350252-66-3Relevant academic research and scientific papers
Hydrogen-bonded dimers in dipyrrinones and acyldipyrrinones
Huggins,Lightner
, p. 203 - 221 (2007/10/03)
A crystal structure determination of the 9-acyl-dipyrrinone 9-butanoyl-2,3,7,8-tetramethyl-(10H)-dipyrrin-1-one indicates the presence of intermolecularly hydrogen-bonded dimers; however, in CHCl3 solution the pigment is monomeric as determined by vapor pressure osmometry measurements. Lacking an alkyl group at C(8), the 9-acyl-dipyrrinone exhibits only a weak tendency to form dimers in CHCl3 (KA ～ 60 M-1) as determined by analysis of variable temperature 1H NMR data. In contrast, when the 9-acyl group is replaced by formyl or when the acyl group is fixed in a syn orientation to the pyrrole NH, the dipyrrinone is strongly prone to dimerization in CHCl3.
