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Catalytic Enantioselective [3 + 2] Cycloaddition of ?-Keto Ester Enolates and Nitrile Oxides.

ABSTRACT: An enantioselective [3 + 2] cycloaddition reaction between nitrile oxides and transiently generated enolates of ?-keto esters has been developed. The catalyst system was found to be compatible with in situ nitrile oxide-generation conditions. A versatile array of nitrile oxides and ?-keto esters could participate in the cycloaddition, providing novel 5-hydroxy-2-isoxazolines in high chemical yield with high levels of diastereo- and enantioselectivity. Notably, the optimal reaction conditions circumvented concurrent reactions via O-imidoylation and hetero-[3 + 2] pathways.

SUBMITTER: Bartlett SL

PROVIDER: S-EPMC5547566 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Catalytic Enantioselective [3 + 2] Cycloaddition of α-Keto Ester Enolates and Nitrile Oxides.

Bartlett Samuel L SL Sohtome Yoshihiro Y Hashizume Daisuke D White Peter S PS Sawamura Miki M Johnson Jeffrey S JS Sodeoka Mikiko M

Journal of the American Chemical Society 20170615 25

An enantioselective [3 + 2] cycloaddition reaction between nitrile oxides and transiently generated enolates of α-keto esters has been developed. The catalyst system was found to be compatible with in situ nitrile oxide-generation conditions. A versatile array of nitrile oxides and α-keto esters could participate in the cycloaddition, providing novel 5-hydroxy-2-isoxazolines in high chemical yield with high levels of diastereo- and enantioselectivity. Notably, the optimal reaction conditions cir ...[more]

PMID: 28581747

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