Potassium Iodide → 5-bromo-1-{1-[4,4-bis(4-fluorophenyl)butyl]-4-piperidinyl}-1,3-dihydro-2H-benzimidazol-2-one

Participants

Reaction Steps

A mixture of 7 parts of 1-chloro-4,4-bis(4-fluorophenyl)-butane, 5.9 parts of 5-bromo-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one, 6.4 parts of sodium carbonate, 0.2 parts of potassium iodide and 200 parts of 4-methyl-2-pentanone is stirred and refluxed overnight. The reaction mixture is cooled, water is added and the layers are separated. The organic phase is dried, filtered and evaporated. The residue is crystallized twice: first from a mixture of 2-propanol and 2,2'-oxybispropane and then from ethanol. The product is filtered off and dried, yielding 5-bromo-1-{1-[4,4-bis(4-fluorophenyl)butyl]-4-piperidinyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 182° C.

Provenance & Evidence