Date Published: May 01, 2012
Publisher: International Union of Crystallography
Author(s): Qing-yu Li, Rui Guo, Zhi-hong Xu.
The title compound, C33H34N4O2S·CH3OH, was prepared as a spirolactam ring formation of rhodamine 6 G dye for comparison with a ring-opened form. The xanthene and spirolactam rings are approximately planar [r.m.s. deviations from planarity = 0.122 (3) and 0.072 (6) Å, respectively]. The dihedral angles formed by the spirolactam and thiophene rings with the xanthene ring system are 89.7 (6) and 86.5 (2)°, respectively. The crystal structure features N—H⋯O and C—H⋯O hydrogen bonds.
For rhodamine derivatives bearing a lactam moiety, see: Tian & Peng (2008 ▶); Wu et al. (2007 ▶); Xi et al. (2011 ▶); Xu et al. (2009 ▶, 2011 ▶); Xu, Guo et al. (2010 ▶); Xu, Zhang et al. (2010 ▶); Zhang et al. (2008 ▶).