Catalytic Addition of Alkyne C-H,Amine N-H,and Phosphine P-H Bonds to Carbodiimides:An Efficient Route to Propiolamidines, Guanidines, and Phosphaguanidines

摘要

1.Introduction Multi-substituted amidines, guanidines, and phosphaguanidines of a general formula R'N=C(ER)NHR'(E=CR1R2,NR1,PR1) are an important family of heteroatom-containing organic compounds,which can serve as building blocks for many biologically relevant compounds and as stabilization iigands for various metal complexes,1 Several routes are known for the synthesis of these compounds,but most of them are based on stoichiometrie reactions.In contrast,catalytic approaches to these compounds are much less extensively studied.