block macromolecule

Block macromolecule in which at least one block is a dendron.

1. See Examples 15 and 16 in DH-2.14.

2. See the definition of block macromolecule in refs. [11], [12].

DH-1.13 dendritic constitutional repeating unit

Constitutional repeating unit of connectivity c≥3 connected to c other constitutional repeating units.

1. Examples of dendritic constitutional repeating units of connectivity c=3 connected to 3 other constitutional repeating units are given in Figs. 4 and 6. See also DH-1.17, Note 1.

2. Dendritic constitutional repeating units belong to the class of branch constitutional repeating units.

DH-1.14 dendritic graft macromolecule

Graft macromolecule in which at least one of the grafts contains a dendron.

1. See Examples 17 and 18 in DH-2.15.

2. See the definition of graft macromolecule in refs. [11], [12].

3. A dendritic graft macromolecule is sometimes referred to as a dendronised macromolecule.

DH-1.15 dendritic macromolecule

Macromolecule containing at least one dendron.

DH-1.16 dendritic polymer

Substance composed of dendritic macromolecules.

1. This definition replaces the definition of ‘dendritic polymer’ in ref. [22].

DH-1.17 dendron

Part of a molecule with only one free valence, comprising exclusively dendritic and terminal constitutional repeating units and in which each path from the free valence to any end-group comprises the same number of constitutional repeating units.

1. For the purpose of determining the nature of constitutional repeating units the free valence is treated as a connection to a CRU.

2. A dendrimer molecule comprising only one dendron is sometimes referred to as dendron, monodendron or functionalised dendron. The use of the terms ‘dendron’ or ‘monodendron’ in the meaning of molecule or substance is not acceptable. See also DH-1.11.

3. In a dendron, macrocycles of constitutional units are absent (See Fig. 4).

Fig. 4:

Example of a regular dendron, highlighting dendritic constitutional repeating units, terminal constitutional repeating units, end-groups, the dendron direction and the free valence. The preferred constitutional repeating unit is chosen according to rule DH-2.2.

DH-1.18 dendron direction

For a constitutional repeating unit of a dendron, the direction from the free valence to the end-groups.

1. See Fig. 4.

DH-1.19 end-group

Constitutional unit that is an extremity of a macromolecule or oligomer molecule.

1. An end-group is attached to only one constitutional unit of a macromolecule or oligomer molecule (See Figs. 4–6).

2. Exceptionally end-groups can be single atoms, such as hydrogen atoms (Fig. 4).

3. See references [11], [12].

Fig. 5:

Example of a four-generation dendron, highlighting constitutional repeating units of generations 1 to 4 and the end-groups. The preferred constitutional repeating unit is chosen according to rule DH-2.2.

Fig. 6:

Examples of hyperbranched molecules with a core unit. Terminal, linear and dendritic constitutional repeating units and the core unit are circled. The preferred constitutional repeating unit is chosen according to rule DH-2.2.

DH-1.20 focal unit

Core unit of a dendrimer molecule that comprises only one dendron

DH-1.21 generation (in a dendron)

Set of constitutional repeating units separated from the free valence of a dendron by the same number of constitutional repeating units.

1. Generations are numbered consecutively starting from the constitutional repeating unit bearing the free valence (See Fig. 5).

DH-1.22 hyperbranched macromolecule

Highly branched macromolecule, the constitutional repeating units of which are in substantial part branch constitutional repeating units and terminal constitutional repeating units.

1. Hyperbranched macromolecules, unlike dendrimer molecules, usually comprise a number of randomly distributed linear constitutional repeating units (see Fig. 6).

2. For the purpose of determining the type of constitutional repeating units (dendritic, semi-dendritic, terminal or linear CRUs) in a hyperbranched macromolecule, the core unit should be treated as a CRU.

DH-1.23 hyperbranched oligomer

Substance composed of hyperbranched oligomer molecules.

DH-1.24 hyperbranched oligomer molecule

Highly branched oligomer molecule, the constitutional repeating units of which are in substantial part branch constitutional repeating units and terminal constitutional repeating units.

1. See also DH-1.22, Notes 1 and 2.

DH-1.25 hyperbranched polymer

Substance composed of hyperbranched macromolecules.

1. The term ‘dendrigraft’ is sometimes used for hyperbranched polymers of low molar-mass-dispersity. The use of ‘dendrigraft’ is not acceptable.

2. The present definition replaces the definition in the Glossary of Class Names of Polymers [22].

DH-1.26 irregular dendrimer

Substance composed of irregular dendrimer molecules.

DH-1.27 irregular dendrimer molecule

Dendrimer molecule that contains either different types of regular dendrons or at least one irregular dendron.

DH-1.28 irregular dendron

Dendron composed of either different types of constitutional units, different types of end-groups or any combination of these.

DH-1.29 irregular macromolecule

Macromolecule, the structure of which essentially comprises the repetition of more than one type of constitutional unit, or a macromolecule, the structure of which comprises constitutional units not all connected identically with respect to directional sense.

1. See references [11], [12].

DH-1.30 linear constitutional repeating unit

Constitutional repeating unit connected to exactly two other constitutional repeating units.

1. See Fig. 6.

2. A linear constitutional repeating unit may be connected to one or more end-groups.

3. End-groups attached to non-terminal constitutional repeating units are sometimes termed side groups. The use of the term side group in this meaning is not acceptable.

DH-1.31 macromolecule

polymer molecule

Molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass.

1. In many cases, especially for synthetic polymers, a molecule can be regarded as having a high relative molecular mass if the addition or removal of one or a few of the units has a negligible effect on the molecular properties. This statement fails in the case of certain properties of macromolecules, which may be critically dependent on fine details of the molecular structure, e.g., the enzymatic properties of polypeptides.

2. See references [11], [12].

DH-1.32 monomer molecule

A molecule which can undergo polymerization, thereby contributing constitutional units to the essential structure of a macromolecule.

1. See references [11], [12].

DH-1.33 number of generations (of a dendron), recommended symbol G

Number of constitutional repeating units on the path from the free valence to any end-group of a dendron.

1. The number of generations G is a cardinal number. A dendron with G=n generations of constitutional repeating units should be called n-generation dendron. The terms dendron of n^th generation or n^th generation dendron are not acceptable.

DH-1.34 number of generations (of a regular dendrimer molecule), recommended symbol G

Number of generation of the dendrons of a regular dendrimer molecule.

1. See DH-1.33.

DH-1.35 number of pseudo-generations (of a hyperbranched polymer)

Number of generations of the hypothetical dendrimer molecule that would present the same ratio of constitutional repeating units to core unit.

1. The number of pseudo-generations can be a decimal number, while the number of generations of a dendrimer molecule is an integer.

2. In hyperbranched polymers obtained by the AB_x-type monomer+B_y-type monomer polycondensation approach, where A and B represent mutually reactive groups, the number of pseudo-generations n can be calculated by solving the equation:

   r = y ( x n − 1 ) / ( x − 1 ) ,

   where r is the mole ratio of AB_x-type monomer to B_y-type monomer in the initial monomer mixture. See Fig. 2 for an example of AB₂ and B₃-type monomers (x=2 and y=3).

3. The use of the terms generation and number of generations for a hyperbranched polymer is not acceptable.

DH-1.36 oligomer

Substance composed of oligomer molecules.

1. See references [11], [12].

DH-1.37 oligomer molecule

Molecule of intermediate relative molecular mass, the structure of which essentially comprises a small plurality of units derived, actually or conceptually, from molecules of lower relative molecular mass.

1. A molecule is regarded as having an intermediate relative molecular mass if it has properties which do vary significantly with the removal of one or a few of the units.

2. See references [11], [12].

DH-1.38 polymer

Substance composed of macromolecules.

1. See references [11], [12].

DH-1.39 regular dendrimer

Substance composed of regular dendrimer molecules.

DH-1.40 regular dendrimer molecule

Dendrimer molecule comprising only identical regular dendrons.

1. A dendrimer molecule comprising only one dendron is a regular dendrimer molecule.

DH-1.41 regular dendron

Dendron composed of only one type of constitutional repeating units and of only one type of end-groups.

DH-1.42 regular macromolecule

Macromolecule, the structure of which essentially comprises the repetition of a single constitutional unit with all units connected identically with respect to directional sense.

1. See references [11], [12].

DH-1.43 semi-dendritic constitutional repeating unit

Constitutional repeating unit of connectivity c≥4 connected to more than 2 but less than c other constitutional repeating units.

1. See Fig. 7.

Fig. 7:

Example of a hyperbranched macromolecule part with a semi-dendritic constitutional repeating unit of connectivity c=4 (circled), connected to 3 other constitutional repeating units and to one hydroxymethyl end-group. The preferred constitutional repeating unit is chosen according to rule DH-2.2.

DH-1.44 terminal constitutional repeating unit

Constitutional repeating unit connected to only one other constitutional repeating unit.

1. See Figs. 4 and 6.

2. A terminal constitutional repeating unit may be connected to one or more end-groups.

DH-2.0 General principles

Dendrimers can be named in two ways:

1. by a form of organic chemistry multiplicative nomenclature [15] in which the core unit is a multivalent substituent and dendrons are multiple parent structures,

2. by a form of organic chemistry substitutive nomenclature [15] in which the core unit is chosen as parent structure and dendrons are attached to it.

These two naming systems are extensions of existing polymer nomenclature rules for star polymers (rules 21 and 22 in [9], [12]).

DH-2.1 Choice of multiplicative vs. substitutive dendrimer nomenclature

DH-2.1.1 Multiplicative dendrimer nomenclature is preferred for most regular dendrimers, i.e.:

1. regular dendrimers with a monovalent core unit.

2. regular dendrimers with a multivalent simple core unit, i.e. a core unit consisting of a simple multivalent component (e.g. –O–, –CH₂–, –N<, benzene-1,3,5-triyl, –CH₂–CH₂–), which may be substituted [e.g. –CH(CH₃)–CH₂–].

3. regular dendrimers with a multivalent multipart symmetrical core unit, i.e. a core unit composed of concatenated simple multivalent components [e.g. –CH₂–O–CH₂–, N(CH₂–CH₂–)₃]. Substitution is allowed provided that the sequence of component units, starting from the central one, is identical in each of the branches.

1. DH-2.1.1 essentially applies to dendrimers the general principles of organic chemistry multiplicative nomenclature, as detailed in P-15.3 [15].

DH-2.1.2 Multiplicative dendrimer nomenclature cannot be applied to regular dendrimers with multipart unsymmetrical core units, or to regular dendrimers with unsymmetrical core units having different types of bonds (single/multiple), or to regular dendrimers with symmetrical multipart core units composed of unsymmetrically substituted component units or to irregular dendrimers.

DH-2.1.3 Substitutive dendrimer nomenclature can be applied to any type of dendrimer or dendritic polymer and is the only one allowed for dendrimers of types other than those specified in DH-2.1.1.

1. In dendrimer substitutive nomenclature, the core unit is always the parent structure.

DH-2.1.4 Naming a dendrimer by either type of nomenclature comprises the following steps:

1. identification of the overall structure of the dendrimer molecule: dendrons and core unit,

2. choice of the preferred CRU(s),

3. choice of the preferred end-group(s),

4. choice of the preferred core unit and determination of its type (symmetrical or not, substituted or not),

5. determination of the dendrimer type (regular, irregular) and of the number of generations of dendrons,

6. naming the dendron(s),

7. naming the dendrimer using multiplicative or substitutive nomenclature, depending on the core unit and dendrimer types.

DH-2.2 Choice of the preferred constitutional repeating unit (CRU) of a dendron

The preferred constitutional repeating unit of a dendron is chosen in such a way that the branch points be at its end in the dendron direction.

1. Dendron direction is defined in DH-1.18.

DH-2.3 Choice of the preferred end-groups of a dendron

After the preferred constitutional repeating unit of a dendron has been defined, the preferred end-groups are chosen to maximize the number of generations of the dendron.

DH-2.4 Choice of the preferred core unit of a dendrimer molecule

After the preferred constitutional repeating unit and the preferred end-groups of the dendrons of a dendrimer have been defined, the preferred core unit is chosen to maximize the number of generations of the dendrons.

DH-2.5 Naming the preferred constitutional repeating unit (CRU) of a dendron

DH-2.5.1 The preferred constitutional repeating unit is named according to polymer nomenclature rules [12], [13], by citing consecutively concatenated components in the dendron direction, the branch component being named last.

1. Dendron direction is defined in DH-1.18

2. Polymer nomenclature includes the following differences from organic-chemical nomenclature [13]:

   1. ethylene is used as preferred name for –CH₂–CH₂– instead of ethane-1,2-diyl [13], [23].

   2. pendant groups, i.e. groups of atoms that are not part of the main chain, must be regarded as substituents, e.g. in a polymer chain, –CH(CH₃)–CH₂– is 1-methylethylene, not propane-1,2-diyl.

DH-2.5.2 In a component of a dendrimer CRU, the lowest locant consistent with a possibly fixed numbering of a component is assigned to the atom that is closest to the dendron free valence. Atoms are numbered and cited in ascending order in the dendron direction.

DH-2.5.3 The name of the preferred CRU remains the same in dendrimer multiplicative and substitutive nomenclature, i.e. it is not reversed when dendrons are regarded as substituents (see DH-2.9.2).

DH-2.5.4 Examples of CRU names

In the following examples, the dendron direction is from left to right.

	oxycarbonylazanediylbenzene-1,3,5-triyl Note: Locants are assigned and cited in the dendron direction.
	nonane-1,9,9,9-tetrayl Note: Branch point is numbered last in the dendron direction.
	propane-1,3-diylnitrilo Note: Locants are assigned and cited in the dendron direction (1→3).
	oxycarbonylbenzene-1,3,5-triylbis(carbonyloxybenzene-1,3,5-triyl)
	methyleneoxy(2-methyl-1-oxoethane-1,2,2-triyl) Note: Branch point is numbered and cited last (locant 2). The oxo-substituted carbon (locant 1) is cited after methyl, in alphabetic order. According to polymer nomenclature, the branch component should not be named 1-oxopropane-1,2,2-triyl, since the methyl group is a substituent of the main chain.
	azanediyl(1-oxohexane-1,2,6-triyl)
	oxy(methylsilanetriyl)
	oxymethylenebenzene-1,3,5-triyl
	methyleneoxy(3-oxopropane-1,3-diyl)azanediylmethanetetrayl Note: The oxo substituent is on the last carbon of propane-1,3-diyl component, according to the dendron direction.

DH-2.6 Naming the end-groups

The end-groups are named substitutively, according to the nomenclature of organic chemistry [15].

Examples:

DH-2.7 Naming the preferred core unit of a dendrimer molecule in multiplicative nomenclature

DH-2.7.1 In dendrimer multiplicative nomenclature, the preferred core unit is regarded as a multivalent substituent of multiple parent structures, the dendrons, and is named according to the rules of organic chemistry multiplicative nomenclature (see P-15.3 [15]).

DH-2.7.2 Concatenation is the method used for the formation of multipart multivalent core unit names. The central multivalent component is cited first, followed by a multiplicative prefix such as di-, tri-, etc., or bis-, tris- etc., and then, in order and in the dendron direction, the names of the successive di- or polyvalent substituent components. When two or more successive multiplicative groups follow the central multivalent component they are not prefixed by separate multiplicative prefixes, e.g. ethane-1,1,1-triyltris(4,1-phenyleneoxy), not ethane-1,1,1-triyltris(4,1-phenylene)tris(oxy).

DH-2.7.3 Numbering of the components of a core unit, when necessary, is achieved by attributing the lowest locants, consistent with a possibly fixed numbering of a component, to the atoms that are at the end of the component, i.e. nearest to the dendron(s). The locants for the points of attachment of the dendrons are cited last. When there is a choice, locants are cited in increasing numerical order.

DH-2.7.4 Names that are preferred in polymer structure-based nomenclature [13] should be used, e.g. ethylene instead of ethane-1,2-diyl.

DH-2.7.5 Examples of core unit names in dendrimer multiplicative nomenclature

1. Monovalent and multivalent simple core units:

   

2. Multivalent substituted simple core units:

   

3. Symmetrical complex core units:

   

4. Unsymmetrical complex core units

   

DH-2.8 Naming the preferred core unit of a dendrimer molecule in substitutive nomenclature

In substitutive nomenclature, the parent hydride corresponding to simple core units or the parent hydride corresponding to the central multivalent component of multipart core units are chosen as parent structures and named according to the nomenclature of organic chemistry [15].

1. Names preferred in polymer structure-based nomenclature [13] should be used, e.g. ethylene instead of ethane-1,2-diyl.

DH-2.9 Naming a regular dendron

DH-2.9.1 In multiplicative nomenclature, a regular dendron is named by citing the name of the end-groups preceded by ω-, followed by the italicized prefix -dendro^Gn-, where n is the number of generations of the dendron, and the parenthesized name of the preferred constitutional repeating unit. The number of end-groups is indicated by a numerical prefix (di-, tri-, etc. or bis, tris, tetrakis, etc.) before the name of the end-groups. The dendron name is enclosed in parentheses, brackets or braces, as appropriate:

[ω-numerical_prefix(end-group name)-dendro^Gn-(CRU name)]

DH-2.9.2 In substitutive nomenclature, the dendron name is followed by -α-yl, indicating that its senior end (the free valence) is connected to the parent structure (core unit or polymer chain). The CRU name is the same as that defined in multiplicative nomenclature.

[ω-numerical_prefix(end-group name)-dendro^Gn-(CRU name)-α-yl]

DH-2.10 Naming regular dendrimers with a symmetrical core unit

DH-2.10.1 Multiplicative nomenclature

In multiplicative nomenclature, a regular dendrimer is named by citing in order the name of the core unit preceded by α,α′,α″,…-, depending on the number of dendrons, a numerical prefix (bis, tris, etc.) indicating the number of dendrons, followed by the name of the dendron(s).

α,α′,α″,…-(core unit name)numerical_prefix(dendron name)

DH-2.10.2 Substitutive nomenclature

In substitutive nomenclature, a dendrimer is named as the dendron-substituted parent hydride of the innermost core component (DH-2.8), according to organic-chemical nomenclature rules [15]. Dendrons and substituents are cited in alphabetical order. The name for a substituent or a dendron is considered to begin with the first letter of its complete name, including numerical prefixes which are part of the name. Numerical prefixes multiplying a complete substituent or dendron are, however, not taken into account, as those do not belong to their name (see P-14.5 [15]).

locants-numerical_prefix[(dendron name)-α-yl]core_component_parent_hydride_name

1. “Dendron name” is the same in multiplicative and in substitutive nomenclature. In substitutive nomenclature “dendron name” is followed by the -α-yl suffix (see DH-2.9.2).

Example 1. Poly(benzyl ether)-type dendrimer with one regular dendron and a monovalent simple core unit (Fig. 8).

Fig. 8:

Poly(benzyl ether)-type dendrimer with one regular dendron and a monovalent simple core unit described in ref. [24].

The preferred CRU is oxymethylenebenzene-1,3,5-triyl (branch points last and locants cited in the dendron direction). The preferred core unit is a single hydrogen atom and the benzyloxy end-groups must be considered as composed of one CRU and two hydro end-groups, since this leads to a higher number of generations (G=4). Multiplicative nomenclature is preferred:

α-hydro-[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)]

In order to name this dendrimer by substitutive nomenclature, one CRU should be included in the core unit since substitution to hydrogen is not possible. Consequently, the dendrimer should be regarded as formed of two 3-generation dendrons and a substituted simple core unit, phenylmethanol.

{3,5-bis[ω-octahydro-dendro^G3-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}methanol

Example 2. Regular 4-dendron poly(azetidine)-type dendrimer (Fig. 9).

Fig. 9:

Regular 4-dendron poly(azetidine)-type dendrimer described in ref. [25].

The preferred CRU is propane-1,3-diylnitrilo (branch point last), leading to 2-cyanoethyl end-groups and to a propane-1,3-diyldinitrilo symmetrical core unit. G=4 for each dendron. Dendrimer multiplicative nomenclature is preferred:

α,α′,α″,α′′′-(propane-1,3-diyldinitrilo)tetrakis[ω-hexadecakis(2-cyanoethyl)- dendro^G4-(propane-1,3-diylnitrilo)]

Dendrimer substitutive nomenclature name:

N ¹,N¹,N³,N³-tetrakis[ω-hexadecakis(2-cyanoethyl)-dendro^G4-(propane-1,3-diylnitrilo)-α-yl]propane- 1,3-diamine

Example 3. Regular 3-dendron poly(benzyl ether)-type dendrimer (Fig. 10).

Fig. 10:

Regular 3-dendron poly(benzyl ether)-type dendrimer described in ref. [16].

The preferred CRU is oxymethylenebenzene-1,3,5-triyl (branch point last), leading to the ethane-1,1,1-triyltri(4,1-phenylene) core unit. The benzyloxy end-groups must be considered as composed of an oxymethylenebenzene-1,3,5-triyl CRU and 2 hydro end-groups each, since this leads to a higher number of generations for each dendron (G=4). Dendrimer multiplicative nomenclature is preferred:

α,α′,α″-[ethane-1,1,1-triyltri(4,1-phenylene)]tris[ω-hexadecahydro-dendro^G4- (oxymethylenebenzene-1,3,5-triyl)]

Dendrimer substitutive nomenclature name:

1,1,1-tris{4-[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}ethane

Example 4. Regular 3-dendron poly(amidoamine)-type dendrimer (Fig. 11).

Fig. 11:

Regular 3-dendron poly(amidoamine)-type dendrimer (PAMAM) described in ref. [3].

The preferred CRU is (3-oxopropane-1,3-diyl)azanediylethylenenitrilo, leading to hydro end-groups and a nitrilo core (G=4). Dendrimer multiplicative nomenclature is preferred:

α,α′,α″-nitrilotris{ω-hexadecahydro-dendro^G4-[(3-oxopropane-1,3-diyl)azanediylethylenenitrilo]}

Dendrimer substitutive nomenclature can also be applied:

tris{ω-hexadecahydro-dendro^G4-[(3-oxopropane-1,3-diyl)azanediylethylenenitrilo]-α-yl}azane

Example 5. Regular 4-dendron poly(ether amido)-type dendrimer (Fig. 12).

Fig. 12:

Regular 4-dendron poly(ether amido)-type dendrimer described in ref. [26].

The preferred CRU is methyleneoxy(3-oxopropane-1,3-diyl)azanediylmethanetetrayl (branch points last). This leads to a methanetetrayl symmetrical core unit and to (2-carboxyethoxy)methyl end-groups (G=2). Dendrimer multiplicative nomenclature is preferred:

α,α′,α′′,α′′′-(methanetetrayl)tetrakis{ω-nonakis[(2-carboxyethoxy)methyl]- dendro^G2-[methyleneoxy(3-oxopropane-1,3-diyl)azanediylmethanetetrayl]}

Dendrimer substitutive nomenclature name:

tetrakis{ω-nonakis[(2-carboxyethoxy)methyl]-dendro^G2-[methyleneoxy (3-oxopropane-1,3-diyl)azanediylmethanetetrayl]-α-yl}methane

Example 6. Regular 3-dendron dendrimer in which the core unit and CRUs have the same structure (Fig. 13).

Fig. 13:

Dendrimer with benzene-1,3,5-triyl core unit and constitutional repeating units described in ref. [27].

The preferred CRU is benzene-1,3,5-triyl, leading to a benzene-1,3,5-triyl core unit and hydro end-groups (G=4). Dendrimer multiplicative nomenclature is preferred:

α,α′,α′′-(benzene-1,3,5-triyl)tris[ω-hexadecahydro-dendro^G4-(benzene-1,3,5-triyl)]

Dendrimer substitutive nomenclature name:

1,3,5-tris[ω-hexadecahydro-dendro^G4-(benzene-1,3,5-triyl)-α-yl]benzene

Example 7. Regular 2-dendron poly(benzyl ether)-type dendrimer (Fig. 14).

Fig. 14:

Regular 2-dendron poly(benzyl ether)-type dendrimer described in ref. [28].

This dendrimer is similar to that discussed in Example 1. However, the core unit is now a substituted divalent simple core unit and the dendrimer must be regarded as a 3-generation hydro-terminated regular dendrimer with two dendrons. Dendrimer multiplicative nomenclature is preferred:

α,α′-(5-{[methyl(4-nitrophenyl)amino]methyl}-1,3-phenylene)bis[ω-octahydro- dendro^G3-(oxymethylenebenzene-1,3,5-triyl)]

The dendrons are attached to atoms 1 and 3 of the core unit (lowest locants). Numerical order 1,3 is preferred to 3,1.

Dendrimer substitutive nomenclature name:

N-({3,5-bis[ω-octahydro-dendro^G3-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}methyl)- N-methyl-4-nitroaniline

Substituent ({3,5-bis[ω-octahydro-dendro… is cited first since “bis…” alphabetizes earlier than “methyl” (DH-2.10.2)

Example 8. Regular poly(benzyl ether)-type dendrimer with a substituted divalent symmetrical core unit and two dendrons (Fig. 15).

Fig. 15:

Regular poly(benzyl ether)-type dendrimer with a substituted divalent symmetrical core unit and two dendrons described in ref. [29].

The preferred CRU is oxymethylenebenzene-1,2,3-triyl, leading to [4-(methoxycarbonyl)phenyl]methoxy end-groups and to a formyl-substituted 1,2-phenylene divalent simple core unit (G=3). Dendrimer multiplicative nomenclature is preferred:

α,α′-(3-formyl-1,2-phenylene)bis(ω-octakis{[4-(methoxycarbonyl)phenyl]methoxy}-dendro^G3-[oxymethylenebenzene-1,2,3-triyl])

Dendrimer substitutive nomenclature name:

2,3-bis(ω-octakis{[4-(methoxycarbonyl)phenyl]methoxy}-dendro^G3- [oxymethylenebenzene-1,2,3-triyl]-α-yl)benzaldehyde

DH-2.11 Naming regular dendrimers with an unsymmetrical core unit

DH-2.11.1 Regular dendrimers with unsymmetrical core units are named by dendrimer substitutive nomenclature, as the dendron-substituted parent hydride of the innermost core component (DH-2.8, DH-2.10.2).

DH-2.11.2 Otherwise identical dendrons are cited in increasing numerical order of locants.

Example 9. Regular poly(benzyl ether)-type dendrimer with an unsymmetrical multipart core unit (Fig. 16).

Fig. 16:

Example of a regular poly(benzyl ether)-type dendrimer with an unsymmetrical multipart core unit.

This regular 3-dendron dendrimer presents an unsymmetrical multipart core unit. Substitutive nomenclature must be used:

1-{3-[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}- 1,1-bis{4-[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}ethane

The “{3-…” dendron is cited before the two “{4-…” dendrons, according to DH-2.11.2.

Example 10. Regular 6-dendron poly(benzyl ether)-type dendrimer with an unsymmetrical multipart core unit (Fig. 17).

Fig. 17:

Example of a regular 6-dendron poly(benzyl ether)-type dendrimer with an unsymmetrical multipart core unit.

This regular 6-dendron dendrimer contains an unsymmetrical core unit. Substitutive nomenclature must be used:

1,2,5-tris{3,5-bis[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}pentane

DH-2.12 Naming irregular dendrimers with a symmetrical core unit

DH-2.12.1 Irregular dendrimers are named by dendrimer substitutive nomenclature, as the dendron-substituted parent hydride of the innermost core component (DH-2.8, DH-2.10.2).

DH-2.12.2 Dendrons and substituents are cited in alphabetical order (cf. DH-2.10.2 above and P-14.5 [15]). If dendrons differ only by the number of generations, the smallest is cited first.

Example 11. Irregular dendrimer with a symmetrical core unit (Fig. 18).

Fig. 18:

Example of an irregular dendrimer with a symmetrical core unit.

This irregular dendrimer is composed of two parts: on the left side, a hydro-terminated dendron with ethylenenitrilo CRUs (branch points last in the dendron direction) and a nitrilo simple core unit (G=4). On the right side, two identical dendrons are attached to the nitrilo core. They are formed of propane-1,3-diylnitrilo CRUs (branch points last in the dendron direction) and of 2-cyanoethyl end-groups (G=3). Dendrimer substitutive nomenclature must be used:

[ω-hexadecahydro-dendro^G4-(ethylenenitrilo)-α-yl]bis[ω-octakis(2-cyanoethyl)-dendro^G3- (propane-1,3-diylnitrilo)-α-yl]azane

Since “hexa” alphabetizes earlier than “octakis”, the 2-cyanoethyl-terminated dendron is cited last (DH-2.12.2).

Example 12. Irregular poly(benzyl ether)-type dendrimer with a symmetrical core unit (Fig. 19).

Fig. 19:

Irregular poly(benzyl ether)-type dendrimer with a symmetrical core unit described in ref. [30].

This irregular dendrimer is composed of two parts: the left part consists of a (4-cyanobenzyl)oxy-terminated dendron with an oxymethylenebenzene-1,3,5-triyl CRU (branch point last) and G=4. The right one consists of a hydro-terminated dendron with the same oxymethylenebenzene-1,3,5-triyl CRU and G=6. The core unit is a biphenyl moiety, where, according to organic-chemical nomenclature rules, the two phenyl-connecting carbon atoms must be numbered 1,1′ (fixed numbering).

Dendrimer substitutive nomenclature must be used:

4-{ω-hexadecakis[(4-cyanophenyl)methoxy]-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl}- 4′-[ω-tetrahexacontahydro-dendro^G6-(oxymethylenebenzene-1,3,5-triyl)-α-yl]-1,1′-biphenyl

Since “hexa” alphabetizes earlier than “tetra”, the (4-cyanophenyl)methoxy-terminated dendron is cited first (DH-2.12.2).

Example 13. Irregular poly(benzyl ether)-type dendrimer (Fig. 20).

Fig. 20:

Irregular poly(benzyl ether)-type dendrimer described in ref. [24].

This irregular dendrimer is composed of two (4-bromobenzyl)oxy-terminated dendrons (G=3) and one hydro-terminated dendron (G=4) (see Example 3). Dendrimer substitutive nomenclature must be used:

1-{4-[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}-1,1-bis- (4-{ω-octakis[(4-bromophenyl)methoxy]-dendro^G3-(oxymethylenebenzene-1,3,5-triyl)-α-yl}phenyl)ethane

Bromo-terminated dendrons are cited last, since “hexa” alphabetizes earlier than “octakis” (DH-2.12.2).

DH-2.13 Naming irregular dendrimers with an unsymmetrical core unit

An irregular dendrimer with an unsymmetrical core unit is named by substitutive nomenclature as being the dendron-substituted parent hydride of the innermost core component, according to organic-chemical nomenclature rules [15].

Example 14. Irregular dendrimer with an unsymmetrical core unit (Fig. 21).

Fig. 21:

Example of an irregular dendrimer with an unsymmetrical core unit.

This irregular dendrimer is based on the unsymmetrical core unit of Example 10 (Fig. 17). Dendrimer substitutive nomenclature must be used. The 1,2,5 (lowest possible) locant set is chosen for the innermost component. Dendron and phenyl substituents are cited in alphabetical order. Multiplicative prefixes belong to the dendron names and are hence taken into account (DH-2.12.2): “bis…hexa” alphabetizes earlier than “bis…octa”.

5-{3,5-bis[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl]phenyl}- 1-[4-({bis[ω-octahydro-dendro^G3-(ethylenenitrilo)-α-yl]amino}methyl)phenyl]-2-phenylpentane

DH-2.14 Naming dendritic block polymers

Dendritic block-copolymers are named as dendron-substituted polymers, according to polymer nomenclature rules. The multiplicative nomenclature may, however, be used in the specific case of uniform polymers of exactly known chain length.

Example 15. Dendron-substituted poly(oxyethylene) (Fig. 22).

Fig. 22:

Example of a dendron-substituted poly(oxyethylene).

Depending on the position of poly(oxyethylene) brackets, this dendritic block copolymer can be regarded as either:

1. A poly(oxyethylene) with a dendron-substituted methyl end-group at one end and a methoxy end-group at the other (structure shown above),

2. A poly(oxyethylene) with a dendron-substituted methoxy end-group at one end and a methyl end-group at the other.

The α-end (i.e. the senior end) of a polyoxyethylene chain is at the senior subunit of its last CRU, i.e. oxy. Therefore, the α-end can only be a methyl or a substituted methyl group and is cited first, leading to:

α-({ω-hexadecakis(hydroxymethyl)-dendro^G4-[methyleneoxy- (2-methyl-1-oxoethane-1,2,2-triyl)]-α-yl}methyl)-ω-methoxypoly(oxyethylene)

or:

α-methyl-ω-({ω-hexadecakis(hydroxymethyl)-dendro^G4-[methyleneoxy- (2-methyl-1-oxoethane-1,2,2-triyl]-α-yl}methoxy)poly(oxyethylene)

Since “hexadecakis” alphabetizes earlier than “methoxy”, the first name is correct (structure shown above).

Example 16. Dendron-substituted poly(oxyethylene) (Fig. 23).

Fig. 23:

Dendron-substituted poly(oxyethylene) described in ref. [31].

In this example, the chain linking the two 5-generation dendrons is formed of exactly one ethylene unit and 23 oxyethylene units and can be named oxybis[undeca(ethyleneoxy)ethylene] according to multiplicative nomenclature rules. The molecule can be regarded as a dendrimer molecule and named according to dendrimer multiplicative nomenclature rules:

α,α′-{oxybis[undeca(ethyleneoxy)ethylene]}bis[ω-dotriacontahydro-dendro^G5- (oxymethylenebenzene-1,3,5-triyl)]

The substitutive name is derived from polymer nomenclature, with dendrons as end-groups. The dendron-substituted ethyl group is substituent to the α-end (oxy) of the oxyethylene chain:

α-{2-[ω-dotriacontahydro-dendro^G5-(oxymethylenebenzene-1,3,5-triyl)-α-yl]ethyl}- ω-[ω-dotriacontahydro-dendro^G5-(oxymethylenebenzene-1,3,5-triyl)-α-yl]tricosa(oxyethylene).

If the central poly(oxyethylene) chain were non-uniform, the multiplicative nomenclature could no longer be applied. The substitutive name of the dendritic block-copolymer would be:

α-{2-[ω-dotriacontahydro-dendro^G5-(oxymethylenebenzene-1,3,5-triyl)-α-yl]ethyl}- ω-[ω-dotriacontahydro-dendro^G5-(oxymethylenebenzene-1,3,5-triyl)-α-yl]poly(oxyethylene)

DH-2.15 Naming dendritic graft polymers

In a dendritic graft polymer, the chain is considered to be composed of dendron-substituted constitutional repeating units and named according to the rules established for regular or irregular single-strand copolymers [12]:

poly(CRU1); poly[(CRU1)/(CRU2)]; poly[(CRU1)/(CRU2)/(CRU3)]; etc.,

where one or more types of CRUs are dendron-substituted.

Example 17. Dendritic graft poly(1,4-phenyleneethyne-1,2-diyl) (Fig. 24).

Fig. 24:

Dendritic graft poly(1,4-phenyleneethyne-1,2-diyl) described in ref. [32].

This regular polymer is named as usual [9, 12], with dendrons as pendant groups.

poly({2,5-bis[ω-octamethoxy-dendro^G3-(oxymethylenebenzene-1,3,5-triyl)-α-yl]- 1,4-phenylene}ethyne-1,2-diyl-1,4-phenyleneethyne-1,2-diyl)

Example 18. Dendritic graft polystyrene copolymer (Fig. 25).

Fig. 25:

Dendritic graft polystyrene copolymer described in ref. [31].

poly{[1-(4-{[ω-hexadecahydro-dendro^G4-(oxymethylenebenzene-1,3,5-triyl)-α-yl]methyl}- phenyl)ethylene]/(1-phenylethylene)}

DH-3.1 Choice and name of the preferred constitutional repeating unit

The preferred constitutional repeating unit is chosen and named according to the rules defined for dendrimers (DH-2.2 and DH-2.5)

DH-3.2 Choice and name of the preferred core unit

The preferred core-unit is chosen according to the rules defined for dendrimers (DH-2.4). It is named substitutively, according to the nomenclature of organic chemistry [15], and is regarded as the α-end of the polymer chain.

1. See also DH-2.7.

DH-3.3 Naming the end-groups

The preferred end-groups are chosen according to the rules defined for dendrimers (DH-2.3). They are named substitutively, according to the nomenclature of organic chemistry [15], and are considered to be ω-ends of the polymer chain. See also DH-2.6.

1. The number of end-groups cannot be specified in hyperbranched polymer names.

DH-3.4 Naming hyperbranched polymers and oligomers

A hyperbranched oligomer or polymer is named by citing in order the name of the core unit preceded by α-, the name(s) of the end-groups(s) preceded by ω- and, after the italicized prefix -hyper- and prefix poly, the parenthesized name(s) of the preferred constitutional repeating unit(s) of lower connectivity followed by the preferred constitutional repeating unit(s) of higher connectivity, if any. When the CRU contains more than one type of component of connectivity larger than 2, the component of highest connectivity should be cited last. If a further choice is needed, the component of highest seniority should be cited last.

1. The prefix -hyper- preceding the prefix ‘poly’ indicates the hyperbranched nature of the polymer, i.e. the presence of an unspecified number of linear or semi-dendritic CRUs in the polymer chain.

2. When the polymer contains more than one type of CRU and/or blocks or grafts, the rules of polymer nomenclature [12], [13], [33] should be followed.

3. Whether the compound is to be considered oligomeric or polymeric can be specified by the prefix ‘oligo’ or ‘poly’ preceding the parenthesized name of the preferred CRU.

Generic formats of the names are:

α-(core unit name)-ω-(end-group1 name)-ω-(end-group2 name)-…-hyper-poly(CRU)

α-(core unit name)-ω-(end-group1 name)-ω-(end-group2 name)-…-hyper-oligo(CRU)

α-(core unit name)-ω-(end-group1 name)-ω-(end-group2 name)-…-hyper-poly[(CRU1)/(CRU2)]

α-(core unit name)-ω-(end-group1 name)-ω-(end-group2 name)-…-hyper-oligo[(CRU1)/(CRU2)]

Example 19. Hyperbranched polymer with (dimethylsilyl)oxy end-groups and a (prop-2-en-1-yl)silanetriyl core (Fig. 26).

Fig. 26:

Typical molecule of the hyperbranched polymer with (dimethylsilyl)oxy end-groups and a (prop-2-en-1-yl)silanetriyl core described in ref. [34].

α-[(prop-2-en-1-yl)silanetriyl]-ω-[(dimethylsilyl)oxy]-hyper- poly[oxy(dimethylsilanediyl)propane-1,3-diylsilanetetrayl]

Source-based name: poly{3-[(dimethylsilyl)oxy]-1,1,5,5-tetramethyl-3-(prop-2-en-1-yl)trisiloxane}

Example 20. Hyperbranched polylysine with amino end-groups and a methoxycarbonyl-substituted pentane core unit (Fig. 27).

Fig. 27:

Typical molecule of the hyperbranched polylysine with amino end-groups and a methoxycarbonyl-substituted pentane core unit described in ref. [35].

The CRU is azanediyl(1-oxohexane-1,2,6-triyl). Locants 1,2,6 are cited in the dendron direction.

α-[1-(methoxycarbonyl)pentane-1,5-diyl]-ω-amino-hyper-poly[azanediyl(1-oxohexane-1,2,6-triyl)]

Source-based name: polylysine

Example 21. Hyperbranched polyester obtained from 3-hydroxy-2-(hydroxymethyl)-2-methylpropanoic acid and 2-ethyl-2-(hydroxymethyl)propane-1,3-diol (Fig. 28).

Fig. 28:

Typical molecule of the hyperbranched polyester obtained from 3-hydroxy-2-(hydroxymethyl)-2-methylpropanoic acid and 2-ethyl-2-(hydroxymethyl)propane-1,3-diol described in ref. [8].

α-(propane-1,1,1-triyl)-ω-(hydroxymethyl)-hyper-poly[methyleneoxy(2-methyl-1-oxoethane-1,2,2-triyl)]

Source-based name:

α-(propane-1,1,1-triyl)-ω-(hydroxymethyl)poly[3-hydroxy-2-(hydroxymethyl)-2-methylpropanoic acid]

1. This polymer is synthesized from 3-hydroxy-2-(hydroxymethyl)-2-methylpropanoic acid and 2-ethyl-2-(hydroxymethyl)propane-1,3-diol. The source-based name should specify the nature of the core unit (‘α-’ end-group) and of the end-groups (‘ω-’ end-groups).

Example 22. hyperbranched polyester obtained from 3-hydroxy-2-(hydroxymethyl)-2-methylpropanoic acid (Fig. 29)

Fig. 29:

Typical molecule of the hyperbranched polyester obtained from 3-hydroxy-2-(hydroxymethyl)-2-methylpropanoic acid described in ref. [8].

α-(1-carboxyethane-1,1-diyl)-ω-(hydroxymethyl)-hyper- poly[methyleneoxy(2-methyl-1-oxoethane-1,2,2-triyl)]

Source-based name: poly[3-hydroxy-2-(hydroxymethyl)-2-methylpropanoic acid]

Example 23. Hyperbranched polymer prepared by the ring-opening polymerization of 3-(7-oxoazepan-4-yl)-propanoic acid (Fig. 30).

Fig. 30:

Hyperbranched polymer from 3-(7-oxoazepan-4-yl)propanoic acid decribed in ref. [36]

The preferred CRU is (3-oxopropane-1,3-diyl)azanediylpropane-1,3,3-triyl (branch points last). In the CRU name, locants are assigned and cited in the dendron direction.

α-(7-oxoazepan-4-yl)-ω-(2-carboxyethyl)-hyper-poly[(3-oxopropane-1,3-diyl)- azanediylpropane-1,3,3-triyl]

Source-based polymer name: poly[3-(7-oxoazepan-4-yl)propanoic acid]

Example 24. Hyperbranched polyester prepared from propane-1,2,3-triol and benzene-1,2,4-tricarboxylic acid (Fig. 31).

Fig. 31:

Example of hyperbranched polyester prepared from propane-1,2,3-triol and benzene-1,2,4-tricarboxylic acid.

There are two types of end-groups, hydroxy and carboxy groups and no specified core unit. The structure is ill-defined and, furthermore, depends on reaction conversion and on the initial stoichiometric ratio of reactants. Structure-based nomenclature cannot be applied.

For polyesters obtained by two-monomer polycondensation, the source-based nomenclature for single-strand polymers is used [12], [33]. SB-2.3 recommends the use of the functional class name of the corresponding apparent cyclic monomer (SB-1.1 [33]), e.g. poly(ethylene terephthalate) [33]. This nomenclature may be extended to trifunctional monomers:

poly(propane-1,2,3-triyl benzene-1,2,4-tricarboxylate)

However, as stated above, such an apparent monomer is difficult to found for this polymer, the structure of which is highly dependent on the exact reaction conditions. So, a name based on the real monomers is more convenient:

poly(benzene-1,2,4-tricarboxylic acid-co-glycerol) or

poly(benzene-1,2,4-tricarboxylic acid-co-propane-1,2,3-triol)