Stereoselective Dithiophosphorylation of Cinchona Alkaloids: Easy Approach to Prospective Chiral Ligands and Organocatalysts
Stereoselective Dithiophosphorylation of Cinchona Alkaloids: Easy Approach to Prospective Chiral Ligands and Organocatalysts
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DOI：
10.1080/10426507.2013.788000
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发表时间：
2013-04
期刊：
影响因子：
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通讯作者：
M. Zielińska-Błajet;J. Skarżewski
中科院分区：
文献类型：
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作者：
M. Zielińska-Błajet;J. Skarżewski
金鸡纳生物碱的9-甲磺酸酯与HSP（S）（OEt）2在苯中于50°C反应，得到相应的O，O-二乙基二硫代磷酸酯，其9-C立体异构中心构型完全反转（3个实例，产率42-45%）。还得到9-表奎宁的O-乙基-二硫代磷酸衍生物。立体异构中心的配置，建立使用homo和hetero-NOE NMR技术和比较实验和计算（GIAO/DFT）光谱。在钯催化的丙二酸二甲酯与外消旋-1，3-二苯基丙-2-烯基乙酸酯的烯丙基烷基化反应和铜催化的不对称亨利反应中，测试了生物碱的二硫代磷酸盐作为手性配体，并得到了各自的产物，纯度高达51%ee。奎宁O，O-二乙基-二硫代磷酸酯也被测试作为一种新的潜在的手性溶剂化剂的氨基酸（N-Boc-苯基甘氨酸）在31 P和1H NMR光谱。[本文有补充材料。请访问出版商的在线版《磷、硫、硅及相关元素》，查看免费补充文件：附加图]
Abstract The 9-mesylates of Cinchona alkaloids reacted with HSP(S)(OEt)2 in benzene at 50°C to give the corresponding O,O-diethyl-dithiophosphates of the alkaloids with complete inversion of configuration at the 9-C stereogenic centers (3 examples, 42–45% yields). Also O-ethyl-dithiophosphoric acid derivative of 9-epi-quinine was obtained. The configuration of the stereogenic centers were established using homo- and hetero-NOE NMR techniques and comparing the experimental and calculated (GIAO/DFT) spectra. The dithiophosphates of alkaloids were tested as chiral ligands in the Pd-catalyzed allylic alkylation of dimethyl malonate with rac-1,3-diphenylprop-2-enyl acetate and in the Cu-catalyzed asymmetric Henry reaction and gave the respective product with up to 51% ee. Quinine O,O-diethyl-phosphorodithioate was also tested as a novel potential chiral solvating agent for amino acids (N-Boc-phenylglycine) in 31P and 1H NMR spectroscopy. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental files: Additional figures] GRAPHICAL ABSTRACT