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Direct stereospecific synthesis of unprotected N-H and N-Me aziridines from olefins.

ABSTRACT: Despite the prevalence of the N-H aziridine motif in bioactive natural products and the clear advantages of this unprotected parent structure over N-protected derivatives as a synthetic building block, no practical methods have emerged for direct synthesis of this compound class from unfunctionalized olefins. Here, we present a mild, versatile method for the direct stereospecific conversion of structurally diverse mono-, di-, tri-, and tetrasubstituted olefins to N-H aziridines using O-(2,4-dinitrophenyl)hydroxylamine (DPH) via homogeneous rhodium catalysis with no external oxidants. This method is operationally simple (i.e., one-pot), scalable, and fast at ambient temperature, furnishing N-H aziridines in good-to-excellent yields. Likewise, N-alkyl aziridines are prepared from N-alkylated DPH derivatives. Quantum-mechanical calculations suggest a plausible Rh-nitrene pathway.

SUBMITTER: Jat JL

PROVIDER: S-EPMC4175444 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Direct stereospecific synthesis of unprotected N-H and N-Me aziridines from olefins.

Jat Jawahar L JL Paudyal Mahesh P MP Gao Hongyin H Xu Qing-Long QL Yousufuddin Muhammed M Devarajan Deepa D Ess Daniel H DH Kürti László L Falck John R JR

Science (New York, N.Y.) 20140101 6166

Despite the prevalence of the N-H aziridine motif in bioactive natural products and the clear advantages of this unprotected parent structure over N-protected derivatives as a synthetic building block, no practical methods have emerged for direct synthesis of this compound class from unfunctionalized olefins. Here, we present a mild, versatile method for the direct stereospecific conversion of structurally diverse mono-, di-, tri-, and tetrasubstituted olefins to N-H aziridines using O-(2,4-dini ...[more]

PMID: 24385626

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