Dehydrogenative Dimerization of Di-tert-butyltin Dihydride Photochemically and Thermally Catalyzed by Iron and Molybdenum Complexes

✍ Scribed by Hemant K. Sharma; Renzo Arias-Ugarte; Alejandro J. Metta-Magana; Keith H. Pannell

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 350 KB
• Volume: 48
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.200902327

✦ Synopsis

Dehydrogenative coupling of tertiary stannanes, R 3 SnH, catalyzed by a transition metal is known to produce distannanes, R 3 SnÀSnR 3 , [1] whereas a mixture of cyclic and linear oligo-or polystannanes is obtained from the analogous dehydrogenative coupling of secondary stannanes, R 2 SnH 2 . [2][3][4] 1,2-Dihydrodistannanes are of significant interest as bifunctional model compounds to mimic the properties of polystannanes and they are excellent precursors for further derivatization. However, until a report by Uhlig et al. [5a] there were no well-defined methodologies for the synthesis of 1,2dihydrodistannanes. [6] The Uhlig synthesis involves a two-step reaction sequence that starts with the reaction of tertbutylmagnesium chloride with tin tetrachloride in an overall yield of 2.5 %. We now report the photochemical and thermal dehydrogenative dimerization of tBu 2 SnH 2 (1) to tBu 2 HSnÀ SnHtBu 2 (2), catalyzed by the iron catalysts 3 and 4 and their molybdenum analogues 5 and 6. ½ðh 5 -C 5 H 5 ÞFeðCOÞ 2 Me ð3Þ ½ðh 5 -C 5 H 5 ÞFeðCOÞðPPh 3 ÞMe ð4Þ ½ðh 5 -C 5 H 5 ÞMoðCOÞ 2 ðLÞMe; L ¼ CO ð5Þ, PPh 3 ð6Þ [**] This work was supported by Welch Foundation, Houston, TX (Grant AH-546) and the NIH-MARC U-STAR program.