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Chemoselective carbene insertion into the N-H bonds of NH₃·H₂O.

ABSTRACT: The conversion of inexpensive aqueous ammonia (NH₃·H₂O) into value-added primary amines by N-H insertion persists as a longstanding challenge in chemistry because of the tendency of Lewis basic ammonia (NH₃) to bind and inhibit metal catalysts. Herein, we report a chemoselective carbene N-H insertion of NH₃·H₂O using a Tp^Br3Ag-catalyzed two-phase system. Coordination by a homoscorpionate Tp^Br3 ligand renders silver compatible with NH₃ and H₂O and enables the generation of electrophilic silver carbene. Water promotes subsequent [1,2]-proton shift to generate N-H insertion products with high chemoselectivity. The result of the reaction is the coupling of an inorganic nitrogen source with either diazo compounds or N-triftosylhydrazones to produce useful primary amines. Further investigations elucidate the reaction mechanism and the origin of chemoselectivity.

SUBMITTER: Liu Z

PROVIDER: S-EPMC9741638 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Chemoselective carbene insertion into the N-H bonds of NH3·H2O.

Liu Zhaohong Z Yang Yong Y Song Qingmin Q Li Linxuan L Zanoni Giuseppe G Liu Shaopeng S Xiang Meng M Anderson Edward A EA Bi Xihe X

Nature communications 20221210 1

The conversion of inexpensive aqueous ammonia (NH3·H2O) into value-added primary amines by N-H insertion persists as a longstanding challenge in chemistry because of the tendency of Lewis basic ammonia (NH3) to bind and inhibit metal catalysts. Herein, we report a chemoselective carbene N-H insertion of NH3·H2O using a TpBr3Ag-catalyzed two-phase system. Coordination by a homoscorpionate TpBr3 ligand renders silver comp ...[more]

PMID: 36496464

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