2-Benzoylethynyl-5-phenylpyrrole

Benzoylethynyl)-5-phenylpyrrole, synthesized from 2-phenylpyrrole and benzoylbromoacetylene on alumina surface, crystallizes (after chromatography on AI2O3) in two visually distinctive forms (prisms and needles), which represent the cis- and trani -rotamers relative to mutual disposition of the nitrogen atom and the carbonyl group (x-ray analysis data) [515],... 

The general view of trans-rotamer of 2-(2-benzoylethynyl)-5-phenylpyrrole... 

Benzoylethynyl)-5-phenylpyrrole, prepared from 2-(2-benzoyl-l-bromovinyl)-5-phenylpyrrole on the Zr02, crystallizes mostly as prisms (ds-rotamer, x-ray analysis) upon passing through AI2O3 [519]. 

Trofimov, B.A., Z.V. Stepanova, L.N. Sobenina et al. 2005. 2-(2-Benzoylethynyl)-5-phenylpyrrole Fixation of cis- and frans-rotamers in crystal state. Mendeleev Commun 6 229-232. 

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