Tian Jie, Meng Xin, Sun Hao, Chen Qian, Xu Qian, Dai Pinli, Li Linlin, Zhang Lin, Li Chun
State Key Laboratory of Functions and Applications of Medicinal Plants and School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550004, People's Republic of China.
J Org Chem. 2023 Jul 7;88(13):9213-9224. doi: 10.1021/acs.joc.3c00786. Epub 2023 May 25.
A concise synthesis of cinchona-alkaloid-derived NN ligands bearing alkyl substituents on chiral nitrogen atoms was described. Iridium catalysts containing new chiral NN ligands and achiral phosphines were effective for the asymmetric hydrogenation of heteroaromatic ketones, which afforded corresponding alcohols in up to 99.9% ee. The same protocol was applicable to the asymmetric hydrogenation of α-chloroheteroaryl ketones. Most importantly, the gram-scale asymmetric hydrogenation of 2-acetylthiophene and 2-acetylfuran proceeded smoothly even under 1 MPa of H.
描述了一种在氮原子上带有烷基取代基的金鸡纳生物碱衍生的NN配体的简洁合成方法。含有新型手性NN配体和非手性膦的铱催化剂对杂芳基酮的不对称氢化反应有效，可得到对映体过量高达99.9%的相应醇类。相同的方法适用于α-氯杂芳基酮的不对称氢化反应。最重要的是，即使在1MPa氢气压力下，2-乙酰基噻吩和2-乙酰基呋喃的克级不对称氢化反应也能顺利进行。
