Study On The Aryl-etherification Reactions Of Alkynes Mediated By Bisarylated Hypervalent Iodine Salts

Bisarylated hypervalent iodine salts are high electrophilic arylation reagents with wild, stable and high selectivity properties. Oxygen-heterocycle compounds are widely used in modern organic synthesis chemistry, applied in the formation of complex material moleculars and pharmaceutical drugs, acting as industrial chemicals or synthetic intermediates. Also, oxygen heterocycles are privileged scaffolds in various natural products and bioactive moleculars.A novel aryl-etherification reaction of alkoxyl alkynes mediated by bisarylated hypervalent iodine salts was reported, enriched the content of diaryliodoniums electrophilic cyclization methodology. Taking advantage of the highly electrondeficent nature and excellent leaving-group ability of bisarylated hypervalent iodine salts, the Cu-catalyzed reactions proceed smoothly to give useful oxo-heterocycles with alkoxyl alkynes via cleavage of a strong C-O bond. Plausible mechanism for this intramolecular aryl-etherification reaction was also discussed in this work. The new method features mild reaction condition, high yields and simple operation.In this thesis, 26 oxygen-heterocyclic compounds were synthesized, including of 19 dihydropyran derivetives(NMR yields 31%-96%), 3 dihydrofunan derivetives(NMR yields 57%-78%) and 4 benzofunan derivetives(isolated yields 23%-40%), among which 18 compouds including 6-phenyl-5-(p-tolyl)-3,4-dihydro-2H-pyran et al. were reported for the first time. In addition, futher functionalization of oxygen heterocycle product afforded 3,4-dihydro-2H-dibenzo chromene(isolated yield 63%), 2,3-diphenyltetrahydro-2H-pyran(isolated yield 85%) and 4,5,5-triphenylpent-4-en-1-ol(isolated yield 76%), among which 6-phenyl-5-(p-tolyl)-3,4-dihydro-2H-pyran and 2,3-diphenyltetrahydro-2H-pyran were synthesized for the first time. The structures of all separated target products were characterized by 1H NMR, 13 C NMR, and GC-MS. The molecular structure of 6-(4-bromophenyl)-5-phenyl-3,4-dihydro-2H-pyran was confirmed by X-Ray diffraction analysis.The research subject, be of great importance on hypervalent iodine chemistry and oxygen heterocycle chemistry, enriched the methodology contents of these fields, having significance in both theory and application.