General Synthesis of ω-Acetylenic Vinyl Esters and Ethers

Article abstract of DOI:10.1021/jo00339a021

Vinyl ethers of the general structure CH2=CHO(CH2)nCCH and vinyl esters of the general structure CH2=CHOC(O)(CH2)nCCH have been prepared by mild elimination methods from the corresponding ω-acetylenic alcohols and acids.A two-step procedure involving addition of alcohol to (trimethylsilyl)oxirane followed by silanol elimination, and only slightly modified from the one developed by Hudrlik, provides the vinyl ethers in average overall yields of 45percent.The vinyl esters must be prepared in three steps due to the unexpected lack of reactivity of the acid-oxirane adducts toward elimination.Vinyl 3-butynoate is not accessible at all via this route.Other vinyl esters are realized in overall yields of 40percent or better.Several of these compounds exhibit high reactivity toward Co2(CO)8 in preliminary studies of possible cyclization reactions.