Wang Yifeng, Zhang Wei, Xu Xiangsheng, Zhang Guangcun
State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.
Acta Crystallogr Sect E Struct Rep Online. 2009 Dec 19;66(Pt 1):o217. doi: 10.1107/S1600536809051976.
The title compound, C(21)H(17)ClO(6), is optically pure and adopts an R configuration. It was obtained by an organocatalytic asymmetric Michael addition of 4-hydroxy-coumarin with (E)-ethyl 4-(4-chloro-phen-yl)-2-oxobut-3-enoate. The structure consists of a tetra-hydro-pyran unit fused to the coumarin ring ring system. The hydroxyl and phenyl groups are on the same side of the tetra-hydro-pyrane ring. The benzene ring is almost perpendicular to the coumarin ring [dihedral angle of 72.89 (3)°]. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds are observed. An intra-molecular O-H⋯O contact also occurs.
标题化合物C(21)H(17)ClO(6)为光学纯，呈R构型。它是通过4-羟基香豆素与(E)-4-(4-氯苯基)-2-氧代丁-3-烯酸乙酯的有机催化不对称迈克尔加成反应制得的。该结构由一个与香豆素环系统稠合的四氢吡喃单元组成。羟基和苯基位于四氢吡喃环的同一侧。苯环几乎垂直于香豆素环[二面角为72.89 (3)°]。在晶体结构中，观察到分子间O-H⋯O氢键。还存在分子内O-H⋯O接触。
