C-C Bond Cleavages of Cyclopropenes: Operating for Selective Ring-Opening Reactions.

This review highlights key reactivities relying on C-C bond cleavages of cyclopropenes. Metal-catalyzed and metal-free transformations are covered in reactions involving direct ring-opening processes or transformations through nonisolable cyclopropane intermediates generated from cyclopropenes. Special emphasis is on the synthetic utility and mechanistic aspects of methodologies discussed along the revision. Different types of reactivities are covered in separate sections including generation of vinyl carbenes and their reactions, metathesis processes, heterocycles syntheses, SEAr reactions, metalation-ring opening sequences, cycloadditions involving ring-cleavages or rearrangements. The focus is on results described from 2007 to the end of 2019, yet relevant pioneering transformations are eventually included.