Reaction #88923

Reaction equation

Intermediate 54a

3-(5-Amino-3-tert-butyl-pyrazol-1-yl)-5-methyl-phenol

triethylamine

triisopropylsilyltrifluoromethanesulphonate

→

title compound

Yield 105.3%

5-tert-Butyl-2-(3-methyl-5-triisopropylsilanyloxy-phenyl)-2H-pyrazol-3-ylamine

Yield 105.3%

Solvents

DCM

DCM

Conditions

Workup

1. 1
   Washwashed with sat. sodium hydrogen carbonate solution
2. 2
   Dryingbrine, dried
3. 3
   Concentrationconcentrated in vacuo
4. 4
   OtherThe residue was purified by FCC

Procedure

To a solution of Intermediate 54a (430 mg, 1.75 mmol) in DCM (10 mL) and triethylamine (0.36 mL, 2.63 mmol) was added triisopropylsilyltrifluoromethanesulphonate (0.52 mL, 1.93 mmol). Mixture stirred for 1 h at RT, diluted with DCM, washed with sat. sodium hydrogen carbonate solution then brine, dried, and concentrated in vacuo. The residue was purified by FCC, using 0-25% EtOAc in cyclohexane, to give impure title compound (740 mg), contaminated with the ˜25% bis-silyl impurity. 1H NMR (300 MHz, CDCl3): inter alia 1.03-1.15 (18H, m), 1.18-1.35 (12H, m), 2.32 (3H, s), 3.74 (2H, br s), 5.49 (1H, s), 6.60-6.66 (1H, m), 6.85-6.89 (1H, m), 6.95-7.00 (1H, m).

Source