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Silver-Catalyzed Regio- and Stereoselective Formal Carbene Insertion into Unstrained C-C ?-Bonds of 1,3-Dicarbonyls.

ABSTRACT: A regio- and stereoselective silver-catalyzed formal carbene insertion into 1,3-dicarbonyls has been developed, using N-nosylhydrazones as diazo surrogates. Two new C-C bonds are constructed at the carbenic carbon center through the selective cleavage of the C-C(=O) ?-bond of acyclic 1,3-dicarbonyls, enabling the preparation of various synthetically useful polysubstituted ?-diketones, ?-ketoesters, and ?-ketoamides in high yields. The in situ formation of a donor-acceptor cyclopropane, via reaction of the enolate of the 1,3-dicarbonyl with an electrophilic silver carbenoid, is proposed as a key process in the catalytic cycle.

SUBMITTER: Liu Z

PROVIDER: S-EPMC6170519 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Silver-Catalyzed Regio- and Stereoselective Formal Carbene Insertion into Unstrained C-C σ-Bonds of 1,3-Dicarbonyls.

Liu Zhaohong Z Zhang Xinyu X Virelli Matteo M Zanoni Giuseppe G Anderson Edward A EA Bi Xihe X

iScience 20180918

A regio- and stereoselective silver-catalyzed formal carbene insertion into 1,3-dicarbonyls has been developed, using N-nosylhydrazones as diazo surrogates. Two new C-C bonds are constructed at the carbenic carbon center through the selective cleavage of the C-C(=O) σ-bond of acyclic 1,3-dicarbonyls, enabling the preparation of various synthetically useful polysubstituted γ-diketones, γ-ketoesters, and γ-ketoamides in high yields. The in situ formation of a donor-acceptor cyclopropane, via react ...[more]

PMID: 30278300

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