1,1'-Thiocarbonyldiimidazole → tert-Butyl 4-carbamothioylpiperazine-1-carboxylate

Participants

Reaction Steps

To a solution of piperazine-1-carboxylic acid tert-butyl ester (32.2 mmol) in tetrahydrofuran (60 ml) was added thiocarbonyldiimidazole (37.0 mmol). The reaction was stirred at RT for 2 h then heated at 55° C. for 1 h. The reaction was concentrated in vacuo to approximately half the volume and methanolic ammonia added (7N, 107.4 mmol). The reaction was heated at 55° C. for 16 h. The reaction was concentrated in vacuo to approximately half the volume and cooled to 0° C. at which point the product precipitated from solution. The product was collected by filtration to yield the title compound as a white solid (3.3 g). 1H NMR (400 MHz, d6-DMSO) 1.40 (9H, s), 3.32 (4H, s), 3.71 (4H, s), 7.42 (1H,s).

Provenance & Evidence