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β-Silyloxy Allylboronate Esters through an Aldehyde Borylation/Homologation Sequence.

ABSTRACT: The areas of carbonyl borylation and the homologation of carbon-boron bonds have provided a number of fruitful methods in organic synthesis. Combining these approaches, the homologation of α-oxyboronate esters, provides pathways to access complex organoboronate esters stereoselectively. To this end, the homologation of α-silyloxyboronate esters with lithiated allyl chlorides to form β-silyloxy allylboronate esters is reported. Direct oxidation of the homologation products provides β-silyloxy allyl alcohols in good yield. The homologation provides a range of allylic alcohols, albeit with low diastereoselectivity.

SUBMITTER: Meyer GF

PROVIDER: S-EPMC7351078 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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β-Silyloxy Allylboronate Esters through an Aldehyde Borylation/Homologation Sequence.

Meyer Gillian F GF Nistler Maggie A MA Samoshin Andrey V AV McManus Brennan D BD Thane Taylor A TA Ferber Carl J CJ O'Neil Gregory W GW Clark Timothy B TB

Tetrahedron letters 20200529 28

The areas of carbonyl borylation and the homologation of carbon-boron bonds have provided a number of fruitful methods in organic synthesis. Combining these approaches, the homologation of α-oxyboronate esters, provides pathways to access complex organoboronate esters stereoselectively. To this end, the homologation of α-silyloxyboronate esters with lithiated allyl chlorides to form β-silyloxy allylboronate esters is reported. Direct oxidation of the homologation products provides β-silyloxy all ...[more]

PMID: 32655194

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