Method for the preparation of 4-phenyl-1,3-benzodiazepins and precursors thereof
AssigneeHoechst-Roussel Pharmaceuticals Inc.
InventorsThomas B. K. Lee, George E. Lee
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Abstract
A compound of the formula ##STR1## is prepared by reacting an N-acylated-o-toluidine of the formula ##STR2## with n-alkyllithium to form a dilithio intermediate of the formula ##STR3## which can then be quenched with N-benzylidenemethylamine to form compound II. Hydrolysis of compound(II) yields the free base ##STR4## or its salt, which can be cyclized to form 4,5-dihydro-2,3-dimethyl-4-phenyl-3H-1,3-benzodiazepine or its physiologically acceptable salts, which are useful as pharmacological agents.
Claims10
A process for preparing N-[2-(2-methylamino-2-phenylethyl)phenyl]-2,2-dimethylpropanamide, wherein the process comprises reacting an N-acylated-o-toluidine of the formula ##STR11## with n-alkyllithium to provide a dilithio intermediate of the formula ##STR12## and quenching the dilithio intermediate with N-benzylidenemethylamine.
A process for preparing N-[2-(2-methylamine-2-phenylethyl)phenyl]-2,2-dimethylpropanamide, wherein the method comprises reacting N-[(2-methyl)phenyl]-2,2-dimethylpropanamide with n-butyllithium in solution in tetrahydrofuran and hexane and in a substantially anhydrous atmosphere at about -10.degree. C. to about 30.degree. C. for about 1 to about 2 hours to form a dilithio intermediate of the formula ##STR13## and quenching the dilithio intermediate with about 1 to about 2 molar equivalents of N-benzylidenemethylamine, based on the dilithio intermediate, at about 0.degree. C. to about 25.degree. C. for about 5 minutes to about 1 hour and in a substantially anhydrous atmosphere.
Dependencies are inferred from the claim text.