Reaction of 3-trimethylsilyloxy-2-aza-1,3-dienes with zirconocene: a transition metal promoted retro-Brook rearrangement

2-Aza-1,3-dienes bearing trimethylsilyloxy group at C3 undergo an unusual zirconium-mediated retro-Brook rearrangement to produce, after hydrolysis, silylated amides. Both [1,3]- and [1,4]-oxygen to carbon silyl migrations are observed depending on the substrate structure.