John G Angeles

Publications (2)8.9 Total impact

• Article: Indanones and indenols from 2-alkylcinnamaldehydes via the intramolecular Friedel-Crafts reaction of geminal diacetates.

  Gary B Womack, John G Angeles, Vincent E Fanelli, Brinda Indradas, Roger L Snowden, Philippe Sonnay
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  ABSTRACT: When treated with Ac2O at rt in the presence of 4-6 mol % FeCl3, 2-alkylcinnamaldehydes are converted to 2-alkyl-1H-inden-1-yl acetates through the intermediacy of gem-diacetates. Methanolysis of the indenyl acetates yields the corresponding indenols. Saponification yields 2-alkylindanones, providing, in effect, an intramolecular acylation employing catalytic levels of acid.
  The Journal of Organic Chemistry 08/2009; 74(15):5738-41. · 4.45 Impact Factor
• Article: Conversion of 2-alkylcinnamaldehydes to 2-alkylindanones via a catalytic intramolecular Friedel-Crafts reaction.

  Gary B Womack, John G Angeles, Vincent E Fanelli, Christie A Heyer
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  ABSTRACT: The preparation of indanones by the intramolecular acylation of 3-arylpropanoic acids or halides requires the use of noncatalytic acid promoters. In the presence of 5-10 mol % FeCl(3), in situ generated dimethyl acetals of (E)-2-alkylcinnamaldehydes cyclize to 1-methoxy-2-alkyl-1H-indenes in good-to-high yields. The 1-methoxyindenes were converted in high yield into 2-alkylindanones by treatment with triethylamine, to effect isomerization to the isomeric enol ethers, followed by acid-catalyzed hydrolysis. Thus, a catalytic, intramolecular Friedel-Crafts reaction leading to 2-alkylindanones from 2-alkylcinnamaldehydes was developed.
  The Journal of Organic Chemistry 09/2007; 72(18):7046-9. · 4.45 Impact Factor