Pyrazole → [3-(1H-Pyrazol-1-yl)phenyl]acetic acid

Participants

Reaction Steps

Pyrazole (1.2 eq), Cs2CO3 (2.5 eq), CuI (0.5 eq), trans-1,2-cyclohexanediamine (0.6 eq) and dodecane (1 eq), were added to a stirred solution of 3-bromophenylacetic acid (1 eq) in dioxane at room temperature under an inert atmosphere. The mixture was irradiated in a microwave reactor (PersonalChemistry Emrys™ Optimiser, 300 W, 160° C., 20 min), then added to a 1N aqueous solution of NaOH, and extracted with Et2O. The aqueous phase was acidified to pH=3 with HCl 2N, then extracted with ethyl acetate; this phase was washed with brine, dried over Na2SO4 and the solvent was removed under reduced pressure. The crude material was purified on SPE cartridge (Silica) eluting with a gradient from Cyclohexane/ethyl acetate 8:2, to Cyclohexane/ethyl acetate 1:1, affording the title compound in 65% yield.

Provenance & Evidence