One-Pot Benzoannulation of Homoallyl Alcohols: Vilsmeier Reaction Route to Biphenyls

Abstract

The Vilsmeier reaction of 4-aryl-1-penten-4-ols and of 1-allyl-1-hydroxytetralins (prepared from the appropriate ketones by Grignard reaction) provides a one-pot general route for the preparation of biphenyls and 9,10-dihydrophenanthrenes, respectively. From suitably substituted starting materials, biphenyl-4-carboxaldehydes and dihydrophenanthrene-10-carboxaldehydes can be isolated in addition.