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

HRID 884892Notes

Reaction equation

HRID 884892 reaction equation
[Cl:1][C:2]1[C:7]([C:8]([F:11])([F:10])[F:9])=[CH:6][C:5]([NH:12][C:13](=O)[C:14]2[CH:19]=[CH:18][N:17]=[CH:16][CH:15]=2)=[C:4]([OH:21])[CH:3]=1.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:1][C:2]1[C:7]([C:8]([F:9])([F:10])[F:11])=[CH:6][C:5]2[N:12]=[C:13]([C:14]3[CH:15]=[CH:16][N:17]=[CH:18][CH:19]=3)[O:21][C:4]=2[CH:3]=1

Participants

6

Reactant 4

HCID 8028TetrahydrofuranHCID 11776TriphenylphosphineHCID 220568ethyl N-ethoxycarbonyliminocarbamateHCID 66880038N-[4-chloro-2-hydroxy-5-trifluoromethylphenyl]isonicotinamide

Product 1

HCID 668817606-Chloro-2-(pyridin-4-yl)-5-(trifluoromethyl)benzoxazoleYield 69.3%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

To a mixture of 1.01 g of N-[4-chloro-2-hydroxy-5-(trifluoromethyl)phenyl]isonicotinamide, 10 ml of tetrahydrofuran and 0.92 g of triphenylphosphine, 1.53 g of 40% toluene solution of diethyl azodicarboxylate was added dropwise at room temperature, and the reaction mixture was stirred for two hours. The reaction mixture was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography and the resultant crystals washed with methanol to give 0.66 g of 6-chloro-2-(pyridin-4-yl)-5-(trifluoromethyl)benzoxazole (hereinafter, referred to as “active compound 80”).

Workup

  1. additionwas added dropwise at room temperature
  2. concentrationThe reaction mixture was concentrated under reduced pressure
  3. washthe resultant crystals washed with methanol

Sources & evidence

ORD record
ord-a02e72fd48a342eeafddb251076bfa91
Source dataset
uspto-grants-2012_08
Patent number
US08242133B2

Reaction notes

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