Reference

Unusual sensitivity to the concentration of ethanol in the boron trifluoride/ethanol-catalyzed synthesis of 5,10,15,20-tetrakis(4-cyano-2,6-dimethylphenyl)porphyrin by the Lindsey method

Unusual sensitivity to the concentration of ethanol in the boron trifluoride/ethanol-catalyzed synthesis of 5,10,15,20-tetrakis(4-cyano-2,6-dimethylphenyl)porphyrin by the Lindsey method. Steiger, Beat; Anson, Fred C. (Aurthur Amos Noyes Laboratories, California Institute of Technology, Pasadena, CA 91125, USA). Journal of Heterocyclic Chemistry, 34(1), 269-272 (English) 1997 HeteroCorporation. CODEN: JHTCAD. ISSN: 0022-152X. DOCUMENT TYPE: Journal CA Section: 26 (Biomolecules and Their Synthetic Analogs) The boron trifluoride/ethanol-catalyzed condensation of 4-cyano-2,6-dimethylbenzaldehyde (I) with pyrrole by the Lindsey method to give the new, ortho-disubstituted 5,10,15,20-tetrakis(4-cyano-2,6-dimethylphenyl)porphyrin (II) was found to be highly sensitive to the concn. of ethanol. In the absence of ethanol the yield of porphyrin is only 1%. Yields can be increased to 20-25% with ethanol concns. of 0.05-0.1% (vol./vol.) but they decrease rapidly at higher concns. of ethanol. 74896-24-5 and 24596-19-8 which are cas registry numbers of substances are two of reagents here. Optimized procedures for the prepn. of both I and II are described and the newly synthesized mols. are characterized by NMR (1H and 13C), mass spectra and elemental anal. .