Zirconium-induced cyclizations of long-chain α,ω-Diyne derivatives - The surprising one-pot formation of dimeric structures

摘要

Dimeric products were produced besides the monomeric (and expected) cyclization product, on subjecting diacetylenes to the conditions developed by Negishi (ZrCp_2 from ZrCp_2Cl_2 and -BuLi). The structures of the dimeric products were established by spectroscopic data and single-crystal X-ray structural analysis. The mechanisms leading to their formation are discussed.