On the Stille vinylation reactions with alpha-styryltrimethyltin

Stille vinylation reactions involving alpha-styryltrimethyltin 3b and a series of chloro- or bromo-pyridine derivatives are described. In contrast to the rare cine seletivity observed with iodobenzene 10a or 3-iodotoluene 10b, reactions between vinyltin 3b and a series of 2-halopyridine derivatives 25(a-d) yield 1,1-disubstituted ipso-coupled olefins 16(a-d) as the predominant products. (C) 1997 Elsevier Science Ltd.