Trityl chloride → Phenyl [1-methyl-5-(tritylamino)pyrazol-4-yl]carbamate

Participants

Reaction Steps

To a suspension of 5-amino-1-methyl-4-phenoxycarbonylaminopyrazole (153.8 g) in tetrahydrofuran (1 L) were added triethylamine (67 g) and triphenylmethyl chloride (185 g) at room temperature. The mixture was stirred for 6.5 hours. To the reaction mixture was added heptane (2.6 L) and the mixture was stirred for 1 hour. The precipitated solid was collected by filtration and washed with heptane-diisopropyl ether (1:1). The crude solid was suspended in water (3 L) and the suspension was stirred for 1 hour. The solid was collected by filtration and dried to give 1-methyl-4-phenoxycarbonylamino-5-triphenylmethylaminopyrazole (253.6 g).

Provenance & Evidence