| The applications of organozinc reagent in organic synthesis have been limited for a long time although it is one of the earliest prepared organometallics. The reason is that it is inactive towards most of electrophiles except Refonnatsky reagent. However, investigation in recent years shows that the organozinc reagent can react with a range of electrophiles in the presence of a Lewis acid and by the catalysis of transition metal complex or salts. Mort importantly, a variety of organozinc halides (RZnX) can be conveniently obtained by the oxidative insertion of zinc into R-X and they can tolerate a wide range of functionalities such as carbonyl, ester, halide and cyano group. These functional groups can be directly introduced into target molecules. And possibly a shorter synthetic route would be realized by avoiding the use of protection-deprotection steps as well as functional group interconversions.Although its application in organic synthesis has extended rapidly, a survey of literature shows that the reactivity of organic zinc halides are lower than diorganozincs and in most cases, they doesnt react with most electrophiles until these reagents are transmetalated to corresponding organometallic reagents by CuCN or other transition metallic salts. So in this thesis we want to use microwave irradiation which has been broadly used to accelerate organic reaction in recent years to activate the reactivity of FG-PhCHiZnX when it react with some electrophiles such as aroyl chlorides, 1 -aryl-2-nitroethenes and so on.This thesis includes five chapters.Chapter One: The Development of Polyfunctional Organozinc Halides in Organic Synthesis.In this section, the development, preparation and application of organozincs, especially the functional organozincs, are reviewed in details.Chapter Two: Palladium(II)-Catalyzed Cross Coupling Reaction of Functionalized BenzylzincHalides with Aroyl Chlorides under Microwave Irradiation.The cross coupling reactions of functionalized benzylzinc halides (FG-PhCHiZnX) witharoyl chlorides catalyzed by Pd(PPh3)2Cl2(2mol%) under microwave irradiation was first reported. The results show that when Pd(PPh3)2Cl2 as the catalyst , FG-PhCH2ZnX can smoothly coupled with aroyl chlorides under microwave irradiation to give the coupling products in excellent yields. From the viewpoint of organic synthesis methods and application of microwave in organic synthesis, this method is a new, convenient work-up, fast, and affords good yield. The reaction mechanism also proposed on the basis of experiments and the literatures. And ten products were synthesized by this procedure.Chapter Three: Study of the Substitution Reaction of Functionalized Benzylzinc Halides with a -Nitrostyrene under Microwave IrradiationIn chapter 3, a microwave- irradiated reaction of Functionalized benzyl zinc reagents with a -nitrostyrene was reported. Microwave methodology was first introduced into the reactions of Functionalized benzyl zinc reagents with 1 -aryl-2-nitroethenes. The experimental results show that nitro group of a -nitrostyrene can be rapidly substituted by functionalized benzylzinc halides (FG-PhCHiZnX) under microwave irradiation in the presence of Ni(acac)2 or in the absence of catalyst with lower yield of products. The effects of irradiation power, time, and various solvents on the reaction were investigated. We broaden the scope of the microwave application and posted a new method for synthesis of 1,3-diarylpropenes. The reactions finished in 9 or 12 minutes and with satisfactory yields. So the reaction has following advantages: rapid reaction speed, convenient manipulation and excellent yields of products.Chapter Four: Palladium(II)-Catalyzed Olefmation Reaction of Functionalized Benzylzinc Halides with Aromatic Aldehydes.In this part, a reaction of benzyl zinc halides with aromatic aldehydes catalyzed by Palladium complexes was first reported. Under the catalysis of Pd(PPh~3)2Cl2 and TMSCl, these reactions could be proceeded efficiently giving high yield of functionalized stilb...
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