Imidazole → 5-tert-Butyl-2-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2H-pyrazol-3-ylamine

Participants

Reaction Steps

A solution of Intermediate 10a (1.00 g, 5.46 mmol), tert-butyl-dimethyl-chlorosilane (823 mg. 5.46 mmol), and imidazole (774 mg, 11.38 mmol) in DMF (9 mL) was stirred at RT under a nitrogen atmosphere for 18 h. Additional tert-butyl-dimethyl-chlorosilane (823 mg. 5.46 mmol) and imidazole (774 mg, 11.38 mmol) were added to the reaction mixture and stirred for 6 h. The reaction mixture was diluted with NH4Cl saturated aqueous solution (10 mL) and DCM (10 mL). The layers were separated and aqueous layer was extracted with DCM (3×10 mL). The combined organic layers were dried (MgSO4), filtered, concentrated in vacuo and purified by FCC, using 0-50% EtOAc in cyclohexane, to give the title compound (1.15 g, 70%). LCMS (Method 3): Rt 3.06, 3.23 min, m/z 298 [MH+].

Provenance & Evidence