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Phosphine-Catalyzed Intramolecular Cyclizations of ?-Nitroethylallenoates Forming (Z)-Furanone Oximes.

ABSTRACT: A novel and efficient phosphine-catalyzed intramolecular cyclization of ?-nitroethylallenic esters is reported. This process appears to be practical for the stereoselective syntheses of (Z)-furan-2(3H)-one oxime derivatives in excellent yields. Mechanistically, the reaction involves a phosphine-catalyzed Michael addition of an alkylideneazinate and rearrangement of the cyclic nitronate to the ?-nitrosodihydrofuran.

SUBMITTER: Zhou QF

PROVIDER: S-EPMC4922534 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Phosphine-Catalyzed Intramolecular Cyclizations of α-Nitroethylallenoates Forming (Z)-Furanone Oximes.

Zhou Qing-Fa QF Zhang Kui K Cai Lingchao L Kwon Ohyun O

Organic letters 20160527 12

A novel and efficient phosphine-catalyzed intramolecular cyclization of α-nitroethylallenic esters is reported. This process appears to be practical for the stereoselective syntheses of (Z)-furan-2(3H)-one oxime derivatives in excellent yields. Mechanistically, the reaction involves a phosphine-catalyzed Michael addition of an alkylideneazinate and rearrangement of the cyclic nitronate to the α-nitrosodihydrofuran. ...[more]

PMID: 27232451

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