Synthesis Of ?-diimine Pd(?) Complexes With Spatial Stereo Geometric Configuration And Their Catalytic Copolymerization Of Norbornene And Polar Monomer

In this paper,a series of different N-aryl groups stereo configuration of?-diimine ligands {9,10-dihydro-9,10-ethanoanthracene-11,12-di(Ar)imine(Ar=benzyl,L1;Ar=benzhydryl,L2;Ar=trityl,L3)} were synthesized by condensation reaction of 9,10-dihydro-9,10-ethyleneanthracene-11,12-dione with benzylamine,benzylamine and tribenzylamine.The ligands L1-L3 and tetraethylammonium palladium tetrachloride {(Et4N)2PdCl4} were coordinated to obtain a series of three-dimensional geometric configuration bis-(a-diimine)palladium complexes Cl{Pd(Ll)2Cl2},C2{Pd(L2)2Cl2} and C3{Pd(L3)2Cl2};And the ligands L1,L2,L3 were coordinated with cyclooctadiene methyl palladium chloride{(COD)MePdCl}and triphenylphosphine(PPh3)to obtain ?-diimine palladium complexes C4{PdL1(PPh3)Me},C5{PdL2(PPh3)Me} and C6{PdL3(PPh3)Me} with weak coordination group triphenylphosphine.C1-C3 activated by MAO showed excellent catalytic effect in the homopolymerization of norbornene(NB),more critical was C1-C3 could catalyze the copolymerization of norbornene and MMA efficiently,C4-C6 could catalyze the copolymerization of norbornene and 5-norbornene-2-methanol.The steric hindrance effects of catalysts,different reaction conditions,different catalyst and cocatalyst ratios and different monomer feed ratios in norbornene(co)polymerization were also discussed.The chemic structure of catalysts was characterized by 1H NMR and MS.The obtained copolymers were confirmed by spectras,and their thermodynamic was also studied.The optimal reaction conditions were found in the homopolymerization process of norbornene catalyzed bis-(?-diimine)palladium complexes C1,C2 and C3,namely NB/Pd=2000/1,Al/Pd=2000/1 and reaction temperature Tp=60?.Under the optimal conditions,the catalytic activity of these catalysts was as high as 107 g·mol-1·h-1 in the homopolymerization of norbornene.When Al/Pd=2000/1,NB/Pd=2000/1,and reaction temperature Tp=60?,these catalysts could catalyze the copolymerization of norbornene with MMA and the catalytic activity could reach 104 g·mol-1·h-1.It was also found that with the increase of the number of benzene rings on the N-aryl group,the catalytic effect would first become stronger and then weaker.The chemic structures of the obtained copolymer were verified by 1H NMR,FTIR and so on.Thermodynamic tests of the copolymers showed that they had good thermal stability.The optimal reaction conditions for the homopolymerization of norbornene catalyzed by ?-diimine palladium complex C4-C6 with triphenylphosphine were NB/Pd=2000/1,B/Pd=20/1,Al/Pd=1000/1,reaction temperature Tp=100?.In the copolymerization of norbornene and 5-norbomene-2-methanol,C5 had good catalytic activity at 100? and reached 105 g·mol-1·h-1.It could be caused by temperature and steric effect.The obtained polymers were tested by WXRD.The results showed that the crystallinity of the copolymers was low.