Synthesis of meso-Tetrakis(4-chlorocoumarin-3-yl)porphyrins

Abstract

meso-Tetrakis(4-chlorocoumarin-3-yl)porphyrins were prepared by condensation of corresponding 4- chlorocoumarin-3-carboxaldehydes and pyrrole in the presence of trifluoro acetic acid (TFA) in dichloromethane followed by oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). These porphyrins exhibited the atropisomerism due to ortho substituent of meso aryl groups. The atropisomers of meso-tetrakis(4-chloro-6-methylcoumarin-3-yl)porphyrin were separated and identified by 1H-nmr spectra. Zinc complexes of these porphyrins were synthesized and characterized by ms, 1H nmr, ir and uv-vis spectra.