Catalytic Regioselective Nucleophilic Addition To Electron-Deficient Conjugated Enynes

Efficient regioselective reaction is an atom economy example of the cornerstones in modern synthetic green chemistry. Conjugated addition and tandem conjugated addition as the main methods to construct carbon-carbon bonds and carbon-hetero bonds have been reported by many chemists, and also an important way to achieve efficient regioselective reaction.In our research, we have developed efficient regioselective addition reactions of electron-deficient conjugated enynes with many kinds of nucleophiles. Many new coupounds such as highly substituted allenes, conjugated dienes and trienes, five member heterocycles, six member heterocylces or fused polycycles, even chiral heterocycles have been successfully achieved, which are present in most natural and synthetic molecules with potentially biological activity. Readily available starting materials, mild conditions, simple operation atom economy make these transform be very useful and attractive.This dissertation contains four parts.First of all, we developed the addition reactions of electron-deficient enynes with some single nucleophiles. In this part contains three aspects:the Michael additions of electron-deficient enynes with malonates, which gave highly substituted allenes; the Michael additions of electron-deficient enynes and heteroatoms, nucleophiles leading to poly-functionalized conjugated dienes or trienes; the last is the Michael additions of electron-deficient enynes and organometal reagents (such as copper lithium reagent and organozinc reagents), leading to highly substituted allenes too.Secondly, we studied the reactions of electron-deficient enynes with some binucleophiles. There are four aspects in this part:the [3+2] cycloadditions of electron-deficient enynes and carbon-oxygen binucleophiles, leading to2,3-dihydropyrroles were obtained; the [3+2] cycloadditions of electron-deficient enynes with hydroxyamine binucleophiles, afford2,3-dihydroisoxazoles; the [3+2] double Michael additions of electron-deficient enynes with hydrazine binucleophiles, furnish fully substituted and functionalized pyrazoles easily; the last aspect is about the [3+3] cycloadditions of electron-deficient enynes and carbon-oxygen binucleophiles, producing highly substituted pyrans.Thirdly, we solved the problem which produced by products in our conjuagated addition of electron-deficient enynes and some nucleophiles, and which a new hetero [4+2] cycloaddition reactions of electron-deficient enynes access to highly substituted pyrans of was developed.In the end, we developed some new chiral organocatalysts, which have been applied in the asymmertric [3+2] cycloaddition reactions of electron-deficient enynes and hydroxyamine, and affording optically active highly poly-functionalized2.3-dihydroisoxazles.