Benzotriazole chemistry and the Friedel-Crafts reaction are combined in a new synthesis for phenanthridine and its tosyl derivative 5-ptoluenesulfonyl-5,6-dihydrophenanthridine. A two step synthesis is devised for phenanthridine, the first step being a benzotriazolyl substitution reaction in which the benzotriazolyl moiety is introduced into the structure of a primary aromatic amine. The second step involves cyclisation of the amine via elimination of a benzotriazolyl moiety using concentrated sulfuric acid as a Friedel-Crafts catalyst. 5-ptoluenesulfonyl-5,6-dihydrophenanthridine is synthesised by a one pot method using aluminium chloride as a Friedel-Crafts catalyst. Benzotriazole and Friedel-Crafts strategies have also been applied in a two step synthesis for N(benzotriazol-1-ylmethyl)-1,2,3,4- tetrahydroisoquinoline, however favourable conditions could not be developed to successfully complete the synthesis.
|Date of Award
|Naseem H. Peerzada (Supervisor)