Dithio and thiono esters, LIV: Attempted synthesis of α-amino dithio esters by the bislactim ether method

Article abstract of DOI:10.1002/ardp.19933260202

Sulfhydrolysis of 2,5-bis(methylthio)-3,6-dihydropyrazine (5) gives rise to 2,5-piperazinedithione (8) and not to glycine dithiomethylester (6). The iminium salts 9, obtained by alkylation of 5, add H₂S to form the 1,4-dialkyl 2,5-piperazinedithiones 10. 5 reacts with methyl chloroformate to give 2,5-bis(methylthio)-pyrazine (11), and with acetic anhydride to give the 1,4-dihydropyrazine 12. Sulfhydrolysis of the 6-membered and 7-membered iminium salts 14 leads to the thiolactames 15.