摘要:
Reactions of allyl and 2-(vinyloxy)ethyl isothiocyanates with alyylmagnesium bromide (THF-Et2O, 20-30degreesC, 1-3 h) after hydrolysis or alkylation of adducts afforded respectively N-allyl- and N-[2-(vinyloxy)ethyl]3-butenethioamides or N-allyl- and N-[2-(vinyloxy)ethyl]-1-(methylmercapto)-3-buten-1-imines The reaction carried out in ethyl ether yielded instead of N-allyl-3-butenethioamide its isomer N-allyl-2-butenethioamide that cleanly isomerized in the system KOH-DMSO-H2O into N-(I-propenyl)-2-butenethioamide. N-[2-(vinyloxy)ethyl]-3-butenethioamide suffers a prototropic rearrangement into N-[2-(vinyloxy)ethyl]-2-butenethioamide only in the system t-BuOK-DMSO.