Stereocontrolled synthesis of 1,5-stereogenic centers through three-carbon homologation of boronic esters.
نویسندگان
چکیده
Allylic pinacol boronic esters are stable toward 1,3-borotropic rearrangement. We developed a Pd(II)-mediated isomerization process that gives di- or trisubstituted allylic boronic esters with high E selectivity. The combination of this method with lithiation-borylation enables the synthesis of carbon chains that bear 1,5-stereogenic centers. The utility of this method has been demonstrated in a formal synthesis of (+)-jasplakinolide.
منابع مشابه
Homologation of boronic esters with lithiated epoxides for the stereocontrolled synthesis of 1,2- and 1,3-diols and 1,2,4-triols.
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1,2-Bis(boronic esters), derived from the enantioselective diboration of terminal alkenes, can be selectively homologated at the primary boronic ester by using enantioenriched primary/secondary lithiated carbamates or benzoates to give 1,3-bis(boronic esters), which can be subsequently oxidized to the corresponding secondary-secondary and secondary-tertiary 1,3-diols with full stereocontrol. Th...
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عنوان ژورنال:
- Angewandte Chemie
دوره 53 37 شماره
صفحات -
تاریخ انتشار 2014