4-Piperidinecarboxylic acid → 2-(piperidin-4-yl)-1H-1,3-benzodiazole

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-piperidine carboxylic acid (5.30 g, 40 mmol), 1,2-diaminobenzene (4.32 g, 40 mmol) and polyphosphoric acid (40 g) were heated to 190° C. for 14 hours. Cooled, diluted with water (150 ml) and basified with 50% KOH to pH 8. Solution cooled in an ice/salt bath to give a precipitate which was collected by filtration and washed with water. Solid dried in vacuo to afford the title compound (8.0 g, 100%).

Provenance & Evidence