Tandem Rh(II)-catalyzed 1,3-acyloxy migration/intermolecular [2+2] cycloaddition of electronically deficient propargylic esters with alkenes and alkynes

Transition metal-catalyzed 1,3-acyloxy migration of propargylic esters represents one of the most straightforward routes to access allene intermediates, which could engage in various fascinating subsequent transformations. However, this process is...