Hydrochloric Acid → (Z)-2-(2-hydroxymethyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)propiononitrile

Participants

Reaction Conditions

Reaction Steps

[step 2] To a solution of sodium hydride (60%, 0.856 g, 21.4 mmol) and diethyl 1-cyanoethylphosphonate (4.09 g, 21.4 mmol) in DMF (35 mL) was added a solution of ethyl 10,11-dihydro-5-oxo-5H-dibenzo[a,d]cycloheptene-2-carboxylate (3.0 g, 10.7 mmol) obtained in step 1 in DMF (10 mL) under ice-cooling, and the mixture was stirred at 80° C. for 3 hr. Water was added to the mixture, and the mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to give a residue. The obtained residue was dissolved in THF (50 mL), lithium borohydride (1.11 g, 50.9 mmol) was added, and the mixture was stirred at 50° C. for 5 hr. The mixture was neutralized with 2 mol/L hydrochloric acid, and extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform/ethyl acetate=98/2) to give (E)-2-(2-hydroxymethyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)propiononitrile (0.730 g, 27%) and (Z)-2-(2-hydroxymethyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)propiononitrile (0.728 g, 27%).

Provenance & Evidence