Methyl Isobutyl Ketone → 5-chloro-1-{1-[3-(2-oxo-3(2H)-benzoxazolyl)propyl]-4-piperidinyl}-1,3-dihydro-2H-benzimidazol-2-one

Beteiligte Stoffe

Reaktionsschritte

A mixture of 4.7 parts of 3-(3-chloropropyl)-2(3H)-benzoxazolone, 5 parts of 5-chloro-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one, 6.4 parts of sodium carbonate and 200 parts of 4-methyl-2-pentanone is stirred and refluxed overnight with water-separator. After cooling, water is added and the layers are separated. The 4-methyl-2-pentanone phase is dried, filtered and evaporated. The residue is boiled in a mixture of 4-methyl-2-pentanone, 2-propanol and methanol. The whole is cooled and the product is filtered off and dried, yielding 4 parts (47%) of 5-chloro-1-{1-[3-(2-oxo-3(2H)-benzoxazolyl)propyl]-4-piperidinyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 212.3° C.

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