Diisopropylethylamine → 2-(3-Benzyloxy-phenyl)-5-[2-(tert-butyl-diphenyl-silanyloxy)-1,1-dimethyl-ethyl]-2H-pyrazol-3-ylamine

Participants

Reaction Steps

A solution of Intermediate 153b (1.00 g, 2.63 mmol) in ethanol (IMS grade, 20 mL) was treated with 3-benzyloxyphenylhydrazine hydrochloride (0.66 mL, 2.63 mmol) then DIPEA (0.46 mL, 2.63 mmol) and the mixture was heated to reflux for 114 h. The cooled reaction mixture was diluted with EtOAc and a saturated aqueous sodium bicarbonate solution and the mixture was filtered and the phases separated. The aqueous layer was extracted with EtOAc (×2) and the combined organic phase was washed with brine, dried (Na2SO4), and concentrated in vacuo to give an orange oil (1.62 g). The gum was purified by FCC, using 0-20% EtOAc in cyclohexane, to give the title compound as a yellow oil (1.21 g, 80%). LCMS (Method 3): Rt 5.40 min, m/z 576.5 [MH+].

Provenance & Evidence