2,2,4,4,6,6-Hexabenzylcyclotristannatellurane, (Bn 2 SnTe) 3 . Synthesis and Structural Characterization of an Organometallic Single-Source Precursor to Phase-Pure, Polycrystalline SnTe Philip Boudjouk,* Michael P. Remington, Jr., Dean G. Grier, Wayne Triebold, and Bryan R. Jarabek Center for Main Group Chemistry, Department of Chemistry, North Dakota State University, Fargo, North Dakota 58105 Received July 1, 1999 The title compound, (Bn 2 SnTe) 3 , Bn ) CH 2 C 6 H 5 , was prepared in high yield by treating Bn 2 SnCl 2 with (NH 4 ) 2 Te. Details of the synthesis and characterization ( 1 H, 13 C, 119 Sn, and 125 Te NMR; IR, single-crystal XRD, and elemental analyses) are presented. (Bn 2 SnTe) 3 serves as an efficient single-source precursor to phase-pure cubic SnTe under mild conditions Introduction Tin telluride and other tin chalcogenides are widely used as semiconductors. 1 For example, SnTe, with a direct E g of 0.18 eV, 2 has found application in infrared detection, radiation receiving, and thermoelectric de- vices. 3 Interest in the structure and bonding of 14-16 materials has also driven research in this area. 4 Syn- thetic routes to these materials include heating mix- tures of the elements at high temperatures for extended time periods, 5 reaction of the elements in liquid am- monia, 6 precipitation from aqueous solutions, 7 organo- metallic chemical vapor deposition (OMCVD), 8 solid- state metathesis, 9 and, more recently, pyrolysis of organometallic single-source precursors. 10 We have demonstrated that ring systems of the type (Bn 2 SnE) 3 , (Bn ) CH 2 C 6 H 5 ,E ) S or Se) provide the 14-16 material in high yields and high purity by homolytic bond cleavage of the C-Sn bond. 10a This route has the advantages of utilizing mild decomposition temperatures, producing an inert and easily removed organic byproduct, 1,2-diphenylethane, and controlling the stoichiometry of the end members as well as the corresponding solid solutions, SnS x Se 1-x . Easy access to solid solutions allows tailoring of the band gap. 11 Furthering our investigation of molecular precursors to 14-16 materials, we report here the synthesis, char- acterization, and decomposition of the novel six-mem- bered ring containing alternating Sn and Te atoms, (Bn 2 SnTe) 3 . This compound serves as an organometallic single-source precursor to cubic SnTe under mild ther- mal conditions (g200 °C). Homolytic bond cleavage of the Sn-C bond and the formation of 1,2-diphenylethane is the dominant mechanism. Results and Discussion Precursor Synthesis. Cyclic tin chalcogenides can be prepared by the reaction of a dialkyldihalostannane, R 2 SnX 2 , with alkali metal chalcogenolates, MEH, 12 or by treating elemental chalcogens with dialkylstan- nanes. 13 Recently we reported that these compounds are accessible in good to excellent yields from R 2 SnX 2 and freshly prepared anhydrous alkali metal chalcogenides, M 2 E 10a,c (eq 1). 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