Synthesis and Spectral Characterization of Benzo[6,7] [1,5]diazocino[2,1-a]isoindol-12-(14H)-one Derivatives

A simple synthetic route to benzo[6,7][1,5]diazocino[2,1-a]isoindol-12(14H)-one ring system is developed from readily available starting materials 3-(2-oxo-2-phenylethyl) isobenzofuran-1(3H)-ones and 2-(aminomethyl)aniline catalysed by para-toluenesulfonic acid in toluene in 27-85% yields. The 1H- and 13C-NMR spectra of the final products were assigned using a variety of one and two-dimensional NMR experiments. The distinction between the two potential isomers of the final products was made on the basis of heteronuclear multiple bond connectivity NMR spectra (HMBC).