Potassium Carbonate → But-2-ynyl 4-[4-[(3aS,7aS)-2-oxo-3a,4,5,6,7,7a-hexahydro-3H-benzimidazol-1-yl]-1-piperidyl]-4-methyl-piperidine-1-carboxylate

Participants

Reaction Steps

To a solution of (3aS,7aS)-3-[1-(4-methyl-4-piperidyl)-4-piperidyl]-3a,4,5,6,7,7a-hexahydro-1H-benzimidazol-2-one (HCl salt, 0.4105 g, 1.15 mmol) and potassium carbonate (0.170 g, 1.23 mmol) in water (3.00 mL) was added a solution of but-2-ynyl chloroformate (0.156 mL, 1.38 mmol) in dichloromethane (3 mL). The reaction mixture was stirred at room temperature overnight. The mixture was poured into hydrometrix varian column chem elut catridge column and rinsed with dichloromethane (3 Column volumes). Concentrated in vacuo and the residue was purified by flash chromatography (0 to 50% MeOH/Ethyl acetate) and followed by preparative LC/MS (high pH) to give the title compound (0.036 g, 7.59%). 1H NMR (400 MHz, CHLOROFORM-D) δ ppm 1H NMR (400 MHz, CDCl3) δ ppm 1.30-1.47 (m, 6H), 1.49 (s, 2H), 1.62-1.76 (m, 1H), 1.76-2.00 (m, 9H), 2.34 (s, 2H), 2.72-2.98 (m, 6H), 2.99-3.09 (m, 2H), 3.49-3.85 (m, 2H), 4.11 (s, 1H), 4.27 (s, 2H), 4.49 (s, 1H), 4.61-4.72 (m, 2H) MS (M+1): 417.3.

Provenance & Evidence