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Title: Highly-chemoselective step-down reduction of carboxylic acids to aromatic hydrocarbons via palladium catalysis
Aryl carboxylic acids are among the most abundant substrates in chemical synthesis and represent a perfect example of a traceless directing group that is central to many processes in the preparation of pharmaceuticals, natural products and polymers. Herein, we describe a highly selective method for the direct step-down reduction of carboxylic acids to arenes, proceeding via well-defined Pd(0)/( ii ) catalytic cycle. The method shows a remarkably broad substrate scope, enabling to direct the classical acyl reduction towards selective decarbonylation by a redox-neutral mechanism. The utility of this reaction is highlighted in the direct defunctionalization of pharmaceuticals and natural products, and further emphasized in a range of traceless processes using removable carboxylic acids under mild, redox-neutral conditions orthogonal to protodecarboxylation. Extensive DFT computations were conducted to demonstrate preferred selectivity for the reversible oxidative addition and indicated that a versatile hydrogen atom transfer (HAT) pathway is operable.  more » « less
Award ID(s):
1650766
PAR ID:
10146146
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
10
Issue:
22
ISSN:
2041-6520
Page Range / eLocation ID:
5736 to 5742
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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