Categories: Synthesis of N-Heterocycles, Synthesis of S-Heterocycles >

Synthesis of thiazole-2-thiones

Multicomponent reactions of CS₂, sulfoxonium ylides and secondary amines provide β-keto dithiocarbamates, whereas primary amines afforded thiazolidine-2-thiones or thiazole-2-thiones after dehydration in an acidic environment. These simple, versatile, and catalyst-free synthetic methods have a wide substrate scope and excellent functional group tolerance.
N. Kumar, A. Sharma, U. Kumar, S. K. Panday, J. Org. Chem., 2023, 88, 6120-6125.

A convenient base-catalyzed three-component reaction between chalcones, isothiocyanates, and elemental sulfur provides thiazole-2-thiones in very good yields.
T. B. Nguyen, P. Retailleau, Org. Lett., 2021, 23, 5344-5348.

An oxidative cascade cyclization strategy enables an unprecedented construction of thiazole-2-thiones from enaminones via a cascade of C(sp²)-H/C(sp²)-H bond sulfurations and C(sp³)-H bond thiocarbonylation. This transformation allows for the efficient synthesis of thiazole-2-thiones with broad tolerance in moderate to excellent yields from simple enaminones with elemental sulfur.
B. Zhan, D. Liu, Y. Sun, Y. Zhang, J. Feng, F. Yu, Org. Lett., 2021, 23, 3076-3082.