Regio‐ and Stereoselective Homologation of 1,2‐Bis(Boronic Esters): Stereocontrolled Synthesis of 1,3‐Diols and Sch 725674
نویسندگان
چکیده
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. The transformation was applied to a concise total synthesis of the 14-membered macrolactone, Sch 725674. The nine-step synthetic route also features a novel desymmetrizing enantioselective diboration of a divinyl carbinol derivative and high-yielding late-stage cross-metathesis and Yamaguchi macrolactonization reactions.
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.
Lithiated epoxides react stereospecifically with boronic esters to give syn-1,2-diols, a process that can be used iteratively to create triols containing four stereogenic centers.
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