• Synthetic studies in cinnamylated derivatives of resacetophenone and related compounds

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    • Keywords

       

      C- andO-cinnamylation; Claisen rearrangement; 1-phenyl-1-propenyl and 1-phenyl-allyl derivatives

    • Abstract

       

      Resacetophenone (1) reacts with cinnamyl bromide in the presence of K2CO3 and acetone to give its 4-O-cinnamyl derivative (2); whereas the same reaction in the presence of methanolic methoxide affords 3-C-cinnamyl-(6), 5-C-cinnamyl-(8) and 3,5-di-C-C-cinnamyl- (4) derivatives in the ratio of 36∶1∶15. Reaction of 1 with cinnamyl alcohol in boiling formic acid results in the formation of 8 in the largest amount followed by 6 and a new compound which is a mono-C-cinnamyl flavan (10 or 11). 6 was converted into the corresponding flavan (12), flavene (13) and 4-hydroxycoumarin (14).

      On Claisen rearrangement yielded a mixture of three compounds, two of which were found to be the normal products viz. 3-(1-phenyl-allyl) resacetophenone (18) and its 5-isomer (19). The third but major compound was the further rearranged but uncyclised 3-(1-phenyl-1-propenyl) derivative (15) which forms the corresponding chalcone (21) when condensed with anisaldehyde in the presence of alkali.

    • Author Affiliations

       

      A C Jain1 A Kumar1 R C Gupta1

      1. Department of Chemistry, Himachal Pradesh University, Simla - 171 005
    • Dates

       
  • Journal of Chemical Sciences | News

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