Optimisation of enantioselectivity for the chiral base-mediated rearrangement of bis-protected meso-4,5-dihydroxycyclohexene oxides: asymmetric synthesis of 4-deoxyconduritols and conduritol F
作者:Simon E de Sousa、Peter O'Brien、Christopher D Pilgram
DOI:10.1016/s0040-4020(02)00370-8
日期:2002.6
based on diastereoselective epoxidation of a cyclohexene followed by chiral lithium amide-mediated epoxide rearrangement has been used to synthesise an allylic alcoholbuildingblock of >95% ee. The key step is the enantioselective rearrangement of a bis-protected meso-4,5-dihydroxycyclohexene oxide. A range of protecting groups and chiral base structures were surveyed in order to find the optimum protocol
Chiral base route to cyclic polyols: asymmetric synthesis of aminodeoxyconduritols and conduritol F
作者:Simon E de Sousa、Peter O'Brien、Christopher D Pilgram
DOI:10.1016/s0040-4039(01)01706-3
日期:2001.11
A chiral base route from a meso cyclohexene oxide to an allylic alcohol provides key intermediates for the synthesis of cyclic polyols. A Mitsunobu approach and an Overman rearrangement approach transform allylic alcohols into some aminodeoxyconduritols (95% ee). Elaboration of a chiral enone (89% ee) via (i) α-hydroxylation and (ii) stereoselective reduction completes a high yielding synthesis of