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Hf(OTf)4-Catalyzed Three-Component Synthesis of N-Carbamate-Protected β-Amino Ketones.

ABSTRACT: Hafnium(IV) triflate (Hf(OTf)4) has been identified as a potent catalyst for the direct three-component synthesis of β-carbamate ketones. This new method, featuring a low catalyst loading, fast reaction rate, and solvent-free conditions, provided facile access to a diversity of carbamate-protected Mannich bases. A mechanistic investigation indicated that the three-component reaction proceeds via sequential aldol condensation and aza-Michael addition, but not the Mannich-type pathway.

SUBMITTER: Chen ZZ

PROVIDER: S-EPMC8840004 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Hf(OTf)4-Catalyzed Three-Component Synthesis of N-Carbamate-Protected β-Amino Ketones.

Chen Zhen-Zhen ZZ Yang Dong-Zhao DZ Dong Ying-Ying YY Chi Mei M Pu Shou-Zhi SZ Sun Qi Q

Molecules (Basel, Switzerland) 20220208 3

Hafnium(IV) triflate (Hf(OTf)4) has been identified as a potent catalyst for the direct three-component synthesis of β-carbamate ketones. This new method, featuring a low catalyst loading, fast reaction rate, and solvent-free conditions, provided facile access to a diversity of carbamate-protected Mannich bases. A mechanistic investigation indicated that the three-component reaction proceeds via sequential aldol condensation and aza-Michael addition, but not the Mannich-type pathway. ...[more]

PMID: 35164390

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