2-chloro-4-methylpyridine (2-chloro-4-picoline) reacts to palladium-catalyzed cross coupling reaction in the form of 3,5-bis(trifluoromethyl)phenylboronic acid in 2-(3,5-bis(trifluoromethyl)phenyl)phenyl)-4-methylpyridine.
In the assessment of gas-phase fundamentality of many fairly small organic molecules used in the chemicals, 2-chlor-4-picoline was used (2-chloro-4-methylpyridine).
- A process for the preparation of a 3-amino-2-chloro-4-alkylpyridine of the formula: wherein R is alkyl of from one to three carbon atoms, which comprises the steps of:
- a) reacting a compound of the formula: wherein R is as defined above and R1 is alkyl from one to three carbon atoms, with cyanoacetamide and a base, in the presence of an organic solvent, at a temperature of from 60°C to 80°C, for 1 to 4 hours, to produce a compound of the formula:
- b) reacting the compound produced in a) with a chlorinating agent, at a temperature of 110°C to 180°C, for 6 to 24 hours, to produce a compound of the formula:
- c) hydrogenating the compound produced in b) in the presence of an organic solvent, with an hydrogenation catalyst, at 344728.2 to 1034184.4 Pa (50 to 150 psi), at a temperature of from 20°C to 100°C, for 6 to 24 hours, to produce a compound of the formula:
- d) mixing the compound produced in c) with an ion exchange resin, at a temperature of 60°C to 100°C, for 1 to 4 hours, to produce a compound of the formula:
- e) reacting the compound produced in d) with a base and a halide, at a temperature of from 0°C to 85°C, for 1 to 4 hours, to produce a compound of the formula:
- f) contacting the compound produced in e) with chlorine gas, at a pH of 0.01 to 2, at a temperature of 5°C to 30°C for 0.5 to 2 hours, to produce the 3-amino-2-chloro-4-alkylpyridine of formula I.
- The process as described in Claim 1 where: I organic solvent (a) methanol or ethanol is the basis in (a) is KOH; (ii) chlorinating agent (b) is phenylphosphonic chloride or inorganic acid halide; (iii) organic solvent (c) contains methanol or THF and hydrogenating catalyst (c) contains either palladium chloride or palladium (v).
- An inorganic acid halide is reacted to a cycle, as recited in claim 2 whereas in (b) it is formed at 30°C to 50°C for 0.5 to 1 hour and hydrolyzed at a temperature of 0.5 to 1 hour.
- A process, as recited in Claim 3, wherein phosphorous oxychloride is the inorganic acid halide in b).
- A process as claimed in Claim 1, in which R is methyl.
- Process to prepare 3-amino-2-chloro-4-methylpyridine which consists of: a) reacting ethyl-acetoacetate with cyanoacetamide and base with organic solvent, to produce 3-cyano-2,6-dihydroxy-4-methyl-pyridine, at a temperature of 60 ° C to 80 ° C, for 1 to 4 hours; b) reacting with a three-cyano-2,6-dihydroxy-4-methyl-pyridine, generated in a),
- Phase as demanded from Claim 6 in which: I the organic solvent in (a) consists of methanol or ethanol and (a) the chlorinating agent is KOH; (ii) phenylphosphonic chloride or inorganic acid halide is the chlorine agent in (b) the organic solvent in (c) is methanol or THF and (c) hydrogenation catalyst is palladium chloride and palladium metal.
- A procedure, as set out in claim 7, is reacted with an inorganic half-acid by means of a) compound formed in b, and any excess inorganic halide is then hydrolyzed for 0.5 to 1 hour at a temperature from 30 to 50°C.
- A process recited in Claim 8 in which phosphorous oxychloride is inorganic halide in b). Apart from this 4,4′-Bipyridyl is also manufactured in the same process.