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Photocatalytic water splitting converts solar energy to storable hydrogen molecules which has the highest energy per mass. Most catalysts for photocatalytic water splitting utilize noble metals or precious metals. Organic photocatalysts are attracting more attention owing to several advantages like light weight, low cost, defined structure and tunability. In this study, the synthesis of several dibenzo[b,f][1,5]- diazocines via microwave irradiation for water splitting application is reported. Microwave irradiation facilitates fast, safe and simple synthesis in green reaction conditions. Mini library of dibenzo[b,f][1,5]diazocines were created in order to understand substituents effect on the photocatalytic activity.

Robinson′s synthesis has long been a classic in organic chemistry due to its simplicity and impact in the industry. Various modifications have been made to improve the system. Among them, replacing acetone with more acidic chemical equivalents such as calcium dicarboxylic acid or ethyl dicarboxylic acetone improved the yield. In line with this trend, our group previously reported the synthesis of mono- and di-N-substituted tropinone derivatives from the one-pot reaction of 2,5-dimethoxy tetrahydrofuran and various amines with acetonedicarboxylic acid in the presence of HCl and water at room temperature. In this study, the synthesis with acetone instead of acetone-dicarboxylic acid was examined. Mono- and di-N-substituted nortropinones were prepared in higher yields in all cases although there were extent to which yields increased depending on the nature of substituents

The main structure of many compounds containing spirohydantoin and Schiff bases of indenoquinoxalines and indenopyridopyrazinones expose valuable pharmacological properties. Herein, an effective synthesis and stereochemistry of indenoquinoxalinones (2a, 2b+bi~2d+di) and indenopyridopyrazinones (2e+ei~g+gi) via the reaction of ninhydrin with desirable diamines is reported. We synthesized the corres-ponding spirohydantoins (3a, 3b~d and 3bi~di) from synthesized indeno[1,2-b]quinoxalinones and indeno[1,2-b]pyrido[3,2-e]pyrazinones with the standard Bucherer-Bergs conditions (KCN, ammonium carbonate, acetonitrile, refluxing, without NaHSO3). And also synthesized the azomethine analogs (4~8+8i) of tetracyclic indeno[1,2-b]quinoxalinones as a Schiff base.

The report stated that the treatment of o-phenylenediamine with acetone dicarboxylic acid, acetone and acetophenone afforded 2,4,4-trimethyl-3H-5-hydro-1,5-benzodiazepine. However, direct reactions of o-phenylenediamine with oximes (acetone oxime, acetophenone oxime, and benzophenone oxime) as ketone equivalents did not occur. In the course of present investigations, it is found that dichloroamine-T can be an efficient reagent for the conversion of oximes into the corresponding carbonyl compounds. As a part of a research program related to the synthetic study of pharmacologically interesting benzodiazepine compounds, herein the synthesis of 1H-1,5-benzodiazepine derivatives from heteroaromatic ketones and acetone equivalents obtained using dichloroamine-T. On the other hand, when diamine (1,2-phenylene diamine or 1,2-naphthalene diamine) with heterocyclic ketone (acetyl pyridine or acetyl pyrazines) in the presenece of conc. HCl and SiO2 was refluxed, quinoxaline derivatives as yellow crystalline solids were isolated in high yields