Domino access to highly substituted chromans and isochromans from carbohydrates.

Herein we describe the synthesis of highly substituted chromans and isochromans using carbohydrates as starting materials. Our approach makes use of a Pd-catalyzed domino reaction consisting of oxidative addition, followed by two carbopalladation steps and completed by a cyclization to annelate the benzene moiety. The versatility of this route has been demonstrated by a small library of highly substituted chromans and isochromans.