The Synthesis And Application Of Phosphoryl Atropisomer And Desymmetrization Of Cyclic Diaryliodoniums

This dissertation has two parts which could be divided into three chapters:The first part mainly focused on the Pd-catalyzed asymmetric synthesis of axially chiral Phosphoryl vinyl arene.And a class of structurally unique cyclic phosphine oxides were synthesized through simple transformation.The second part mainly studied the enantioselective ring opening of cyclic diaryliodoniums.According to the crystal structure of cyclic diaryliodonium salt,a stereochemical model was proposed to rationalize the stereochemical outcome.The first chapter:enantioselective synthesis of atropisomeric vinyl arene compounds via palladium catalysis.The axially chiral vinyl arenes,catalyzed by palladium and TADDOL-based phosphoramidites,were obtained from aryl bromides and hydrazones.The reaction proceeded uneventfully with excellent yield and enantioselectivity.The products could be readily reduced to abtain the(P,Olefin)ligand,or oxidized to form the axially chiral biaryl compound.The second chapter:the synthesis of phosphole by t-BuLi-mediated aryl migration.The brominations occurred at the alkene moiety of phosphine oxides vinylarenes.Then the synthesis of phosphole via t-BuLi-mediated rearrangement could be achieved.The relative migration rate of aryl rings with different electronic properties was also briefly investigated.And the enantiomeric purity would be partially-lost for chiral substrate.The third chapter;desymmetrization of six-membered cyclic diaryliodoniums.The chiral diarymethanes could be abtained by Cu-catalyzed enantioselective ring opening reaction of six-membered cyclic diaryliodoniums with potassium carboxylic or thioacids.The Cyclopropyl bis(oxazoline)ligand well discriminates two C-I bonds of cyclic diaryliodoniums.A stereochemical model was proposed on the basis of the crystal structure of cyclic diaryliodonium salt.