A mild and convenient one-pot photochemical synthesis of chroman-4-one derivatives. The photo-Fries rearrangement of (hetero)aryl 3-methyl-2-butenoate esters under basic catalysis

C. SAMANIEGO LOPEZ, R. ERRA-BALSELLS AND S. M. BONESI

TETRAHEDRON LETTERS

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2010 vol. 51 p. 4387 - 4390

0040-4039

a b s t r a c t The biphasic base catalysis-mediated photo-Fries rearrangement reaction of aryl 3-methy-2-butenoate esters in room temperature cyclohexane—10% KOH system was investigated. This mild photochemical reaction leads to the formation of chroman-4-one derivatives in good to high yield and in short reaction times (30–120 min) in a one-pot photochemical reaction. Also, the photochemical reaction, as a convenient, versatile, and general method, applies efficiently to polycyclic and heterocyclic 3-methy-2-butenaote esters. 2010 Elsevier Ltd. All rights reserved.2010 Elsevier Ltd. All rights reserved.