6-exo versus 7-endo iodolactonizations of 2-(alkynyl)phenylacetic acids
摘要:
Exposure of 2-alkynylphenylacetic acids to excess iodine in acetonitrile containing anhydrous potassium carbonate delivers good yields, either of the corresponding isochroman-3-ones or benzo[d]oxepin-2(1H)-ones, depending upon the alkyne substituent: when this is alkyl, the former 6-exo products dominate, Otherwise the 7-endo products are formed largely or, more often, exclusively. (C) 2009 Elsevier Ltd. All rights reserved.
6-exo versus 7-endo iodolactonizations of 2-(alkynyl)phenylacetic acids
摘要:
Exposure of 2-alkynylphenylacetic acids to excess iodine in acetonitrile containing anhydrous potassium carbonate delivers good yields, either of the corresponding isochroman-3-ones or benzo[d]oxepin-2(1H)-ones, depending upon the alkyne substituent: when this is alkyl, the former 6-exo products dominate, Otherwise the 7-endo products are formed largely or, more often, exclusively. (C) 2009 Elsevier Ltd. All rights reserved.