Diisopropylethylamine → 4-chloro-1,3-dimethyl-N-[(4R)-2-phenylimidazo[1,2-a]pyrimidin-7-yl]-1H-pyrazole-5-carboxamide

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Reaction Conditions

Reaction Steps

4-Chloro-2,5-dimethyl-2H-pyrazole-3-carboxylic acid (100 mg, 0.57 mmol) and diisopropylethylamine (369 mg, 2.86 mmol) were added to a solution of 2-phenyl-imidazo[1,2-a]pyrimidin-7-ylamine (example 1, step 1, 100 mg, 0.48 mmol) in ethyl acetate (3 ml). At 0° C., propylphosphonic acid anhydride (1-propanephosphonic acid cyclic anhydride, 50% in ethyl acetate, 0.7 ml, 2.5 eq.) was added dropwise to the mixture. After stirring for 30 min at 0° C., the mixture was stirred overnight at RT. The mixture was taken up in ethyl acetate, washed (water), dried (Na2SO4), and concentrated under reduced pressure. The title compound (16 mg, 9%) was obtained from the residue by preparative HPLC (254 nm, Agilent Zorbax XdB-C18, Run: 7 min, Flow: 30 ml/min, Gradient: 0.0 min: 95/5 H2O/CH3CN; 0.5 min: 95/5 H2O/CH3CN 4.5 min: 5/95 H2O/CH3CN; 6.9 min 5/95 H2O/CH3CN; 7 min 95/5 H2O/CH3CN).

Provenance & Evidence