Synlett 2022; 33(16): 1670-1674
DOI: 10.1055/a-1887-7885
letter

Aerobic Photooxidation of Toluene Derivatives into Carboxylic Acids with Bromine–Water under Catalyst-Free Conditions

a   Department of Materials and Life Science, Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi, Shizuoka 437-8555, Japan
,
Yugo Sakamoto
a   Department of Materials and Life Science, Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi, Shizuoka 437-8555, Japan
,
Sho Yamahara
a   Department of Materials and Life Science, Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi, Shizuoka 437-8555, Japan
,
Atsuhito Kitajima
a   Department of Materials and Life Science, Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi, Shizuoka 437-8555, Japan
,
Naoki Kugisaki
b   Research and Development Department, Iharanikkei Chemical Industry Co. Ltd., 5700-1 Kambara, Shimizu-ku, Shizuoka 421-3203, Japan
,
b   Research and Development Department, Iharanikkei Chemical Industry Co. Ltd., 5700-1 Kambara, Shimizu-ku, Shizuoka 421-3203, Japan
› Author Affiliations


Abstract

The photoirradiation of toluene derivatives with two equivalents of bromine in benzotrifluoride–water provided a satisfactory yield of the corresponding benzoic acid derivatives. Either a fluorescent lamp, blue LED (454 nm), or UV LED (385 nm) was used for the photoreaction. The reaction pathway might proceed through the dibromination of benzylic carbon, generation of the benzylic radical via oxidative C–H abstraction, formation of benzoyl bromide, and hydrolysis of carboxylic acid.

Supporting Information



Publication History

Received: 27 May 2022

Accepted after revision: 29 June 2022

Accepted Manuscript online:
29 June 2022

Article published online:
26 July 2022

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