Reductive cyclisation of Morita–Baylis–Hillman adducts. A simple approach towards substituted hydrindanones and decalones

A connective synthesis of substituted hydrindanones and decalones can be accomplished based upon a novel approach involving two key-steps: a Morita–Baylis–Hillman condensation and an intramolecular reductive cyclisation using lithium in ammonia. Decalones, akin to the middle core of the clerodane family of natural products and bearing a quaternary carbon centre, can be readily assembled via this protocol.