The axially chiral title compound was enantiomerically resolved by the diastereomer method via the camphorsultamamide of the corresponding dicarboxylic acid. The absolute stereochemistry of the (+)- and (−)-forms ([α]D +32 and −33) was determined by X-ray analysis of one of the diastereomers of the sultamamide to be P and M, respectively, for the helicity about the C9–C9′ bond. The observed CD and UV spectra were reasonably reproduced by the theoretical calculation based on the time-dependent density functional theory (TDDFT). The CD spectrum of the (M)-(−) form features a split curve around 270 nm assignable to the exciton coupling of the β transition and a broad p band peak around 380 nm.
通过相应二羧酸的樟脑磺酰胺,采用非对映异构体法对轴向手性标题化合物进行了对映体解析。通过对其中一种非对映异构体的 X 射线分析,确定了 (+)- 和 (-)- 形式([α]D +32 和 -33)的绝对立体化学性质,即围绕 C9-C9′ 键的螺旋度分别为 P 和 M。基于时间相关密度泛函理论(TDDFT)的理论计算合理地再现了观察到的 CD 和 UV 光谱。(M)-(-)形式的 CD 光谱在 270 nm 附近有一条分裂曲线,这可能与 β 转变的激子耦合有关,而在 380 nm 附近则有一个宽 p 带峰值。