High diastereoselection in the intramolecular Diels–Alder reaction of o-quinodimethanes: an expedient entry to trans-benzoperhydrindans. A highly stereoselective total synthesis of (±)-estrone and (±)-adrenosterone

Abstract

A substituent effect on the diastereoselectivity of an Intramolecular Diels–Alder reaction of o-quinodimethanes has been studied and a highly diastereoselective synthesis of trans-benzoperhydrindan, which is a key intermediate for the synthesis of steroids, has been achieved by the thermolysis of 2-[2-(1,2-dihydro-4-methoxybenzocyclobuten-1-yl)ethyl]-2-isopropenyl-1,3-dioxolane, followed by acid hydrolysis of the initial product in quantitative yield. trans-Benzoperhydrindan was subsequently converted into (±)-estrone and (+)-adrenosterone.