Synthesis Of β-cyano-α,β-unsaturated Ketones And 1,2,3-triazolyl-based Ketoximes Directly Using Calcium Carbide As A Solid Acetylene Source

Calcium carbide is a kind of cheap,stable and commercial available solid.Because it is commonly used in industry to prepare acetylene gas and acetylene-based chemical products,it is known as―the mother of organic synthesis industry‖.When calcium carbide is used to prepare organic chemicals in the traditional process,it is first reacted with water to convert it into acetylene gas,and then organic chemicals can be synthesized through acetylene gas.The flammable and explosive characteristics of acetylene make it relatively difficult to operate,the conditions required to participate in the reaction are harsh,and transportation and storage are inconvenient.Recent reports indicate that calcium carbide can be directly used as a sustainable,low-cost,and easy-to-handle raw material,and is an effective source of acetylene gas for in-situ chemical conversion.This research not only reduces the need for complex equipment,but also simplifies the traditional steps for preparing organic chemicals from acetylene.Therefore,calcium carbide has replaced acetylene gas to synthesize important organic chemicals and has become a more convenient,safer and more effective solid raw material.β-cyano-α,β-unsaturated ketones are significant intermediates for the synthesis of fine chemicals,and are usually found in drugs,pesticides and fragrances.At the same time,the substances containingβ-cyano-α,β-unsaturated ketone moieties also have great potential application value.For example,they can be used as a calcium-channel blocker（treating hypertension,cerebral artery occlusion and Alzheimer’s disease）and as a new type of near-infrared dye.In recent years,a few synthetic methods forβ-cyano-α,β-unsaturated ketones have been reported.However,there are a number of problems with these existing methods,such as environment-unfriendly reagents,limited sources of raw materials,lengthy synthetic steps and unsafe cyanide sources.Therefore,it is necessary to develop a more green and practical method for the synthesis ofβ-cyano-α,β-unsaturated ketones.As an important class of nitrogen-containing heterocyclic compounds,1,2,3-triazoles have unique properties.It is widely used in the design and development of new drugs because of the wide range of biological activities such as antibacterial,antiviral,anti-HIV and anti-malarial activities.In recent years,the report for the synthesis of 1,2,3-triazolyl-based ketoximes are particularly scarce.Only the synthesis of 4-substituted 1,2,3-triazolyl-based ketoximes has been reported.4-Unsubstituted 1,2,3-triazolyl-based ketoximes were not reported because their synthesis had to use difficult-to-handle acetylene gas as a raw material.Therefore,it is necessary to explore a new route for the synthesis of4-unsubstituted 1,2,3-triazolyl-based ketoximes.This thesis focuses on the one-pot four-conponent synthesis of a series ofβ-cyano-α,β-unsaturated ketones using calcium carbide as a solid acetylene source,potassium hexacyanoferrate（II）as a green cyanide source,various aroyl chlorides and various iodoaromatic hydrocarbons as substrates;and the synthesis of a series of 1,2,3-triazolyl ketoximes by using calcium carbide as a solid acetylene source to react with（Z）-2-azido-1-arylethan-1-one oximes.The main contents of this thesis are as follows:Chapter 1:This section mainly reviews the research progress of calcium carbide in organic synthesis,and the synthesis and application progress ofβ-cyano-α,β-unsaturated ketones and 1,2,3-triazolyl-based ketoximes.Chapter 2:Using palladium as a catalyst,calcium carbide as a cheap and easy-to-handle acetylene source,potassium hexacyanoferrate（II）as an environmentally-friendly green cyanide source,various aroyl chlorides and various iodoaromatic hydrocarbons as substrates,a series ofβ-cyano-α,β-unsaturated ketones were synthesized by one-pot four-component procedures.The method has the salient features of high yield,low cost,simple work-up procedures.A gram-scale reaction further demonstrates the efficacy of this synthetic method.Chapter 3:A series of 1,2,3-triazolyl-based ketoximes were synthesized directly using calcium carbide as a solid acetylene source and（Z）-2-azido-1-arylethan-1-one oximes as starting materials.The method has simple and easy operation,uses cheap solid acetylene source,high reaction yield,cheap copper catalyst,and simple work-up procedures.At the same time,this method will be a good alternative to synthesize a wide range of1,2,3-triazolyl-based ketoximes.The above products structures were further characterized by ¹H NMR,¹³C NMR and HRMS.