Photocyclisation of enamides. Part 29. A general strategy for the synthesis of ipecac and heteroyohimbine alkaloids

Abstract
The synthesis of the ester (12) and lactone (19)via reductive photocyclisation of the enamide (3), kinetically controlled alkylation of the furopyridone (4), and reductive cleavage of the γ-lactones (10) and (14) illustrates a new general method for the preparation of the ipecac and heteroyohimbine alkaloids.