Synthesis Of NAD(P)H Model Compounds And Its Application In Biomimetic Catalysis

The nicotinamide adenine dinucleotide coenzyme [NAD(P)H] plays a crucial role in biological systems as a source of two electrons and a proton among the electron transport chain. The recent research involved a number of 1,4-dihydropyridine derivatives to be widely used as model compounds of NAD(P)H to mimic the reduction of biological systems makes them to be a hot point. Carrying out theses researches deeply could help to found a novel, efficient and green biomimetic catalyst, and further to expand it into organic catalysis.Being the fundamental working of the biomimetic catalysis system, this thesis is concerning a several typical reactions using the Hantzsch ester 1,4-dihydropyridine, diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (HEH) as reductant.Firstly, the aromatization of HEH was investigated in mild conditions by using hydrogen bromide as catalyst in 95% EtOH. A plausible mechanism for the reaction was proposed. The procedure for aromatization of HEH shows several advantages such as simple experimental operation, convenient isolated procedure, economic and environmentally benign.Secondly, converting a-halo ketones to corresponding ketones by using HEH as reductant in the presence of potassium iodide was described. The plausible mechanism of reductive dehalogenation was also presented.At last, as a continuation of the research work mentioned above, reductive dehalogenation of several a-halo ketones were carried out with equivalent Na2S2O4 in 95% EtOH in the presence of KI and HEH. The catalytic properties of HEH in the reductive dehalogenation with inorganic reductant were further investigated.In summary, HEH as model compound of NAD(P)H was successfully applied in several organic reactions, and the possible catalytic mechanism also investigated. This research can efficiently make a solid foundation stone for further study of biomimetic catalysis.