Studies On The Ag(I)-catalyzed Denitrative Trifluoromethylation And Photo-catalyzed Arylation Of Coumarins

Ag(I)-catalyzed denitrative trifluoromethylation of ?-nitrostyrenes and Photo-catalyzed C-H Arylation of coumarins have been investigated in this thesis.Section one focuses on Ag(I)-catalyzed denitrative trifluoromethylation of ?-nitrostyrenes with CF3SO2 Na.?-Trifluoromethylated styrenes are important trifluoromethylated compounds and key intermediates.The general methods introducing trifluoromethyl group are through leaving precursor,C-H activation and so on.There are some difficulties on denitrative trifluoromethylation of ?-nitrostyrenes in view of the inertia property of the nitro group,which raises the attention of some reserchers.Therefore,the development of a process on denitrative trifluoromethylation with mild reacting condition,high selectivationand good tolerance of functional groups has important significance in methodology and industrial value.In section one,after screening the catograry and dose of catalyst,solvents,additives and acids with ?-nitrostyrenes as main objects and 3.0 equiv CF3SO2 Na providing the CF3·,15 mmol% AgNO3 as catalyst,5.0 equiv DTBP as oxidant,0.2 equiv TBAI as phase transfer catalyst,1.0 equiv p-toluene sulfonic acid as additive,and DMSO/ CH2Cl2= 0.4/1 mL as solvent at 70? temperature in the atmosphere of Ar for 24 h was determined using as the optimal reaction conditions.This method has the advantages of using cheap and stable raw materials,high stereoselectivity and good tolerance for functional groups.Section two focuses on the Photo-catalyzed arylation between coumarin and diazonium tetrafluoroborate.3-Arylcoumarins with important biological activity and good fluorescence characteristic are obtained extensive attention by scientists.Therefore,the development of a process on synthesizing 3-arylcoumarins with mild reacting condition has important significance and industrial value.After screening the catograry and dose of catalytic,solvents,base,the optimal reaction conditions was obtained: 2.0 equiv diazonium tetrafluoroborate,1 mol % Ru(bpy)3PF6 as photo-catalyst,2 m L dry acetonitrile as the solvent,in the atmosphere of Argon for 12 h.Various functional groups substituted coumarins reacted with a lot of functional groups substituted diazonium tetrafluoroborate in one-pot,exploring the effects of functional groups to the reaction yield,synthesing 13 corresponding products with yield of 21-70%.What's more,the mechanism of the Photo-catalyzed reation was stated reasonably.