Tetrahydrofuran → 6-Chloro-2-(3-fluoropyridin-4-yl)-5-(trifluoromethyl)benzoxazole

HRID 884902Notes

Reaction equation

HRID 884902 reaction equation
[F:1][C:2]1[CH:22]=[N:21][CH:20]=[CH:19][C:3]=1[C:4]([NH:6][C:7]1[CH:12]=[C:11]([C:13]([F:16])([F:15])[F:14])[C:10]([Cl:17])=[CH:9][C:8]=1[OH:18])=O.O1CCCC1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N(C(OCC)=O)=NC(OCC)=O>C1(C)C=CC=CC=1>[Cl:17][C:10]1[C:11]([C:13]([F:16])([F:15])[F:14])=[CH:12][C:7]2[N:6]=[C:4]([C:3]3[CH:19]=[CH:20][N:21]=[CH:22][C:2]=3[F:1])[O:18][C:8]=2[CH:9]=1

Participants

6

Reactant 4

HCID 8028TetrahydrofuranHCID 11776TriphenylphosphineHCID 220568ethyl N-ethoxycarbonyliminocarbamateHCID 668800483-fluoro-N-[4-chloro-2-hydroxy-5-trifluoromethylphenyl]isonicotinamide

Product 1

HCID 668801106-Chloro-2-(3-fluoropyridin-4-yl)-5-(trifluoromethyl)benzoxazoleYield 88.4%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

To a mixture of 2.08 g of 3-fluoro-N-[4-chloro-2-hydroxy-5-(trifluoromethyl)phenyl]isonicotinamide, 13 ml of tetrahydrofuran and 1.79 g of triphenylphosphine, 2.98 g of 40% toluene solution of diethyl azodicarboxylate was added dropwise at room temperature. The reaction mixture was stirred for one hour. The reaction mixture was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography to give 1.74 g of 6-chloro-2-(3-fluoropyridin-4-yl)-5-(trifluoromethyl)benzoxazole (hereinafter, referred to as “active compound 90”).

Workup

  1. additionwas added dropwise at room temperature
  2. concentrationThe reaction mixture was concentrated under reduced pressure

Sources & evidence

ORD record
ord-976582d5f2ba4ce791cc18f33ca77fc7
Source dataset
uspto-grants-2012_08
Patent number
US08242133B2

Reaction notes

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