Anthraquinone substituted by 2-methyl-1-naphthyl groups in positions 1,8 yields syn (meso) and anti (racemic) isomers (red and yellow colored, respectively) that interconvert with a barrier of 35.4 kcal mol-1 in solution. Their structures were identified by NOE experiment in solution and X-ray diffraction in the solids. The racemic anti form (C2 point group) entails two atropisomers that were separated by enantioselective HPLC: the absolute configuration was assigned by TD-DFT simulation of the ECD spectrum. Two atropisomers were also separated and assigned in the case of anthraquinone bearing a single 2-methyl-1-naphthyl substituent in position 1.
Structure, Stereodynamics and Absolute Configuration of the Atropisomers of Hindered Arylanthraquinones
LUNAZZI, LODOVICO;MANCINELLI, MICHELE;MAZZANTI, ANDREA
2009
Abstract
Anthraquinone substituted by 2-methyl-1-naphthyl groups in positions 1,8 yields syn (meso) and anti (racemic) isomers (red and yellow colored, respectively) that interconvert with a barrier of 35.4 kcal mol-1 in solution. Their structures were identified by NOE experiment in solution and X-ray diffraction in the solids. The racemic anti form (C2 point group) entails two atropisomers that were separated by enantioselective HPLC: the absolute configuration was assigned by TD-DFT simulation of the ECD spectrum. Two atropisomers were also separated and assigned in the case of anthraquinone bearing a single 2-methyl-1-naphthyl substituent in position 1.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
