Chemical fixation of CO2/CS2 to access iodoallenyl oxazolidinones and allenyl thiazolidine-thiones

Abstract

Constructing heterocyclic compounds by chemical fixation of CO₂/CS₂ as a C1 building block is a promising approach. An efficient and environmentally friendly synthetic approach has been developed using CO₂/CS₂ to prepare complicated allenyl heterocycles with high yields and diastereoselectivities in a metal-free manner under mild conditions. NIS promoted CO₂ fixation and the cyclization reaction by exclusive 1,4-syn-addition of 1,3-enynes rather than 1,2-addition or 3,4-addition, while CS₂ participated in unique 1,4-syn-hydrothiolation of 1,3-enynes to afford allenyl heterocycles with different reaction patterns.