Synthesis Of Heterocyclic Compounds Via Multiconponent Reaction

Compared with the traditional synthetic methods, multicomponent reaction shortens the reaction steps, generates several or more new chemical bonds in one pot without separating intermediates, reduces the demand for initial reactants, requires less reaction time and separation operation, reduces the manpower and energy consumption. Because of its high convergence and flexibility, multicomponent reaction has become the focus in the modern organic synthesis.Compounds containing heterocyclic structure unit exist widely in nature, have important physiological and pharmacological effects.One-pot synthesis of 2-amino-3-cyano-4H-chromenes, 4,4'-?arylmethylene? bis?1H-pyrazol-5-ols? and 1,8-dioxo-decahydroacridines catalyzed by catalysts were researched. In addition, two porphyrins have been synthetized. The main research content is as follows:We have synthesized 2-amino-3-cyano-4H-chromenes by three-component condensation of aldehyde, 1-naphthol, malononitrile under reflux conditions using?NH₄?₂HPO₄ and EDDA as catalyst respectively with good to excellent yield between 64% and 94% in 20 min to 6.5 h. The recovered catalyst can be reused at least five additional times in subsequent reactions without considerable decrease in catalytic activity. Two possible mechanisms for the reaction catalyzed by?NH₄?₂HPO₄ and EDDA are proposed.We have synthesized 1,8-dioxo-decahydroacridines by three-component condensation of aldehyde, ammonium acetate and 5,5-dimethyl-1,3-cyclohexanedione under solvent-free condition at 130? using [BPy][H2PO₄] as catalyst with good to excellent yield between 70% and 94% in 15 min to 40 min. A possible mechanism for the reaction is proposed.We have synthesized 4,4'-?arylmethylene? bis?1H-pyrazol-5-ols? by three-component condensation of aldehyde, ethyl acetoacetate and phenylhydrazine under reflux condition at using potassium phthalimide as catalyst with good to excellent yield between 70% and 94% in 3 h to 8 h.The catalyst can be reused at least four additional times in subsequent reactions without considerable decrease in catalytic activity.We have also designed and prepared a new porphyrin which contains quaternary ammonium groups, make porphyrin react with metal salts, and gotten the metal porphyrins.