Abnormal nucleophilic substitution of 3-trichloromethylpyridines by methoxide
作者:Ronald S. Dainter、Hans Suschitzky、Basil J. Wakefield、Nigel Hughes、Anthony J. Nelson
DOI:10.1016/s0040-4039(01)91414-5
日期:1984.1
3-Trichloromethylpyridine and its α-chlorinated derivatives behave as ambident electrophilic substrates towards methoxide which attacks an α-position and the trichloromethyl group.
METHOD FOR SEPARATING AND PURIFYING 2-CHLORO-3-TRIFLUOROMETHYLPYRIDINE
申请人:ISHIHARA SANGYO KAISHA, LTD.
公开号:US20200048202A1
公开(公告)日:2020-02-13
A method for separating and purifying 2-chloro-3-trifluoromethylpyridine useful as an intermediate for medicines, agrochemicals, and the like is provided.
The method includes:
1) in the process of producing chloro β-trifluoromethylpyridine compounds by allowing a β-methylpyridine compound to react with chlorine and hydrogen fluoride in a reaction apparatus, allowing a β-trifluoromethylpyridine compound to react with chlorine in a reaction apparatus, or allowing a chloro β-trichloromethylpyridine compound to react with hydrogen fluoride in a reaction apparatus,
2) fractionating a liquid mixture containing chloro β-trifluoromethylpyridine compounds from the reaction apparatus, and
3) separating and purifying 2-chloro-3-trifluoromethylpyridine from the liquid mixture.
2-Chloro-5-trichloromethylpyridine is obtained by chlorinating β-picoline in the vapor phase using a Mordenite zeolite or a supported palladium catalyst.