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Functionalized cyclopentenes through a tandem NHC-catalyzed dynamic kinetic resolution and ambient temperature decarboxylation: mechanistic insight and synthetic application.

ABSTRACT: An unusual room temperature ?-lactone decarboxylation facilitated a five-step enantioselective formal synthesis of the cyclopentane core of an estrogen receptor ?-agonist. A computational study probed the underlying factors facilitating unprecedented, rapid decarboxylation. Aryl substitution promotes faster reaction in the retro-[2+2] as a result of conjugative stabilization with the forming olefin. Additionally, the configuration of the ?-ester in these fused ?-lactones leads to differential decarboxylation rates.

SUBMITTER: Cohen DT

PROVIDER: S-EPMC4312178 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Functionalized cyclopentenes through a tandem NHC-catalyzed dynamic kinetic resolution and ambient temperature decarboxylation: mechanistic insight and synthetic application.

Cohen Daniel T DT Johnston Ryne C RC Rosson Nicholas T NT Cheong Paul Ha-Yeon PH Scheidt Karl A KA

Chemical communications (Cambridge, England) 20150201 13

An unusual room temperature β-lactone decarboxylation facilitated a five-step enantioselective formal synthesis of the cyclopentane core of an estrogen receptor β-agonist. A computational study probed the underlying factors facilitating unprecedented, rapid decarboxylation. Aryl substitution promotes faster reaction in the retro-[2+2] as a result of conjugative stabilization with the forming olefin. Additionally, the configuration of the α-ester in these fused β-lactones leads to differential de ...[more]

PMID: 25575249

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