Organotin compounds. IX. Reactions between trialkylstannyl-substituted esters and trimethylsilyl halides: exchange vs. hydrolysis

Article abstract of DOI:10.1016/S0022-328X(00)99028-4

A study of the reactions between β- and ω-trialkylstannyl-substituted saturated methylcarboxylates (R=Me, n-Bu, Ph) and trimethylsilyl halides (X=Cl, Br, I) is reported.The results indicate that methyl β-(trialkylstannyl)propanoates react with trimethylsilyl halides to give alkyl/halide exchange products no ester cleavage is observed even using organotin ester/silicon halide ratios of 1/4.The reactions carried out with ω-trialkylstannyl-substituted esters show that the failure of methyl β-(trialkylstannyl)propanoates to give transesterification products is connected with the intramolecular coordination that exists in the methyl β-(halodialkylstannyl)propanoates, alkyl/halide exhange products, which prevents the coordination between the C=O of the ester and the silicon halide.The results obtained also indicate that the alkyl/halide exchange reactions are much faster than the transesterification reactions.Evidence concerning the possibility that these halodealkylation reaction reactions at tin might be a general property of tetralkyltin compounds is presented.