Unusual Cleavage of the Enolsilane C-O Bond: Transformation of 2-Silyloxy-1,3-dienes into 1,3-Dienyl-2-zirconium Compounds and their Cross-Coupling Reactions
31 December 2001 (online)
Aryl enolsilanes and 2-silyloxy-1,3-dienes react with zirconocene to give alkenylzirconium, and novel 1-methylene-2-propenylzirconium compounds which can be used as 2-dienylation reagents. Thus, one-pot coupling of 4-phenyl-1,3-butadienyl-2-zirconocene (2d) with a range of electrophiles including aryl, alkynyl, allyl halides, bromine, iodine and a Michael acceptor occurs regioselectively at the C-2 position in the presence of Pd or Cu catalysts.
silyloxydienes - zirconium - dienylzirconocenes - cross-coupling