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  • Author: Armand Blaschette x
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Abstract

Tetramethylsilane reacts with HN(SO2Cl)2 (1) in a complex manner, the nature of the product mixture depending strongly on the reaction conditions. Refluxing 1 with TMS in excess, using CH2Cl2 as a diluent, affords in high yield the new compound HN(SO2Cl)(SO2Me) (2) according to eq. (3). Hydrolysis of the crystal-line, moisture sensitive compound 2 is described by eq. (4).

By reaction with NaN[Si(CH3)3]2, the chlorides C6F5SCl, C6F5S(O)Cl, and C6F5SO2Cl are converted into C6F5SN[Si(CH3)3]2, C6F5S(O)N[Si(CH3)3]2, and Na+[C6F5SO2]-, respectively. In this instance the reactivity pattern of the pentafluorophenyl compounds does not differ from that of similar phenyl derivatives.

Novel organosilicon peroxides, their preparation, properties, and 1H—NMR spectra are discussed.

Abstract

The crystal structure of the title compound was determined at -9 5 °C. It crystallizes in space group P1̄ with a = 577.5(3), b = 820.2(3), c = 1916.6(8) pm, α = 83.34(2), β = 82.83(2), γ = 83.61(2)° and Z = 2. The final R value was 0.034 for 3019 unique observed reflections. The presence of aggregates of four ions (two cations and two an­ ions) in the solid state is observed, with short cat-ion-anion contacts SII ⋯ O (290 pm) and Cl ⋯ O (298 pm). The bond lengths of the 4-dimethylaminopyridinium moiety of the cation suggest a semiquinoid resonance form with a double bond to the nitrogen of the dimethylamino group and two localized double bonds in the ring. The ring, the dimethylamino group (except H atoms) and the Sn atom are coplanar. The SII -N bond length is 170.3 pm, the N -SII -C angle 99.6°. The SII -C bond is approximately perpendicular to the ring plane.

Treating (MeSO2)3N with 4-dimethylaminopyridine in MeCN afforded the ionic title compound (monoclinic, space group P21/c). The bond lengths of the 4-dimethylaminopyridinium moiety suggest a semiquinoid resonance form with a double bond to the exocyclic nitrogen and two localized carbon-carbon double bonds in the ring. The ring and the exocyclic N and S atoms of the cation are essentially coplanar. The S -N bond distances in the cation (173.4 pm) and the anion (159.1 and 159.6 pm) correlate with Pauling bond orders of 1.0 and 1.7, respectively. The anion displays a staggered conformation with approximate C2 symmetry ( S - N -S 120.4°).

Abstract

Di(benzenesulfonyl)amine, 18-Crown-6, Quaternary Complex of Uncharged Molecules, Crystal Structure Co-crystallization of 18-crown-6 (18C6) and di(benzenesulfonyl)amine from dry ethanol at -20 °C affords the thermally labile and structurally uncharacterized ternary complex 18C6·2EtOH·2HN (SO2Ph)2 (2). Single crystals of the quaternary complex 18C6-2 H2O·2EtOH·2HN(SO2Ph)2 (1) were fortuitously obtained by repeated recrystallization of a sample of 2 from ethanol that was not kept completely dry. The crystal packing of 1 (triclinic, space group P1̄) is built up from isolated formula units displaying crystallographic inversion symmetry and pseudo D3d symmetry of the crown ring. The water molecules are located on opposite sides of the ring plane. Each H2O is connected to two OC atoms of the crown separated by a [CH2CH2OCH2CH2] segment (OWH···OC 210 and 208 pm, angles at H 169 and 164°), and accepts an O-H···Ow hydrogen bond from an ethanol molecule (H···OW 176 pm, angle 177°).

Abstract

N-Acyl dimesylamines. like acyl chlorides, react with 4-dimethylaminopyridine and other tertiary nitrogen bases to give either solid N-acylonium dimesylaminides (1-3). or onium dimesylaminides (e.g. 4) originating from ketene elimination (eq. (5)). The expected acyl transfer properties of N-acylonium dimesylaminides are confirmed by reactions of l a with phenol, 4-nitrophenol, p-thiocresol, and N-methylaniline, and of 1b with phenol, resulting in 0-. S-. or N-acylation, respectively. With exception of compounds 1b and 3, all dimesylaminides could be characterized by their cation and anion mass spectra using field desorption, secondary ion mass spectrometry or fast atom bombardment

The ternary complexes 18C6 · 4H2O · 2HN(SO2Ph)2 (3) and 18C6 · 2H2O · 2HN(SO2C6H4⁻4-F)2 (4) were obtained by co-crystallization of 18-crown-6 (18C6) with the appropriate di(arenesulfonyl)amine from aqueous solutions and characterized by low-temperature X-ray diffraction. The crystal structures consist of monomeric formula units displaying crystallographic Ci, symmetry for 3 (monoclinic, space group C2/c) and approximate Ci symmetry for 4 (monoclinic, space group P21/c). In 3, hydrogen-bonded water dimers H2O ··· H - OʹH (H ··· O 182 pm) act as links between the two di(benzenesulfonyl)amine molecules and the crown ring. Each dimer accepts an N - H ··· Oʹ bond (H ··· Oʹ 194 pm) and is attached by its remaining protons to a set of three alternate crown oxygen atoms Oc (OʹH ··· Oc 202, OH ··· Oc 207 and 208 pm). The overall topological features of 3 strongly resemble those of the known supramolecule 18C6 ­· 2MeOH · 2HN(SO2Ph)2. In 4, each amine molecule is N - H ··· O bonded to a water monomer (H ··· O 184 and 187 pm) that is connected to two Oc atoms of the crown (OH ··· Oc 202 - 210 pm). The crown rings of both complexes adopt the frequently observed pseudo D3d symmetry. In the crystal of the pure compound HN(SO2C6H4⁻4-F)2 (5; monoclinic, space group C2/c), the molecules are associated into chains in the z direction through a relatively weak N - H ··· Oʹ bond (H ··· Oʹ 215 pm). The conformations of the HN(SO2R)2 entities in 3, 4, 5 and some related solids are compared and discussed.

The crystal structure of the title compound was determined at —90 °C. It crystallizes in space group PĪ with a = 772.3(2), b = 1071.2(3), c = 1090.4(4) pm, α = 62.65(2), β = 82.71(2), γ = 71.42(2)° and Z = 2. The final R value was 0.031 for 2368 unique observed reflections. The presence of ion pairs in the solid state is observed, with short contacts of 290 pm between the pyridinium nitrogen and an oxygen of the anion. An analysis of the bond lengths suggests that the resonance form with a double bond to the nitrogen of the dimethylamino group and two localized double bonds in the ring, makes a larger contribution to the overall structure than in several similar pyridinium systems; the carbonyl moiety can however be regarded as containing a pure double bond.

High yield syntheses of the new diaminosulfanes (CH3SO2)2NSN (SO2CH3)2 (1) and (CH3SO2 )2 NSSN (SO2CH3)2 (2) are reported. 1 is obtained by the action of elemental sulfur on (CH3S O2)2NCl and by metathesis of (CH3SO2)2N Ag with SCl2, 2 by the analogous metathesis with S2Cl2. 2 is converted to 1 by partial desulfurization with (C6H5)3 P. 1 and 2 are active transfer reagents of the S2⊕ or S5⊕ group, respectively. Thus, the reaction o f 1 or 2 with n -butanol gives the alkoxysulfanes C4H9OSnOC4H9 (n = 1, 2), and their reaction with [(CH3)3Si]2NH leads to the silylated diaminosulfanes [(CH3)3Si]2NSnN[Si(CH3)3]2 (n = 1, 2). The crystal structures of the title com pounds were determined at - 9 5 °C. The most important features of the structure of 1 are the near planarity of the three bonds around the nitrogen atoms (sum of bond angles 356.9 ), the distances N - SII 169.7 and N -SVI 171.5 pm , and the N - SII -N bond angle o f 105.3° (mean values for two independent molecules). In 2, both nitrogen atoms have a planar geometry (sum of bond angles 360.0°; distance from the plane of their bonded atoms ≤ 2 pm). All N - S bond lengths are approximately equal (mean values: N - SII 170.4, N - SVI 170.7 pm). The S - S bond length is 202.1 pm. The torsion angle N - S - S - N of -8 5 ° lies in the usual range for disulfides X - S - S - Y . For comparison, the known structure of CH3 - N (SO2CH3)2 was redetermined at - 9 5 °C.