Ethyl Acetate → tert-butyl {2-[(2-{[1-methyl-5-(tritylamino)-1H-pyrazol-4-yl]amino)-2-oxoacetyl)amino]ethyl}carbamate

Participants

Reaction Steps

To a solution of 1,1′-(1,2-dioxo-1,2-ethanediyl)bis-1H-imidazole (761 mg) in N,N-dimethylformamide (8 ml) was added 1-methyl-N5-trityl-1H-pyrazole-4,5-diamine (709 mg) under ice-cooling, and the mixture was stirred at room temperature for 30 minutes. To the reaction mixture was added a solution of tert-butyl 2-aminoethylcarbamate (1.28 g) in N,N-dimethylformamide (2 ml), and the mixture was stirred at room temperature for 27 hours. To the reaction mixture was added ethyl acetate (50 ml). After the precipitate was filtered off, the filtrate was washed successively with water, 5% aqueous citric acid solution and brine. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The crystalline residue was washed with a mixed solvent of diethyl ether and ethyl acetate and dried in vacuo to give tert-butyl {2-[(2-{[1-methyl-5-(tritylamino)-1H-pyrazol-4-yl]amino}-2-oxoacetyl)amino]ethyl}carbamate (823 mg) as a solid.

Provenance & Evidence