An enantioselective assembly of naphthopyran via NHC-catalyzed [3 + 3] annulation of bromoenal with ß-tetralone.

ABSTRACT

An asymmetric assembly of naphthopyran was realized via the N-heterocyclic carbene (NHC)-catalyzed formal [3 + 3] annulation of bromoenal and ß-tetralone. The key advantages of this protocol include ready availability of starting materials, mild reaction conditions, good yields and excellent enantioselectivities.