Pyrrole-2-carboxylic ester, 1-phenyl

The Diels-Alder reaction of pyrrole-3-carboxylic esters with A-methyl- and N-phenyl-maleimides yield exclusively endo adducts.243 The Diels-Alder reaction of... 

By the hydrolysis of esters 81a-c, the corresponding acids 83a-c were formed. The 2-[3-(trifluoromethyl)phenyl]-4//-furo[3,2-7]pyrrole-5-carboxylic acid 83a was decarboxylated in acetic anhydride to 4-acetyl-2-[3-(trifluoromethyl)-phenyl]furo[3,2-7]pyrrole 84 (see 10.01.05.1.2, Scheme 7). 

A comparison of the absorption and fluorescence properties of 3,5-diaryl-l//-pyrrole-2-carboxylic acid ethyl esters reveals marked effects of/i-dimethylamino and o-methyl substituents on the phenyl group at C-3 and suggests that in the presence of these substituents emission occurs either from a charge transfer state or from a combination of charge transfer and locally excited states <2005NJC1258>. 

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