Triethylamine → 2-Chloro-3-(trifluoromethyl)pyridine

HRID 2403642Notes

Reaction equation

HRID 2403642 reaction equation
[Cl:1][C:2]1[C:7]([C:8]([F:11])([F:10])[F:9])=[CH:6][C:5](I)=[CH:4][N:3]=1.C1(P(C2C=CC=CC=2)C2C=CC3C(=CC=CC=3)C=2C2C3C(=CC=CC=3)C=CC=2P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C(N(CC)CC)C.C(=O)([O-])[O-].[Cs+].[Cs+]>C1(C)C=CC=CC=1.C([O-])(=O)C.[Pd+2].C([O-])(=O)C>[Cl:1][C:2]1[C:7]([C:8]([F:9])([F:10])[F:11])=[CH:6][CH:5]=[CH:4][N:3]=1

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 10796Cesium carbonateHCID 634876Binap, (A+-)-HCID 115005132-Chloro-5-iodo-3-(trifluoromethyl)pyridine

Product 1

HCID 5898332-Chloro-3-(trifluoromethyl)pyridineYield 40%

Reagents, catalysts & solvents 2

HCID 167845palladium(II) acetateCatalystHCID 1140TolueneSolvent

Procedure

A solution of 2-hydroxy-3-(trifluoromethyl)pyridine C in a mixture of N-iodosuccinimide (NIS), acetonitrile, and dimethylformamide (DMF) is heated at 80° C. for 2 hours to produce 2-hydroxy-3-trifluoromethyl-5-(iodo)pyridine I (greater than 80% yield). The 2-hydroxy-3-trifluoromethyl-5-(iodo)pyridine I is then mixed with POCl3 in DMF and heated to 130° C. in a microwave for 20 minutes to produce 2-chloro-3-trifluoromethyl-5-(iodo)pyridine J (yield of 50 to 55%). The 2-chloro-3-trifluoromethyl-5-(iodo)pyridine K is reacted in a solution of pMBnNH2, palladium(II)acetate, 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP), triethylamine, and cesium carbonate in toluene to produce 5-((4-methoxyphenyl))methylamino)-2-chloro-3-(trifluoromethyl)pyridine K (yield of 40%). The 5-((4-methoxyphenyl))methylamino)-2-chloro-3-(trifluoromethyl)pyridine K is reacted in a solution of zinc cyanide, tris(dibenzylideneacetone)dipalladium (Pd2(dba)3), and 1,1′-bis(diphenylphosphino)ferrocene (dppf) in DMF to provide 5-(4-methoxybenzylamine)-2-cyano-3-(trifluoromethyl)pyridine K (yield of 92%). The 5-(4-methoxybenzylamine)-2-cyano-3-(trifluoromethyl)pyridine K is reacted in a solution of dichloromethane and trifluoroacetic acid to provide 2-cyano-3-trifluoromethyl-5-(amino)pyridine H (yield greater than 95%). The 2-cyano-3-trifluoromethyl-5-(amino)pyridine H is reacted with thiophosgene in water at 25° C. for 2 hours to provide 5-isothiocyanato-3-(trifluoromethyl)pyridine-2-carbonitrile A (yield of 74% to 95%).

Sources & evidence

ORD record
ord-a55650a136864398ac78060bf0e47d7b
Source dataset
uspto-grants-2014_08
Patent number
US08802689B2

Reaction notes

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