Reactions of equalmolar ratios of MnCl2 4H2O and the tridentate ligands 2,6-bis[ 1-(2,6-dimethylrnphenylimino) ethyl] pyridine ( L1 ), 2,6-bis [ 1-( 2,6-diethy phenylimino ) ethyl ] pyridine ( L2 ), and 2,6-bis rn[ 1-(2,6-dimethylphenylimino) ethyl ] pyridine ( L3 ) in acetonitrile afforded the five-coordinated complexes rnL1Mn( Ⅱ )Cl2 CH3CN(1), L2Mn( 11 )Cl2 CH3CN(2) and L3Mn( 1Ⅱ )Cl2 CH3CN(3), respectively. The rnthree complexes were characterized using elemental analysis, IR spectroscopy and single-crystal X-ray diffracrntion. Crystallographic studies on complexes 1——3 reveal the pentacoordinate with geometries that can be best rndescribed as distorted trigonal bipyramidal. Complex 1 crystallizes in the monoclinic system, space group P21/rnn, with a = 1.3304 (3) nm, b = 1.4864 (3) nm, c = 1.4423 (3) nm; β = 108.41 (3)°,rnV = 2. 7063 (9) nm3, Z = 4, F (000) = 1116, R1 = 0. 0465; complex 2 belongs to monoclinic system with rnspacegroupP21/c, witha=l.2919(1) nm, b=1.5283(1) nm, c=1.6362(1) nm;β=99.27(1)°, V=rn3. 1883(3) nm3, Z =4, F(000) = 1244, R1 = 0. 0599; complex 3 belongs to monoclinic system with space rngroup P21/n, with a = 1. 4542 (3) nm, b = 1. 5083 (3) nm, c = 1. 4646 (3) nm; β = 112. 56 (3) o, V =rn2. 9667(10) nm3, Z＝＝4, F(000) = 1180, R1 = 0. 0627. Complexes 1——3 exhibit lower catalytic activities rnfor ethylene polymerization after activation with cocatalysts of [Ph3 C ] + [B (C6Fs )4 ] .%由三齿含氮配体2,6-二[1-(2,6-二甲基苯基亚胺)乙基]吡啶(L1)、2,6-二[1-(2,6-二乙基苯基亚胺)乙基]吡啶(L2)和2,6-二[1-(2,4,6-三甲基苯基亚胺)乙基]吡啶(L3)分别与MnCl2·4H2O在乙腈中反应,合成了3个新的具有较大空间位阻的2,6-吡啶二亚胺基氯化锰配合物L1Mn(Ⅱ)Cl2·CH3CN(1),L2Mn(Ⅱ)Cl2·CH3CN(2)和L3Mn(Ⅱ)Cl2·CH,CN(3).采用元素分析、红外光谱和X射线单晶衍射对配合物1～3进行了结构表征.单晶X射线衍射分析结果表明,3个配合物均为五配位扭曲三角双锥构型,属单斜晶系.配合物1属于P21/n空间群,晶胞参数a=1.3304(3)nm,b=1.4864(3)nm,c=1.4423(3)nm;β=108.41(3)°,V=2.7063(9)nm3,Z=4,F(000)=1116,R1=0.0465.配合物2属于尸21/c空间群,晶胞参数a=1.2919(1)nm,b=1.5283(1)nm,c=1.6362(1)nm;β=99.27(1)°,V=3.1883(3)nm3,Z=4,F(000)=1244,R1=0.0599.配合物3属于P21/n空间群,晶胞参数a=1.4542(3)am,b=1.5083(3)nm,c=1.4646(3)nm;β=112.56(3)°,V=2.9667(10)nm3,Z=4,F(000)=1180,R1=0.0627.研究了配合物1-3在经有机硼助催化剂[Ph3C]+[B(C6F5)4]-活化后对乙烯聚合的催化性能.
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