A conceptually new route to optically active carba-prostacyclins: synthesis of exocyclic alkenes via doubly lithiated allyl sulfones
作者:Hans-Joachim Gais、Walter A. Ball、Jörg Bund
DOI:10.1016/s0040-4039(00)80208-7
日期:1988.1
substitution provides a novel synthon for 1.1-dilithioalkenes. Starting from the enantiomerically pure dimesylate 5b and using 6 a conceptually new route to optically active carbaprostacyclins 2 via the bicyclic allyl sulfones 2S/2R-7 and their substitution with the cuprate 8 to the alkenes E/Z-9 has been realized. Substitution of 11 with 2-3 equiv RLi proceeds via the o-lithioaryl sulfone 14 to yield rac-13
分别将o,α-和α,α-二石硫砜6和16用于双环烷基化,然后用铜酸盐取代,为1.1-二硫代烯烃提供了新的合成子。从对映体纯的二甲基磺酸盐5b开始,并使用6,从概念上讲,是通过双环烯丙基砜2S / 2R-7制备旋光的碳环前环素2的新途径,并且已将它们用铜酸盐8取代为烯烃E / Z-9。通过邻-硫代芳基砜14进行的1-3当量RLi取代11产生rac - 13。16与二甲基磺酸酯10的环烷基化提供了烷基烯丙基砜17,当被8取代时,它也产生rac -13 。