Study On Cyanations Of Arylacetylenes And 2-arylmethyleneindan-1,3-diones

Orgainc cyanides are an important class of organic intermediates and have important synthetic applications in medicines,pesticides,materials and dyes.The introduction of cyano groups into molecules is an important strategy to increase molecular activity.Therefore,organic cyanation has always been a hot trend in organic chemistry.Currently,cyanide sources commonly used are metal cyanides,such as KCN,NaCN and CuCN,and nonmetal cyanides,such as HCN,TMSCN,AIBN and cyanohydrin.However,these cyanide sources have deficiencies such as strong toxicity,moisture sensitivity and difficulty in post-treatment.Potassium hexacyanoferrate(II)as a non-toxic and harmless chemical can avoid these deficiencies,so the use of potassium hexacyanoferrate(II)to synthesize organic cyanides is particularly important.Propionitrile contains two important functional groups,an alkynyl group and a cyano group,and has a wide range of applications in synthesis.It can be converted into a variety of compounds such as nitrogen-containing heterocycles,amides,amines and the like.The synthesis of propionitrile includes two types,one is to convert the propyne system to propionitrile,and the other is to directly cyanate the terminal alkyne.However,these methods all have the disadvantage that the cyanide source can be easily hydrolyzed and the reaction conditions are harsh.Therefore,it is very meaningful to develop a mild and efficient method for synthesis of propionitrile.In this thesis,the cyanation of arylacetylenes and 2-arylmethylene indan-1,3-diones were investigated,and propionitriles and ?-cyanodiketones were synthesized in high yield.Chapter 1: The applications of different types of cyanide reagents in organic cyanation are reviewed.And the applications of potassium hexacyanoferrate(II)as a green cyanide source are also summarized.In addition,synthetic methods and applications of propionitrile are also introduced.Chapter 2: A method for the direct cyanation of Csp-H of arylacetylenes using benzoyl cyanide as a cyanide source and copper as a catalyst to synthesize propargyl nitriles was described.The disadvantages of the method are mild conditions and high yield.A good yield could also be obtained by the gram-level reaction.Chapter 3: The conjugate hydrocyanation of 2-arylmethyleneindan-1,3-diones using potassium hexacyanoferrate(II)as a green cyanide source and benzoyl chloride as a promoter was described.2-(1,3-Dioxo-2,3-dihydro-1H-indan-2-yl)-2-arylacetonitriles were synthesized.The salient features of this method are green cyanide source,high yield and simple post-treatment procedure.