Synthesis and some physical properties of new organometallic compounds containing Si and Sn atoms

This paper reports the synthesis of two new organotin hydrides containing the (phenyldimethylsilyl)methyl ligand. It was found that the reaction of (phenyldime thylsilyl)methylmagnesium bromide in ether afforded ((phenyldimethylsilyl)methyl) trimethyltin (2) (72%), and with (-)-menthyldimethyltin bromide 3 gave (((phenyl dimethylsilyl)methyl)(1R,2R,5R)-2-isopropyl-5-methylcyclohexyl)dimethyltin (4) (84%). Bromodealkylation of 2 with bromine in MeOH led to the corresponding monobromide 5 (82%), which upon reduction with LiAlH₄ yielded ((phenyldimethyl silyl)methyl)methyltin hydride (6) (95%). The best method for obtaining the corresponding bromostannylated derivative of compound 4, i.e., (((phenyldime thylsilyl)methyl)(1R,2R,5R)-2-isopropyl-5-methylcyclohexyl)methyltin bromide (7) was the exchange reaction between 4 an HgBr₂ that led to 7 with 90% yield. The reduction of bromide 7 with LiAlH₄ gave a diastereomers mixture of (((phenyldime thylsilyl)methyl)(1R,2R,5R)-2-isopropyl-5-methylcyclohexyl)methyltin hydride (8). Some physical properties, and ¹H, ¹³C, and ¹¹⁹Sn NMR of the new organotin hydrides as well as that of their intermediate precursors are included.