Synthesis of Novel Tetrahydrospiro[1,4]diazepine

Green synthesis of tetrahydrospiro[1,4]diazepine has been reported in EtOH/H2O (1:1) in thepresence of p-TSA as catalyst.Spirooxindoles are classified as important structural motifs dueto their distribution in diverse natural products, biologically and pharmaceutical activitiessuch as the influenza virus, as inhibitors of the virus and anti-cancer agents [1]. Therefore, weconducted a series of examination the chemistry of 5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolone-1,2-dione, in which the reactivity of the ketone carbonyl group of the 2-ketoamideunit was utilized. Thus, we were able to construct various spiro [3,3’-oxindoles] viathree and four component combination [2-4]. Amongst, spirouracil-1,4-dihydropyridine moietieshave shown important biological and medicinal activities. As a part of our ongoing interestin this context, we reported a simple and facile synthesis of a new type tetrahydrospiro[1,4]diazepine (3) in the presence of p-TSA as catalyst (Figure 1) by reaction of (E)-1-(2-oxo-2-phenylethylidene)-5,6-dihydro-1H-pyrrolo[3,2,1-ij]quinolin-2(4H)-one (1), 1,2-diaminophenyl derivatives (2) in environmentally friendly solvent, EtOH/H2O.