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Nitrene-Mediated C-H Oxygenation: Catalytic Enantioselective Formation of Five-Membered Cyclic Organic Carbonates.

ABSTRACT: The synthesis of non-racemic 5-membered cyclic carbonates from abundant alcohols is reported. Conversion of the alcohol into an azanyl carbonate is followed by a chiral-at-ruthenium catalyzed cyclization to provide chiral cyclic carbonates in yields of up to 95 % and with up to 99 % ee. This new synthetic method is proposed to proceed through a nitrene-mediated intramolecular C(sp³ )-H oxygenation which includes an unusual 1,7-hydrogen atom transfer within a ruthenium nitrene intermediate. The method is applicable to the synthesis of non-racemic chiral mono-, di- and trisubstituted cyclic alkylene carbonates.

SUBMITTER: Nie X

PROVIDER: S-EPMC9827974 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Nitrene-Mediated C-H Oxygenation: Catalytic Enantioselective Formation of Five-Membered Cyclic Organic Carbonates.

Nie Xin X Ye Chen-Xi CX Ivlev Sergei I SI Meggers Eric E

Angewandte Chemie (International ed. in English) 20221026 48

The synthesis of non-racemic 5-membered cyclic carbonates from abundant alcohols is reported. Conversion of the alcohol into an azanyl carbonate is followed by a chiral-at-ruthenium catalyzed cyclization to provide chiral cyclic carbonates in yields of up to 95 % and with up to 99 % ee. This new synthetic method is proposed to proceed through a nitrene-mediated intramolecular C(sp<sup>3</sup> )-H oxygenation which includes an unusual 1,7-hydrogen atom transfer within a ruthenium nitrene intermed ...[more]

PMID: 36184573

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