Study On Highly Atom-Efficient Synthesis Of Several Tpyes Of Novel Benzazepine Compounds

Owing to possess some unique biological and pharmaceutical activities,benzazepine compounds have attracted people’s considerable attention, and their basic structural units widely distribute in pharmaceuticals, agrochemicals and functional materials, hence benzazepine compounds constitute the basic starting materials or the key intermediates for the preparation of these important products. Concerning some key issues of the existing synthetic methods, the development of efficient, green, facile and atom-economical synthetic methods to construct benzazepine compounds is one of the most important research tasks in synthetic organic field. The research work of this thesis has emphasized on the development of several operation-simple, highly atom economic and broad substrate scope methods for the synthesis of benzazepine compounds, which has provided facile and efficient synthetic routes to access some pharmaceutical intermediates and bioactive substances.Initially, by using phosphotungstic acid(PTA) as a reusable catalyst, a convenient synthesis of novel heteroatom substituted quinolines from 2-aminoaryl ketones and α-heteroatom bearing ketones has been demonstrated via Friedl?nder annulation. The transformation has the advantages of operational simplicity, wide substrate scope, solvent-free conditions and catalyst recyclability, making it a practical protocol for the preparation of heteroatom substituted quinoline productsSecondly, by employing Ru3(CO)12/Binap/t-Bu OK as an efficient catalyst system, the N-alkylation of 2-aminobenzonitriles using pyridyl methanols as the alkylating reagents has been firstly demonstrated. The synthetic protocol can be applied to synthesize a wide range of 2-N-pyridylmethyl benzonitriles in moderate to good yields upon isolation. Notably, the 2-N-pyridylmethylated benzonitriles might serve as potential ligands for the preparation of N^N^N pincer organometallic complexes or materials, and the applications in transition-metal catalysis. Through an exploration of its synthetic utility, we have demonstrated novel straightforward synthesis of biologically interesting 1,2,3,4-tetrahydrobenzo[e][1,4]diazepin-5-ones, providing an important basis for discovering new bio-active compounds.Finally, via a tandem nucleophilic addition, dehydrogenation of alcohols and intramolecular imination sequences, we have demonstrated a new method for convenient synthesis of 2-arylquinazolines in a straightforward manner. By employing the commercially available Ru3(CO)12/Xantphos/t-Bu OK catalyst system, a series of 2-aminoaryl methanols were conveniently converted in combination with different type of benzonitriles into various desired products in moderate to good yields upon isolation. The synthetic protocol proceeds in the presence of a commercially available ruthenium catalyst system with the advantages of high atom-efficiency, broad substrate scope and functional group tolerance, making it a highly practical approach for the preparation of various 2-arylquinazoline derivatives.