Synthesis of novel benzo naphtho naphthyridines from 2,4-dicloroquinolines

Abstract

A schematic study on the condensation of 2,4-dichloroquinolines (1) with 1-naphthyamine (2) in the presence of CuI as a catalyst to functionalized mono (3) and di (4) substituted naphthylamino quinolines was described. Consequently, these mono- and di-substituted amines on polyphosphoric acid-catalyzed cyclization reaction with p-toluic acid and acetic acid to yield the linear benzo[b]naphtho[2,1-g][1,8]naphthyridines (5) and angular benzo[b]naphtho[2,1-h] naphthyridines (6) in good yields. In addition to descried the similar synthesis of benzo[g]naphtho [2,1-b][1,8]naphthyridines (12) and benzo[h]naphtho[2,1-g][1,8]naphthyridines (13) from 2,4-dichlorobenzo[h]quinoline (8) with various anilines (9) through my intermediates (10 and 11).