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organic halides or pseudo halides [6]. The Suzuki reaction has recently gained much prominence because it is suitable for large-scale synthesis including the industrial synthesis of pharmaceuticals and fine chemicals [7–9]. The key advantages of Suzuki coupling are mild reaction conditions and commercial availability of a wide variety of heterocyclic and arylboronic acids that are safer than other organometallic reagents [10–14]. The Suzuki coupling process tolerates many functional groups present in substrates [15], and it proceeds well in the presence of water. In

, 13C NMR Spectra, UV Spectra, 'H NMR Spectra 9,9'-Oxy-bis(acridinium) salts 2a and 2b as well as the 9,9'-thio-bis(acridinium) salt 2c have been compared with other 9-substituted acridinium salts by NMR, 13C NMR, and UV/VIS spectra. The data show that the bond state of the acridine rings in 2a—c is quite similar to that in 9-(pseudo)halide-substituted acridinium ions, i.e., the aromatic conjugation throughout the heterocyclic system is not disturbed. Dikationether ( l a ) verhalten sich bezüglich ihrer chemischen Reaktivität in vielerlei Hinsicht ähnlich

pseudohalides in the presence of catalytic amounts of the crown ether 18-crown-6 to give the tri-£er£-butylsilicon pseudo- halides (*-C4H9)3SiX (X = CN, NCO, NCS, N3) in good yields. These new compounds are characterized by IR, *H NMR, and mass spectra. In the absence of the crown ether no reaction occurs. Treating tri-£er£-butylsilane with AgX (X = CN, SCN) gives the silicon pseudohalides in low yields. Obgleich Organosiliciumpseudohalogenide schon eine Reihe von Jahren bekannt sind [2], besitzt diese Stoff klasse auch weiterhin ein aktuelles Inter- esse bezüglich der

-Trifloxyacridinium salts 3a, b and 9,9'-oxy-bis(acridinium) salts 4a, b which are easily ob­ tained from the 9-acridones 2 a, b react readily with halides, pseudohalides and sulfur nucleophiles to give 9-substituted acridinium ions. This reaction represents an efficient alternative to the commonly used transformation of 9-chloroacridinium into other substituted acridinium salts; the two-step conversion of the carbonyl com pound into a (pseudo)halide-substituted carbenium ion or into a thione may be generally applicable to ketones which can be transformed either into trifloxy

(RCL) of aqueous dye (DH) solutions, [DH + -OH] + ea q - -> DH* + OH - . The results abundantly confirm other published data. RCL changes upon addition of phosphates indicate prototropic reactions with the oxidized dye, D ' - f ^ P O ^ ^ DH- + + HPO4 2 - , promoting or inhibiting the formation of semioxidized dye (DH-+) as the most efficient RCL precursor. The RCL enhancement commonly observed upon addition of halides and pseudo halides is discussed at some length on the base of previous and present results in order to focus attention to the possible

cornpounds (as these can be used for continuous cyclic processes). The outstanding phenomenon as regards the preparation of organosilicon halides in molten salts as reaction media is the fact that neither solvolysis with the reactants must be feared, nor are complicated operations required to separate the reaction products from the solvent. 93 W. SUNDERMEYER APPLICA TIONS OF FUSED SAL TS By using pseudo-halogen in place of halogen in molten alkali pseudo- halides we found2 an interesting way for the preparation of cyanides, iso- cyanates, and isothiocyanates of

: dlibasse(a),gmail. com ABSTRACT Ten organotin selenito compounds obtained on allowing Se03(SnPh3)2 to react with triphenylphosphine oxyde, urea and tetraphenylphosphonium- tetramethylammonium- acetonyltriphenylphosphonium- and tetraethylammonium halides or pseudo halides have been studied by infrared and Mössbauer spectroscopies, then discrete and infinite chains structures suggested on the basis of spectroscopic data. Key words: selenite anion, IR and Mossbauer, infinite chain and discrete structures INTRODUCTION The chemistry of organotin (IV) compounds

various hypervalent di- and triorganotin complexes. Extensive examples of di- and triorganotin complexes have been reported III 263 Vol. 29, No. 5, 2006 Crystal Structure of Dicyclohexylammonium thiolactato Triphenyl Sstannate in the literature, as well as their biological activities 111. One problem that may limit their biological activities is their low solubility. Ionic complexes may eliminate the solubility question due to their partially ionic characteristics. Di- and trimethyltin halides or pseudo-halides /3-5/ are typical examples of five- and six

,1 -bis(dimethy lthiourea)digold(T). Acta Ciys- tallogr. C56 (2000) 798-800. 5. Friedrichs, S.; Jones, P. G.: Bis(imidazolidine-2-thione)gold(I) diiodo- aurateO). Acta CrystaUogr. CSS (1999) 1625-1627. 6. Popovic, Z.; Matkovic-Calogovic, D.; Pavlovic, G.; Soldin, Z.; Giester, G.; Rajic, M.; Vikic-Topic, D.: Preparation, thermal analysis and spectral characterization of the 1:1 complexes of mercury(H) halides and pseudo- halides with 3,4,5,6-tetrahydropyrimidine-2-thione. Crystal structures of bis(3,4,5,6-tetrahydropyrimidine-2-thione-S)mercury(II) tetrachloro- and