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Manganese-Catalyzed β-Methylation of Alcohols by Methanol.

ABSTRACT: We report an earth-abundant-metal-catalyzed double and single methylation of alcohols. A manganese catalyst, which operates at low catalyst loadings and short reaction times, mediates these reactions efficiently. A broad scope of primary and secondary alcohols, including purely aliphatic examples, and 1,2-aminoalcohols can be methylated. Furthermore, alcohol methylation for the synthesis of pharmaceuticals has been demonstrated. The catalyst system tolerates many functional groups among them hydrogenation-sensitive examples and upscaling is easily achieved. Mechanistic investigations are indicative of a borrowing hydrogen or hydrogen autotransfer mechanism involving a bimetallic K-Mn catalyst. The catalyst accepts hydrogen as a proton and a hydride from alcohols efficiently and reacts with a chalcone via hydride transfer.

SUBMITTER: Schlagbauer M

PROVIDER: S-EPMC7003965 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Manganese-Catalyzed β-Methylation of Alcohols by Methanol.

Schlagbauer Martin M Kallmeier Fabian F Irrgang Torsten T Kempe Rhett R

Angewandte Chemie (International ed. in English) 20191212 4

We report an earth-abundant-metal-catalyzed double and single methylation of alcohols. A manganese catalyst, which operates at low catalyst loadings and short reaction times, mediates these reactions efficiently. A broad scope of primary and secondary alcohols, including purely aliphatic examples, and 1,2-aminoalcohols can be methylated. Furthermore, alcohol methylation for the synthesis of pharmaceuticals has been demonstrated. The catalyst system tolerates many functional groups among them hyd ...[more]

PMID: 31743576

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