作者:Jacek Skarżewski、Mariola Zielińska-Błajet、Małgorzata Kucharska
DOI:10.1055/s-2006-926382
日期:——
The native and epi-Cinchona alkaloids were reacted with (ArS)2/Bu3P in toluene at 65 °C to give the corresponding arylsulfanyl derivatives (15 examples, 31-75%) with complete inversion of configuration at 9-C stereogenic centers. Similar products were also obtained in the enantiospecific nucleophilic substitution of the 9-mesylates of alkaloids with sodium thiolates (4 examples, 73-84%) and no cinchona rearrangement was observed. The chiral thioethers obtained were preliminarily tested as N(sp3), S-donating chiral ligands in the Pd-catalyzed allylic alkylation of dimethyl malonate with rac-1,3-diphenylprop-2-enyl acetate and gave the product with up to 78% ee.
天然和表-金鸡纳生物碱与(ArS)2/Bu3P在甲苯中65°C反应,生成了相应的芳基硫醚衍生物(15个例子,收率31-75%),并且9-C立体中心完全发生了构型反转。类似的产物也通过生物碱的9-甲磺酸盐与硫醇盐的非对映选择性亲核取代反应得到(4个例子,收率73-84%),并且未观察到金鸡纳重排现象。获得的硫醚类化合物已作为N(sp3)、S供体的非手性配体进行初步测试,用于钯催化的亚磺酸二甲酯与消旋的1,3-二苯基丙-2-烯基乙酸酯的烯丙基烷基化反应,产物的对映体过量率高达78%。