Preparation of chiral indanones and dihydrocoumarins; Application to synthesis of (+)-3-(2,6-dimethoxyphenyl) pentanoic acid

Article abstract of DOI:10.1016/S0957-4166(00)80481-4

Chiral β-aryl carboxylic acids, prepared by Michael addition of organocuprates to chiral unsaturated imides, are transformed into chiral 3- alkyl-4-benzoyloxyindan-1-ones via two intramolecular acylations, with intermediate formation of chiral 3-alkylindanones and corresponding dihydrocoumarins. The 3-(S)-ethyl-4-benzoyloxyindanone is transformed into(+)-3-(S)-(2,6-dimethoxyphenyl)pentanoic acid.