Volume 63, Issue 13 e202318763
Research Article

Manganese-Catalyzed Mono-N-Methylation of Aliphatic Primary Amines without the Requirement of External High-Hydrogen Pressure

Jiale Ji

Jiale Ji

Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438 China

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Yinghao Huo

Yinghao Huo

Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438 China

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Zhaowen Dai

Zhaowen Dai

Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438 China

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Prof. Dr. Zhening Chen

Prof. Dr. Zhening Chen

State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, 350002 China.

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Prof. Dr. Tao Tu

Corresponding Author

Prof. Dr. Tao Tu

Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438 China

State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai, 200032 China

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First published: 01 February 2024
Citations: 6

Graphical Abstract

A synergistic strategy enables the selective synthesis of mono-N-methylated aliphatic primary amines, including deuterium-labelled drugs. This innovative approach combines an earth-abundant manganese catalyst with a weak base, resulting in a practical and sustainable protocol for mono-N-methylation. By effectively inhibiting the formation of formamide byproducts, it eliminates the need for external high-pressure hydrogen.

Abstract

The synthesis of mono-N-methylated aliphatic primary amines has traditionally been challenging, requiring noble metal catalysts and high-pressure H2 for achieving satisfactory yields and selectivity. Herein, we developed an approach for the selective coupling of methanol and aliphatic primary amines, without high-pressure hydrogen, using a manganese-based catalyst. Remarkably, up to 98 % yields with broad substrate scope were achieved at low catalyst loadings. Notably, due to the weak base-catalyzed alcoholysis of formamide intermediates, our novel protocol not only obviates the addition of high-pressure H2 but also prevents side secondary N-methylation, supported by control experiments and density functional theory calculations.

Conflict of interests

The authors declare no conflict of interest.

Data Availability Statement

The data that support the findings of this study are available in the supplementary material of this article.

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