Reaction #2254181

Reaction equation

5-(hydroxyimino-methyl)-3-methyl-thiophene-2-carboxylic acid (2,2,2-trifluoro-ethyl)-amide

1,3-dichloro-5-(1-trifluoromethyl-vinyl)-benzene

Chlorox

NaOH

→

5-[5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-3-methyl-thiophene-2-carboxylic acid (2,2,2-trifluoro-ethyl)-amide

Yield 15.7%

Solvents

THF

diethyl ether

Conditions

Workup

1. 1
   OtherThe cold bath is then removed
2. 2
   workup.ADDITIONwater is added
3. 3
   Extractionthe reaction mixture is extracted three times with ethyl acetate
4. 4
   Dryingdried over Na2SO4
5. 5
   Concentrationconcentrated in vacuo
6. 6
   OtherThe crude product is purified on a semi-preparative HPLC

Procedure

Chlorox (4%, 1.02 nil) and NaOH (1N, 0.1 ml) are premixed and then added to a solution of 5-(hydroxyimino-methyl)-3-methyl-thiophene-2-carboxylic acid (2,2,2-trifluoro-ethyl)-amide (200 mg) and 1,3-dichloro-5-(1-trifluoromethyl-vinyl)-benzene (170 mg, example 1, Step A) in THF (3 ml) and diethyl ether (3 ml) at 5° C. The cold bath is then removed. After 21 hours, water is added and the reaction mixture is extracted three times with ethyl acetate. The organic phases are combined, dried over Na2SO4 and concentrated in vacuo. The crude product is purified on a semi-preparative HPLC to yield 5-[5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-3-methyl-thiophene-2-carboxylic acid (2,2,2-trifluoro-ethyl)-amide (56 mg) as light yellow oil. MS (HPLC/MS): 505 (MH+). Retention time: 4.38 min.

Source