MBH Carbonates Participated Asymmetric Reactions Catalyzed By Phosphines And Design,Synthesis Of A Novel Chiral N,P-ligand

The whole dissertation mainly centers on MBH(Morita-Baylis-Hillman)carbonate as a kind of important “building blocks”.In our research the focus was mainly on two kinds of active dipole intermidiates formation in the presence of multifunctional chiral phosphines.And when its captured by the nucleophilic or electrophilic reagent,the allylation or cyclization products were obtained with high enantioselectivity.Besides,N,P-ligands have an excellent performance in many asymmetric reactions while transition-metal participated.Based on the successfully practice of PC-Phos developed by our group,we have attempted to remould this sort of good skeleton for further ligand design and synthesis of a new type of N,P-ligand.The detailed contents of dissertation including the following three parts:In the first part,based on the ?-aminophosphine catalysts derived from(R)-tertbutylsulfinamide in our group,a highly enantioselective allylic alkylation of(trifluoromethyl)indenes with MBH carbonates for the preparation of trifluoromethylsubstituted chiral indene ring compounds.Research has shown that the allylation process of(trifluoromethyl)indenes can take place smoothly using phosphine catalyst with simple isopropyl group as the side chain,ledding to allylation products in 85% highest yield with up to 97% ee under 10 mol% catalyst loading.It is noteworthy that the reaction process can be compatible with alkyl-(trifluoromethyl)indenes,alkenyl-(trifluoromethyl)indenes or the mixture of both.Therefore.It has a good substrate scope.For the second part,we have successfully developed asymmetric [3+2] cycloaddition of 2-nitrobenzofurans and MBH carbonates for the construction of dihydrobenzofuran derivatives by using Peng-Phos catalyst.The dearomatization products was obtained in 97% highest yield with up to 97% ee.Meanwhile,a wide of dihydrobenzofuran derivatives were compatible with dearomative process to give high ee values and moderate to excellent yields under mild condition.And the third part,PC-Phos have successfully been applied into gold-catalyzed asymmetric intramolecular cyclization of N-allenamides and the synthesis of chiral sulfoxides catalyzed by palladium.We have attempted to design and synthesis of a new type of N,P-ligand by using xanthene skeleton.In addition,we also made some effort for the application of this ligand in Pd(II)-catalyzed organoboron-mediated Heck-type reaction and allylation.At present,we have not found a suitable application for it and further study is still in due course.