Ethyl bromoacetate → Ethyl (5,6-dihydro-4H-dibenzo[de,h]quinol-7-yloxy)acetate

Participants

Reaction Conditions

Reaction Steps

7-Hydroxy-5,6-dihydro-4H-dibenzo[de,h]quinoline (27 g) [prepared as described in Example 2] is added to a suspension of sodium hydride (50% dispersion in mineral oil; (5.75 g) in anhydrous dimethylformamide (520 cc) and then, after stirring for 4 hours, ethyl bromoacetate (21.3 g) in solution in anhydrous dimethylformamide (20 cc) is added. The reaction mixture is maintained for 22 and a half hours at about 20° C., is distilled water (10 cc) is added, the mixture is concentrated to a volume of 400 cc, distilled water (4600 cc) is added and the mixture is extracted eight times with diethyl ether (total 3500 cc). The combined organic solutions are washed four times with distilled water (total 4000 cc), dried over anhydrous sodium sulphate, treated with decolourising charcoal (5 g), filtered and evaporated to dryness. The residue is dried by azeotropic distillation with methylene chloride (150 cc) and then crystallised from ethanol (16 cc). After cooling for 21 hours at about 5° C., the resulting crystals are filtered off, washed twice with ethanol (total 18 cc), which has been cooled to -20° C., and dried under reduced pressure (20 mm Hg) at 20° C. Ethyl (5,6-dihydro-4H-dibenzo[de,h]quinol-7-yloxy)acetate (16.95 g), melting at 70° C., is thus obtained.

Provenance & Evidence