Highly efficient synthesis of cis-[3]cumulenic diols via zirconocene-mediated coupling of 1,3-butadiynes with aldehydes
A highly efficient and convenient method for the monozirconation of silyl- or tert-butyl-substituted 1,3-butadiynes using the Negishi reagent has been developed. The resulting zirconium butadiyne complexes undergo two syn-SE2 reactions with various aldehydes to yield the cis-[3]cumulenic diols with moderate to high diastereoselectivities. The silyl substituents at the butadiyne terminus show remarkable influence on the diastereoselectivity.