p-Toluenesulfonic acid → [5-(3,4-Dichlorophenyl)-1-(4-methoxyphenyl)-1H-pyrazol-3-yl]methanol

Participants

Reaction Steps

A solution of p-toluenesulfonic acid (1.22 kg, 6.28 mol) in methanol (20.0 L) was added to the THF/EtOAc solution of 5-(3,4-dichlorophenyl)-1-(4-methoxyphenyl)-3-[[(tetrahydro-2H-pyran-2-yl)oxy]methyl]-1H-pyrazole (Example 515) at rt and the resulting mixture was stirred overnight (18 h). When HPLC analysis indicated the disappearance of the starting material, the reaction mixture was concentrated to remove methanol. The resulting mixture was washed with 10% aq. NaHCO3 (40.0 L) followed by brine (40.0 L). The organic layer was added to n-heptane and the resultant suspension was filtered, washed, and vacuum dried to afford [5-(3,4-dichlorophenyl)-1-(4-methoxyphenyl)-1H-pyrazol-3-yl]-methanol (4.65 kg, 63.7% over 3 chemical steps) as a solid. Data compared favorably with that obtained for Example 1, Step C.

Provenance & Evidence