Increased intensity of tert -butoxyl radical emission in 4-chloro-2-methylphenoxyacetic acid (MCPA) synthesis
✍ Scribed by Jezierski, Adam; Zakrzewski, Jerzy; Moszczyński, Wiesław
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 86 KB
- Volume
- 55
- Category
- Article
- ISSN
- 1526-498X
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✦ Synopsis
The important herbicide, 2-methyl-4-chlorophenoxyacetic acid (MCPA) was synthesized by the chlorination of 2-methylphenoxyacetic acid with tert-butyl hypochlorite in the presence of methyl N,N-dimethylglycinate as a catalyst, giving a high yield and regioselectivity. The reaction was investigated using the spin-trapping technique in electron paramagnetic resonance measurement conditions, with nitrosodurene as a spin trap. Increased intensity emission of the tert-butoxyl radical (2.9 times in relation to the starting level) was observed after the catalyst had been introduced into the reaction mixture, indicating a free radical mechanism for the reaction.