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Hf(OTf)4 as a Highly Potent Catalyst for the Synthesis of Mannich Bases under Solvent-Free Conditions.

ABSTRACT: Hf(OTf)4 was identified as a highly potent catalyst (0.1-0.5 mol%) for three-component Mannich reaction under solvent-free conditions. Hf(OTf)4-catalyzed Mannich reaction exhibited excellent regioselectivity and diastereoselectivity when alkyl ketones were employed as substrates. 1H NMR tracing of the H/D exchange reaction of ketones in MeOH-d4 indicated that Hf(OTf)4 could significantly promote the keto-enol tautomerization, thereby contributing to the acceleration of reaction rate.

SUBMITTER: Han SB

PROVIDER: S-EPMC7024362 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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