Palladium-Catalyzed Intramolecular Cyclization of o-Ethynylbenzoic Acids and o-Ethynylbenzamides: Preparation of Isocoumarins and Isoquinolin-1-ones
摘要:
Treatment of the o-ethynylbenzoic acids 1A with a catalytic amount of Pd(II) and triethylamine resulted in the 6-endo-dig cyclization to give the 3-substituted isocoumarins 3 as major products in moderate to good yields. Similarly, the palladium-catalyzed cyclization of o-ethynylbenzamides 1B also proceeded but afforded only the isoquinolin-1-ones 3B.