Reactivity of Pyrrole Pigments, 4. Part: Deuteration of 5-Arylmethylene-3-pyrrolin-2-ones with d1-Trifluoroacetic Acid

Article abstract of DOI:10.1007/BF00799033

5-Arylmethylene-3,4-dimethyl-3-pyrrolin-2-ones on treatment with d1-trifluoroacetic acid (d1-TFA) undergo deuterium substitution at the carbon atom of the methylene bridge.This electrophilic substitution is related to similar deuteration reactions of verdins (bilatrienes-a,b,c).The results obtained can be interpreted by a free energy relationship, assuming that the field effect, becomes negligible by the influence of TFA. - Keywords: Bile pigments; Deuteration; Trifluoroacetic acid; Field effect; FMMF method