Benzoic Acid → 10-methoxy-5H-dibenz[b,f]azepine carboxamide

Reaction equation

[CH3:1][O:2][C:3]1[C:9]2[CH:10]=[CH:11][CH:12]=[CH:13][C:8]=2[NH:7][C:6]2[CH:14]=[CH:15][CH:16]=[CH:17][C:5]=2[CH:4]=1.C(O)(=O)C1C=CC=CC=1.[O-:27][C:28]#[N:29].[Na+]>C1(C)C=CC=CC=1>[CH3:1][O:2][C:3]1[C:9]2[CH:10]=[CH:11][CH:12]=[CH:13][C:8]=2[NH:7][C:6]2[CH:14]=[CH:15][CH:16]=[C:17]([C:28]([NH2:29])=[O:27])[C:5]=2[CH:4]=1

Participants

Procedure

An especially preferred method according to this invention comprises reaction of 10-methoxy-5H-dibenz[b,f]azepine with benzoic acid and sodium cyanate in toluene at reflux temperature to give 10-methoxy-5H-dibenz[b,f]azepine carboxamide as a major product (such as about 75%), along with 10-oxo-iminodibenzyl and other impurities. The reaction mixture is thereafter filtered and washed with water, and the toluene layer taken as such for hydrolysis in a biphasic system (aqueous hydrochloric acid/toluene) to furnish oxcarbazepine, which is purified just once (whereas twice at least is needed when the prior art process is carried out) in a mixture of methanol and dichloromethane (Scheme-5).