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Catalyst-controlled doubly enantioconvergent coupling of racemic alkyl nucleophiles and electrophiles.

ABSTRACT: Stereochemical control in the construction of carbon-carbon bonds between an alkyl electrophile and an alkyl nucleophile is a persistent challenge in organic synthesis. Classical substitution reactions via S_N1 and S_N2 pathways are limited in their ability to generate carbon-carbon bonds (inadequate scope, due to side reactions such as rearrangements and eliminations) and to control stereochemistry when beginning with readily available racemic starting materials (racemic products). Here, we report a chiral nickel catalyst that couples racemic electrophiles (propargylic halides) with racemic nucleophiles (?-zincated amides) to form carbon-carbon bonds in doubly stereoconvergent processes, affording a single stereoisomer of the product from two stereochemical mixtures of reactants.

SUBMITTER: Huo H

PROVIDER: S-EPMC7566878 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Catalyst-controlled doubly enantioconvergent coupling of racemic alkyl nucleophiles and electrophiles.

Huo Haohua H Gorsline Bradley J BJ Fu Gregory C GC

Science (New York, N.Y.) 20200101 6477

Stereochemical control in the construction of carbon-carbon bonds between an alkyl electrophile and an alkyl nucleophile is a persistent challenge in organic synthesis. Classical substitution reactions via S<sub>N</sub>1 and S<sub>N</sub>2 pathways are limited in their ability to generate carbon-carbon bonds (inadequate scope, due to side reactions such as rearrangements and eliminations) and to control stereochemistry when beginning with readily available racemic starting materials (racemic pro ...[more]

PMID: 32001652

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