2,6-Diethylaniline → 8-Amino-N-(2,6-diethylphenyl)-1-methyl-4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline-3-carboxamide

Participants

Reaction Conditions

Reaction Steps

Sodium hexamethyldisilazide (NaHMDS) in THF (1.0 M, 11.0 mL, 11.0 mmol) was added over 30 min to a solution of 2,6-diethylaniline (1.2 mL, 8.32 mmol) and ethyl 8-amino-1-methyl-4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline-3-carboxylate (0.760 g, 2.77 mmol) in THF (30 mL) at 0° C. The resulting brown solution was stirred at 0° C. for 10 min and allowed to warm to room temperature over a period of 30 min. After stirring at room temperature for 3 h, the reaction was quenched by the addiction of saturated acquesous NH4Cl (10 mL). The reaction was partitioned between ethyl acetate (50 mL) and water (50 mL). The acqueos layer was extracted with ethyl acetate (2×30 mL). The combined organic solution was washed with brine (50 mL), dried over Na2SO4, filtered and evaporated to dryness, the crude solid was purified by flash chromatography on silica gel (eluant: dichloromethane/methanol 95/5) to afford 0.830 g (80% yield) of the title compound.

Provenance & Evidence