Collect. Czech. Chem. Commun.
1987, 52, 995-1005
https://doi.org/10.1135/cccc19870995
Selectivity of nucleophilic addition to and substitution at isothiocyanatocarbonyl group. Reactions of 4-pentinoyl- and 2-(2-propinyl)-4-pentinoyl isothiocyanate with amines and methanol
Peter Kutschy, Pavol Kristian, Milan Dzurilla, Dušan Koščík and Róbert Nádaskay
Department of Organic Chemistry and Biochemistry, P. J. Šafárik University, 041 67 Košice
Abstract
4-Pentinoyl isothiocyanate reacts with primary and secondary amines by either nucleophilic addition to N=C=S group to yield the corresponding thioureas, or a nucleophilic substitution at the carbonyl group to give 4-pentinoic acid amides. The less nucleophilic diphenylamine reacts selectively to afford the product of nucleophilic addition only. 2-(2-Propinyl)-4-pentinoyl isothiocyanate, having a sterically hindered carbonyl group, furnished with primary amines a mixture of amides and thioureas, whereas the bulkier secondary amines react selectively to form thioureas only. Both isothiocyanates afford with methanol as a nucleophile exclusively the corresponding O-methyl monothiocarbamates.
