Synthesis Of Quinoline Compounds By Cyclization Of N-Methyl Aromatic Amines And Acetonitrile As Free Radical Preprecusors

Quinolines exist widely in nature,which are very significant heterocyclic compounds and structural fragments in the medicinal chemistry,and they play an important role in the field of medicine.In recent decades,the synthetic method of quinoline has made great progress.However,conventional synthetic methods are often accompanied by high cost of raw materials,expensive transition metal catalysts,excessive use of chemical oxidants,and harsh reaction conditions,still need to develop new synthetic methods of quinoline.Thus,this paper developed new method of synthesis by employing by the radical addition cyclization reaction of quinolines via cheap and easily available N-methylaniline and acetonitrile with ethylene dicarboxylate and cinnamamide compounds.This paper is mainly divided into two parts:1.The developments in activation of the o-nitrogen α-C-H bond of the photopromoted azo-methylarylaminesThe recent developments in photo-mediated o-nitrogen α-C-H functionalization of azo-methyl arylamines are introduced systematically,and the method of several different quinoline compounds by photosynthetic functionalization of o-nitrogen α-C(sp3)-H of several different N-methyl arylamine compounds are reported.At room temperature,the free radical[4+2]addition cyclization reaction using N-methyl-2-anilines and dimethylacetylene dicarboxylate as the raw materials under the irradiation of blue LEDs and the presence of Oxidant,20 8-arylquinoline compounds were generated and their structure were determined by X-ray diffraction(XRD)and nuclear magnetic resonance(NMR).The main advantages of this route involves inexpensive and effortless accessibility of raw materials,metal-free catalysis,mild conditions,and convenient operational simplicity,which provide a more green and efficient method for photosynthetic synthesis of quinoline derivatives.2.The research of addition cyclization by acetonitrile as free radical precursorThe synthesis method of quinolinones with acetonitrile as free radical precursor was reported.In this paper,the radical addition cyclization of various substituted 3,4-dihydroquinolinones alkaloids could be obtained by taking cinnamamides as raw material,Fe(Ⅲ)as catalyst,di-tert-butyl peroxide(DTBP)as free radical initiator,acetonitrile as solvent and cyanomethyl source at 120℃ for 12 hours.This reaction has good substrate universality and structure selectivity,and using inexpensive,readily available and environmentally friendly Fe salt as catalyst,provides an effective method for acetonitrile as free radical precursor to participate in the synthesis of quinolinone compounds.Figure[49]Table[8]Reference[117]...