2-Methyl-2-butene → 1-Ethyl-3-propyl-4-[[2'-[[(trifluoromethyl)sulphonyl]amino][1,1'-biphenyl]-4-yl]methyl]-1H-pyrazole-5-carboxylic acid

Participants

Reaction Steps

A solution of sodium chlorite (0.4 g) and sodium dihydrogen orthophosphate (2.56 g) in water (5 ml) was added to a solution of the product of Example 88 (430 mg) and 2-methyl-2-butene (4.5 ml, 2M solution in THF) in t-butanol (5 ml) and THF (10 ml) and the resulting mixture stirred for 3 h. Solvent was removed in vacuo, the residue taken up in dichloromethane (10 ml) and washed with water (10 ml). 2N Sodium hydroxide (10 ml) was added to the organic solution and the organic layer removed. 2N Hydrochloric acid (~11 ml) was added to the aqueous phase which was then extracted with ethyl acetate (2×15 ml). The dried organic extracts were evaporated in vacuo to give a yellow gummy solid which was recrystaltised from System D (1:1) to give the title compound as a white solid (250 mg) m.p. 68°-72° C.

Provenance & Evidence