Recently, phosphine-catalyzed [3+ 2] cycloadditions of allenoates with electron-deficient olefins and imines—a process which provides efficient access to a variety of synthetically useful carbo-and heterocycles from readily available starting materials—have received considerable research interest [1, 2] since the pioneering works of Lu and co-workers.[1j] As a result of continuing efforts from many research groups in this field, an array of new ...
