Patent US834175A successfully refreshed from Google Patents.
Patent EP0013474A2 successfully refreshed from Google Patents.
EP0013474A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Preparation of 2-chloro-5-trifluoromethylpyridine
Assignee: Syngenta Ltd
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Filing: 1979-11-07
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Granted: —
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Expires: 1999-11-07
Abstract
Abstract 2-chloro-5- trifluoromethylpyridine or a 2-chloro-5- perchlorofluoromethylpyridine is prepared by chlorination of 3-trifluoromethylpyridine or a 3-perchlorofluoromethylpyridine respectively.
Inventors
- 👤 Norman Leyland Roberts
- 👤 Graham Whittaker
- 👤 Anne O'brien
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 18:35
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/61
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
75 words
A process for the preparation of 2-chloro-5-trifluoromethylpyridine or a 2-chloro-5-perchlorofluoromethylpyridine characterised in that 3-trifluoromethyipyridine or a 3- perchlorofluoromethylpyridine respectively is chlorinated:- (i) in the vapour phase at a temperature in the range from 100°C to 500°C, provided that when the temperature is below 250°C the chlorination is carried out in the presence of ultra-violet radiation, or (ii) in the liquid phase in the presence of ultra-violet radiation and/or in the presence of a free-radical initiator.
Claim 2
Dependent Claim
75 words
A process for the preparation of 2-chloro-5-trifluoromethylpyridine or a 2-chloro-5-perchlorofluoromethylpyridine characterised in that 3-trifluoromethyipyridine or a 3- perchlorofluoromethylpyridine respectively is chlorinated:- (i) in the vapour phase at a temperature in the range from 100°C to 500°C, provided that when the temperature is below 250°C the chlorination is carried out in the presence of ultra-violet radiation, or (ii) in the liquid phase in the presence of ultra-violet radiation and/or in the presence of a free-radical initiator.
Claim 3
Dependent Claim
28 words
A process according to Claim 1 characterised in that the reaction is carried out in the vapour phase at a temperature in the range from 300°C to 450°C.
Claim 4
Dependent Claim
25 words
A process according to Claim 2 characterised in that the proportion of chlorine employed is at least 1 mole per mole of 3-trifluoromethylpyridine or 3-perchlorofluoromethylpyridine.
Claim 5
Dependent Claim
26 words
A process according to Claim 3 characterised in that the proportion of chlorine employed is from 1 to 6 moles per mole of 3-trifluoromethylpyridine or 3-perchlorofluoromethylpyridine.
Claim 6
Dependent Claim
20 words
A process according to any of Claims 2 to 4 characterised in that the reaction mixture contains an organic diluent.
Claim 7
Dependent Claim
14 words
A process according to Claim 5 characterised in that the diluent is carbon tetrachloride.
Claim 8
Dependent Claim
28 words
A process according to Claim 1 characterised in that the voaction is carried out in the liquid phase at a temperature in the range from 0°C to 100°C.
References Cited (Backward Citations)
No citation records indexed.
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