| Environmentally friendly,simple,highly efficient and atomic-economic method is developing trend of organic synthetic chemistry.Considering of atomic-economy,highly efficiency and green chemistry,tandem reaction and multicomponent reaction strategies have been rapidly developed in recent years.Sometimes,complicated compounds can be obtained in one-pot and multi-step reaction via these synthetic strategies.Self-sorting behavior of molecular cluster-the ability to efficiently distinguish between self and nonself-is common property in complicated system.A novel synthetic reaction strategy-self-sorting tandem reaction which is a parallel tandem reaction pattern-is presented based on molecular self-sorting property in this thesis.Accordingly,an efficient carbon-carbon double bond-forming reaction from aryl methyl ketones(orα,β-unsaturated methyl ketones) is developed and a series of methylthio substituted five-numbered heterocycles are synthesized.In addition,new methods for iodination of carbonyl compounds and for convertion of aromatic ketones to the corresponding arenecarboxylic esters are found during the investigation of reaction mechanism.The main content is as follows:In chapter 1,carbon-carbon bond-forming is the most important reaction for the construction of organic molecules framework.Intermolecular carbon-carbon coupling pattern is summarized acorrding to the hybridized type of C-H bonds(sp,sp2 and sp3) and molecular self-sorting behavior is introduced.Subsequently,we put forward our design idea and research topics based on the above review.In chapter 2,on the basis of self-sorting behavior of molecular cluster,self-sorting tandem reaction which is different from classical tandem reaction and multicomponent reaction,has been presented for the first time.Accordingly,2-(methylthio)-2-butene-1,4-dionesⅡ-5 are prepared from aryl methyl ketones in the presence ofcopper(Ⅱ) oxide,iodine and dimethyl sulfoxide.The success of cross-coupling reaction of 4-chloroacetophenone with 2-acetylthiophene supports a hypothetical self-sorting tandem reaction mechanism.These 1,4-diketones are characterized by 1H NMR,13C NMR,IR and MS.In addition,compounds(Z)-Ⅱ-5,(E)-Ⅱ-5 and(Z)-Ⅱ-12 are further confirmed by X-ray single crystal diffraction.In chapter 3,twelveα,β-unsaturated methyl ketonesⅢ-2 are synthesized via classical aldol condensation reaction.Carbon-carbon double bond productsⅢ-3 are obtained via coupling of sp3 C-H bonds of two methyl groups in the presence of copper(Ⅱ) oxide,iodine and dimethyl sulfoxide. compound(E)-Ⅲ-3e is further confirmed by X-ray single crystal diffraction. In chapter 4,1,4-diketonesⅡ-5 are readily converted into the corresponding 3-methylthio 2,5-diaryl trisubstituted furansⅣ-16 in good yields in the presence of SnCl2/AcOH/HCl through a domino process.4-Bromo-3-methylthio 2,5-diaryl tetrasubstituted furansⅣ-19 are obtained either by the treatment of furansⅣ-16 with molecular bromine or of diketonesⅡ-5 with 30%hydrogen bromide in acetic acid solution in one pot.Removal of the methylthio group is accomplished by the treatment ofⅣ-16 with Raney Ni in ethanol which affords diaryl substituted furansⅣ-20 in excellent isolated yield.Selective reduction of the double bond of compoundsⅡ-5 by KI/HCl leads to the formation of the saturated 1,4-diketonesⅣ-22.3-Methylthio-2,5-diaryl substituted pyrrolesⅣ-23 and thiophenesⅣ-24 are synthesized by the reaction ofⅣ-22 with HCOONH4 or Lawesson's reagent respectively via the Paal-Knorr cyclization reaction.These synthesized compounds are identified by spectral analysis andⅣ-16b andⅣ-22c are confirmed by X-ray single crystal diffraction.In chapter 5,in refluxing methanol,aromatic ketones are transformed into the correspondingα-iodo ketones in good yields by the combination of copper(Ⅱ) oxide and iodine.The reaction mechanism shows that copper(Ⅱ) oxide plays a multiple role through random self-sorting.In chapter 6,on the basis of chapters 3 and 5,an efficient approach toα,β-unsaturatedα'-iodo ketones fromα,β-unsaturated ketones by selective iodination at theα'-position without effect on the double bond and the aromatic ring in the presence of copper(Ⅱ) oxide/iodine is described.This is the first systematical investigation of the synthesis of important intermediatesα,β-unsaturatedα'-iodo ketones directly fromα,β-unsaturated ketones.In chapter 7,it is found that aromatic methyl ketones,β-ketoesters,and trifluoromethyl-β-diketones can be directly converted to arenecarboxylic esters via carbon-carbon bond cleavage reaction in the presence of eopper(Ⅱ) oxide,iodine,pyridine,and potassium carbonate in alcoholic media.
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