Shim Sang Chul, Kim Dong Suk, Yoo Dong Jin, Wada Takehiko, Inoue Yoshihisa
Center for Molecular Design and Synthesis, Department of Chemistry and School of Molecular Science (BK-21), Korea Advanced Institute of Science and Technology (KAIST), 373-1 Guseong-Dong, Yuseong-Gu, Daejeon 305-701, Korea.
J Org Chem. 2002 Aug 9;67(16):5718-26. doi: 10.1021/jo025782o.
Highly diastereodifferentiating bimolecular asymmetric photoreaction was achieved in the photosensitized polar addition of methanol to (R)-(+)-limonene. The diastereomeric excess (de) of the photoadduct could be controlled and fine-tuned by changing the internal/external factors such as solvent polarity, reaction temperature, and structure of the sensitizers. The de increased from 23% obtained upon xylene photosensitization in pure methanol at room temperature to >96% upon singlet sensitization with methyl benzoate at -75 degrees C in 0.5 M methanol/diethyl ether solution.
在甲醇对（R）-（+）-柠檬烯的光敏性极性加成反应中，实现了高度的非对映体选择性双分子不对称光反应。通过改变诸如溶剂极性、反应温度和敏化剂结构等内部/外部因素，可以控制和微调光加合物的非对映体过量（de）。非对映体过量从室温下在纯甲醇中用二甲苯敏化时得到的23%增加到在-75℃下于0.5M甲醇/乙醚溶液中用苯甲酸甲酯进行单重态敏化时的>96%。
