Phosphorus trichloride → 2-Amino-5-(4-pyridyl)-4-[(4-piperonyl-1-piperazinyl)carbonyl]thiazole

Participants

Reaction Conditions

Reaction Steps

To a mixture of 1-piperonylpiperazine (2.72 g) and phosphorus trichloride (0.49 ml) in pyridine (20 ml) was added 2-amino-5-(4-pyridyl)-4-thiazolecarboxylic acid (1.24 g) and the mixture was stirred at 80° C. for 3 hours. The reaction mixture was evaporated in vacuo and the residue was dissolved in a mixture of ethyl acetate and water. The resultant mixture was adjusted to pH 8.0 with saturated aqueous potassium carbonate. The organic extract was dried over magnesium sulfate. The solvent was evaporated in vacuo to give a crystalline residue, which was recrystallized from ethyl acetate to afford 2-amino-5-(4-pyridyl)-4-[(4-piperonyl-1-piperazinyl)carbonyl]thiazole (0.45 g). mp 216°-217° C.

Provenance & Evidence