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Tantalum ureate complexes for photocatalytic hydroaminoalkylation.

ABSTRACT: Using a tantalum ureate pre-catalyst, photocatalytic hydroaminoalkylation of unactivated alkenes with unprotected amines at room temperature is demonstrated. The combination of Ta(CH₂SiMe₃)₃Cl₂ and a ureate ligand with a saturated cyclic backbone resulted in this unique reactivity. Preliminary investigations of the reaction mechanism suggest that both the thermal and photocatalytic hydroaminoalkylation reactions begin with N-H bond activation and subsequent metallaaziridine formation. However, a select tantalum ureate complex, through ligand to metal charge transfer (LMCT), results in photocatalyzed homolytic metal-carbon bond cleavage and subsequent addition to unactivated alkene to afford the desired carbon-carbon bond formation. Origins of ligand effects on promoting homolytic metal-carbon bond cleavage are explored computationally to support enhanced ligand design efforts.

SUBMITTER: Hao H

PROVIDER: S-EPMC10171191 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Tantalum ureate complexes for photocatalytic hydroaminoalkylation.

Hao Han H Manßen Manfred M Schafer Laurel L LL

Chemical science 20230419 18

Using a tantalum ureate pre-catalyst, photocatalytic hydroaminoalkylation of unactivated alkenes with unprotected amines at room temperature is demonstrated. The combination of Ta(CH2SiMe3)3Cl2 and a ureate ligand with a saturated cyclic backbone resulted in this unique reactivity. Preliminary investigations of the reaction mechanism suggest that both the thermal and photocatalytic hydroaminoalkylation reactions begin with N-H bond activation and subse ...[more]

PMID: 37181785

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