Ethyl Acetate → (E)-[2-(6-methoxycarbonyl-4-methyl-2-propylbenzimidazol-1-yl)methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene]acetonitrile

Participants

Reaction Steps

[step 1] 6-Methoxycarbonyl-4-methyl-2-propylbenzimidazole (EP502314; 1.19 g, 5.13 mmol) was dissolved in DMF (15 mL), potassium tert-butoxide (0.60 g, 5.3 mmol) was added at 0° C., and the mixture was stirred for 10 min. To this mixture was added a solution of (E)-(2-bromomethyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)acetonitrile obtained in Reference Example B1 in DMF (8 mL), and the mixture was stirred at room temperature for 2 hr. Ethyl acetate was added to the mixture, and the organic layer was washed with brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=3/1 tot/3) to give (E)-[2-(6-methoxycarbonyl-4-methyl-2-propylbenzimidazol-1-yl)methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene]acetonitrile (1.78 g, 73%).

Provenance & Evidence