An operationally simple and fully regiocontrolled formal total synthesis of the montanine-type Amaryllidaceae alkaloid (±)-pancracine

Abstract

Reaction of β-nitrostyrene 4 with cyclohexane-1,3-dione (5) in the presence of DBU affords the Michael-addition product 6, which is readily elaborated, using straightforward chemistry, to the 5,11-methanomorphanthridine 2, acquisition of which constitutes a formal total synthesis of the racemic modification of the montanine alkaloid pancracine (1).