Reduction of Carboxylic Acids to Alcohols via Manganese(I) Catalyzed Hydrosilylation

• Published in: JACS Au Vol. 1; no. 6; pp. 742 - 749
• Main Authors: Antico, Emanuele, Schlichter, Peter, Werlé, Christophe, Leitner, Walter
• Format: Journal Article
• Language: English
• Published: American Chemical Society 28-06-2021
• Subjects: Letter
• ISSN: 2691-3704; 2691-3704
• DOI: 10.1021/jacsau.1c00140

The reduction of
carboxylic acids to the respective alcohols, in
mild conditions, was achieved using [MnBr(CO)
5
] as the
catalyst and bench stable PhSiH
3
as the reducing agent.
It was shown that the reaction with the earth-abundant metal catalyst
could be performed either with a catalyst loading as low as 0.5 mol
%, rare with the use of [MnBr(CO)
5
], or on a gram scale
employing only 1.5 equiv of PhSiH
3
, the lowest amount of
silane reported to date for this transformation. Kinetic data and
control experiments have provided initial insight into the mechanism
of the catalytic process, suggesting that it proceeds via the formation
of silyl ester intermediates and ligand dissociation to generate a
coordinatively unsaturated Mn(I) complex as the active species.