Ring Contractions Via Hypervalent Iodine Oxidation And Benzyne Mediated Reductive Cross-coupling Reaction

Included in this thesis are two parts of work:1)ring contractions of cyclobutanols to cyclopropyl ketones via hypervalent iodine oxidation.2)benzyne mediated reductive cross-coupling reaction.Corresponding abstracts are described as below:1.The hypervalent iodine chemistry has been significantly progressed in recent years.This project realized the ring constructions of cyclobutanonls to cyclopropyl ketones through hypervalent iodine oxidation.The reaction allows the synthesis of a wide range of aryl cyclopropyl ketones under mild and eco-friendly conditions.A variety of functional groups including aromatic or alkyl halides,ethers,esters,ketones,alkenes,and even aldehydes are nicely tolerated in the reaction.This is in contrast with traditional synthetic approaches for which poor functional group tolerance is often a problem.The practicality of the method is also highlighted by the tenability of hypervalent iodine oxidation system.Specifically,combining the iodine(?)reagent with an appropriate base allows the reaction to accommodate a range of challenging electron-rich arene substrates.The facile scalability of this reaction is also exhibited herein.Therefore,the reaction provides an effective method for synthesizing aryl cyclopropyl ketone.2.Benzyne is a unique highly reactive intermediate,which plays an important role in organic synthesis.Herein,we developed a benzyne mediated reductive cross-coupling of diarylsulfoxides.The reaction allows the production of a wide variety of biaryl compounds with excellent function group compatibility.Notable features of the procedure also include the easy operation,mild condtions,metal-free and environment-friendly,which make the method well complement to the traditional synthesis of biaryl compounds.Further mechanism studies and applications of the reaction are currently under way.