Tetracyclic silaheterocycle formed through a pericyclic reaction cascade including a two-fold intramolecular C-C bond activation

Helmer J., Pakkanen O.J., Gendy C., Hepp A., Tuononen H.M., Lips F.

Abstract

Reductive debromination of the tribromoamidosilane 2 gave the tetracyclic silaheterocycle 3 through a unique reaction cascade involving unprecedented two-fold intramolecular cycloaddition by transient silylenes. Experimental and computational analyses of the reaction mechanism allowed the identification of the key intermediates that lead to the silaheterocycle 3 or, alternatively, to the cyclotrisilene 19.