A more sustainable isothiocyanate synthesis by amine catalyzed sulfurization of isocyanides with elemental sulfur.

ABSTRACT: Isothiocyanates (ITCs) are typically prepared using amines and highly toxic reagents such as thiophosgene, its derivatives, or CS₂. In this work, an investigation of a multicomponent reaction (MCR) using isocyanides, elemental sulfur and amines revealed that isocyanides can be converted to isothiocyanates using sulfur and catalytic amounts of amine bases, especially DBU (down to 2 mol%). This new catalytic reaction was optimized in terms of sustainability, especially considering benign solvents such as Cyrene™ or γ-butyrolactone (GBL) under moderate heating (40 °C). Purification by column chromatography was further optimized to generate less waste by maintaining high purity of the product. Thus, E-factors as low as 0.989 were achieved and the versatility of this straightf

SUBMITTER: Nickisch R 

PROVIDER: S-EPMC8693870 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature