161692-52-0Relevant academic research and scientific papers
-VERSUS -SIGMATROPIC REARRANGEMENT OF O-SUBSTITUTED ALLYL N-ACYLMONOTHIOCARBAMATES
Ficeri, Vlastimir,Kutschy, Peter,Dzurilla, Milan,Imrich, Jan
, p. 2650 - 2662 (1994)
Substituted allylic alcohols (2-buten-1-ol, 1-buten-3-ol, cinnamyl alcohol and 3-methyl-2-buten-1-ol) react with acyl isothiocyanates (4-chlorobenzoyl, 2,6-difluorobenzoyl, 3-phenylpropenoyl, 2-thienocarbonyl, 3-chloro-2-thienocarbonyl and 3-chloro-2-benzothienocarbonyl isothiocyanate) with the formation of highly reactive O-substituted allyl N-acylmonothiocarbamates, which either spontaneously or by heating in boiling benzene undergo -sigmatropic rearrangement to S-substituted allyl N-acylmonothiocarbamates.The structure of S-series with isomerized allylic group affords the unequivocal evidence of the -sigmatropic route of studied rearrangement.Further heating of -rearranged N-(4-chlorobenzoyl)monothiocarbamates results in the -sigmatropic shift of monothiocarbamate group.Using arylalkyl alcohols with the allylic double bond inserted into an aromatic system the obtained O-esters either do not undergo any rearrangement (benzyl alcohol) or undergo -sigmatropic rearrangement (2- and 3-furylmethanol and 1-(2-furyl)ethanol) to the corresponding S-esters.For explanation of this reaction the tandem of - and -sigmatropic rearrangements is suggested.
