Photocyclisation of enamides. Part 24. Total synthesis of (±)-isofumigaclavine B and (±)-lysergic acid

Total syntheses of two ergoiine-types of alkaloids, (±)-isofumigaclavine B (14)(for the first time) and methyl (±)-Iysergate (21) and methyl (±)-isolysergate (22), via a route involving reductive photocyclisation of the enamide (2) followed by glycol formation and oxidative cleavage of the dihydrofuran ring, are described.