130222-56-9Relevant academic research and scientific papers
SYNTHESES OF UNSYMMETRICALLY SUBSTITUTED DIPYRROMETHANES BEARING A METHANE-CARBON SUBSTITUENT: INITIAL SYNTHETIC APPROACHES TO MESO-(METHOXYCARBONYLMETHYL)-PORPHYRINS RELATED TO CHLOROPHYLLA
Burns, Dennis H.,Smith, Kevin M.
, p. 1349 - 1372 (2007/10/02)
Methods are outlined for the synthesis of unsymmetrically substituted dipyrromethanes bearing an interpyrrolic substituent such as acetate.Condensation reactions between α-unsubstituted pyrroles and pyrrole α-acrylates in glacial acetic acid containing Amberlyst 15 resin and water afford the required acetate substituted dipyrromethanes in good yields; dipyrromethanes with interpyrrolic methyl and ethyl groups are similarly obtained from α-unsubstituted pyrroles and the corresponding α-vinylpyrrole or α-propenylpyrrole.More conveniently, use of the unsubstituted pyrroles and pyrrole acrylates in acetic acid containing a catalytic amount of trifluoroacetic acid gives the dipyrromethanes in good yield.In a model study, use of the MacDonald reaction (5,5'-diformyldipyrromethane condensation with a dipyrromethane-5,5'-dicarboxylic acid affords a 46percent yield of a pure porphyrin (5) in which the meso-acetic side chain is retained intact.
