Zhang Yulong, Zhao Peichao, Sun Shengnan, Wu Qian, Shi Enxue, Xiao Junhua
State Key Laboratory of NBC Protection for Civilian, Beijing, China.
Commun Chem. 2023 Jun 27;6(1):133. doi: 10.1038/s42004-023-00935-0.
The access to P-stereogenic motifs has always been considered a very challenging and high attractive mission in modern organic synthesis. While several chiral auxiliaries employed by the practical Jugé-Stephan-like methodology have been developed, new type of readily accessible bifunctional ligands toward P-stereogenic building still remain much desirable. Herein, we present a powerful chiral template, camphor-derived 2,3-diols named CAMDOL, which were designed and synthesized from the commercially cheap camphorquinone in high yields at 50 grams scale with a column-free purification. Diverse P(III)-chiral compounds and their borane forms including phosphinous acids, phosphinites, and phosphines, as well as the corresponding P(V)-chiral compounds including phosphinates, phosphine oxides, phosphinothioates, phosphine sulfides, and secondary phosphine oxides were afforded in high yields and ee values through the optimal 2,3-diphenyl CAMDOL platform. An unusual C-OP bond cleavage following the first P-OC bond breaking was observed during the ring-opening process when quenching by NHCl solution, which generates a unique but valuable camphor-epoxide scaffold as by-product.
在现代有机合成中，获取P-手性基序一直被认为是一项极具挑战性且极具吸引力的任务。虽然已经开发了几种通过类似Jugé-Stephan实用方法使用的手性助剂，但对于P-手性结构单元而言，新型易于获得的双功能配体仍然非常需要。在此，我们展示了一种强大的手性模板，即樟脑衍生的2,3-二醇，命名为CAMDOL，它是由市售廉价的樟脑醌设计并以50克规模高产率合成的，无需柱色谱纯化。通过优化的2,3-二苯基CAMDOL平台，以高产率和对映体过量值得到了多种P(III)-手性化合物及其硼烷形式，包括亚膦酸、亚膦酸酯和膦，以及相应的P(V)-手性化合物，包括次膦酸酯、氧化膦、硫代膦酸酯、硫化膦和仲氧化膦。在用NHCl溶液淬灭时，在开环过程中观察到在第一个P-OC键断裂后出现了不寻常的C-OP键断裂，生成了一种独特但有价值的樟脑环氧化物支架作为副产物。
