Reactivity Of Homoleptic Rare-earth Metal Aryloxide Based Intermolecular Frustrated Lewis Pairs Toward Small Molecules

The dissertation focuses on studying the application of homoleptic rare-earth metal aryloxide based intermolecular frustrated Lewis pairs in the activation of small molecules.In this study,homoleptic rare-earth metal aryloxide RE(OAr)3(RE=Sc(1),Y(2),Sm(3),La(4),Gd(5),Dy(6);Ar=2,6-tBu2-C6H3)serve as Lewis acids,while organic compounds containing phosphorus or nitrogen behave as Lewis bases.Many complexes in this study were characterized by single-crystal X-ray diffraction.1.Reactions of homoleptic rare-earth metal aryloxide based intermolecular frustrated Lewis pairs with organic azides.The reactivity of homoleptic rare-earth metal aryloxide based Lewis pairs toward organic azide substrates has been investigated herein.Treatment of RE(OAr)3(RE=La,Sm,Y,and Sc,Ar=2,6-tBu2-C6H3),PEt3 and Me3SiN3 in 2:1:1 molar ratio resulted in formation of separated ion pair complexes[Me3Si-PEt3]+[(ArO)3RE-N=N=N-RE(OAr)3]-under mild conditions.Replacement of phosphine with the nitrogen-containing Lewis base 1,4-diazabicyclo[2.2.2]octane(DABCO)produced analogous rare-earth azide complexes with[Me3Si-DABCO]+counterions.In contrast,reaction of the La(OAr)3/PEt3 Lewis pair with 1-adamantyl azide(AdN3)afforded the typical frustrated Lewis pair-type 1,1-addition product.A tetrahydrofuran ring-opening reaction was also observed for the resulting rare-earth azide complex with the[Me3Si-PEt3]+cation,with cleavage of the C-O bond by Si/P cooperation.Antiferromagnetic interactions for complexes 11,12 and 19 were determined by measuring the dc magnetic susceptibility.Alternating current susceptibility measurements revealed that the complex 12 exhibits single-molecule magnet behavior.2.Reactions of homoleptic rare-earth metal aryloxide based intermolecular frustrated Lewis pairs with α,β-unsaturated carbonyl complexes and other small molecules.The reaction with chalcone,1,2-dibenzoyl-ethylen or diazo compounds gave a Sc/P FLP type 1,4-addition product.The reaction with 5-phenyl-2,4-pentadienophenone and cyclopropyl phenyl ketone gave a Sc/P FLP type 1,6-addition product and 1,5-addition product.The reaction with phenyl isocyanate gave a Sc/P FLP type 1,2-addition product.The reaction realized ring-opening reaction on cyclohexene oxide.The reaction with late-transition-metal complex cleaved the Rh-Cl bond and produced a zwitterionic complex.