【作者】 薛明强；

【导师】 沈琪；

【作者基本信息】 苏州大学 ， 有机化学， 2008， 博士

【摘要】 本论文以β–二酮亚胺基和苯基桥连β–酮亚胺基为配体,分别合成了31个稀土有机配合物,并对其中的22个稀土配合物以及苯基桥连β–酮亚胺配体进行了晶体结构鉴定。在此基础上,进一步研究了其中一些配合物对ε-己内酯(ε-CL)、L-丙交酯(L-LA)、丙烯腈(AN)的催化行为。主要结果如下:1. 2,4-二苯胺基-2-戊烯基锂Li(C6H5NC(Me)CHC(Me)NC6H5)(LHLi)以及2,4-二(4-氯苯胺基)-2-戊烯基钠Na(p-Cl-C6H4NC(Me)CHC(Me)NC6H4-p-Cl)(LClNa)和2,4-二(4-甲基苯胺基)-2-戊烯钠Na(p-Me-C6H4NC(Me)CHC(Me)NC6H4-p-Me)(LMeNa),分别与LnCl3按1:1的摩尔比反应,合成了3个相应的β–二酮亚胺基稀土二氯化物:LHYbCl2(THF)2 (1)、LClPrCl2(THF)2 (2)和LMeNdCl2(THF)2 (3)。这些配合物都经过了元素分析、红外光谱等表征。测定了1的单晶结构。2. 2,4-二(2,6-二甲基苯胺基)-2-戊烯基稀土二氯化物LMe2LnCl2(THF)2 (Ln = Yb, Nd; LMe2 = 2,6-Me2-C6H3NC(Me)CHC(Me)NC6H3-2,6-Me2)分别与LiNPh2以1 : 2的摩尔比反应,得到了相应的β–二酮亚胺基稀土胺化物LMe2Yb(NPh2)2(THF) (4)和LMe2Nd(NPh2)2(THF) (5),产物经红外光谱,元素分析等表征,并测定了它们的单晶结构。配合物4和5在温和条件下都可以作为单组份催化剂高活性地催化ε-己内酯聚合,也能有效地催化丙烯腈聚合。3. LMe2YbCl2(THF)2和2,4-二(2,6-二异丙基苯胺基)-2-戊烯基镱的二氯化物LiPr2YbCl2(THF)2 (LiPr2 = 2,6-i-Pr2-C6H3NC(Me)CHC(Me)NC6H3-2,6-i-Pr2)分别与芳氧钠以1 : 1的摩尔比反应,合成了具有单活性中心的β–二酮亚胺基稀土芳氧配合物LMe2YbCl(OAr’)(THF) (OAr’= 2,6-di-tert-butyl-phenoxide) (6)和LiPr2YbCl(OAr)(THF)2 (7) (OAr = 2,6-di-tert-butyl-4-metyl-phenoxide)。产物经红外光谱,元素分析等表征,并测定了配合物6的单晶结构。配合物6和7可以有效地引发ε-己内酯的可控开环聚合。4.合成了双β–二酮亚胺基稀土一氯化物(LCl)2YbCl(THF) (8)和(LCl)2PrCl(THF) (9),并对它们进行了全面的表征。晶体结构分析表明,配合物8具有6配位的扭曲八面体几何构型。5.β–二酮亚胺基锂盐LxLi分别与LnCl3按3:1的摩尔比反应,可以高产率地制得具有不同体积和电荷效应的均配型β–二酮亚胺稀土配合物(Lx)3Ln (x = Cl, LCl: Ln = Yb (10), Tb (11), Sm (12), Nd (13), Pr (14), La (15); x = H, LH: Ln = Yb (16), Sm (17), Nd (18); x = Me, LMe: Ln = Yb (19), Sm (20), Nd (21); x = F, LF (p-F-C6H4NC(Me)CHC(Me)NC6H4-p-F): Ln = Yb (22), Nd (23))。所有这些配合物都经过了元素分析、红外光谱等表征。测定了配合物10, 12-16, 18和20-23的单晶结构。配合物15还经过了1H NMR表征。结构鉴定显示所有均配型β–二酮亚胺基稀土配合物均是无配位溶剂的单分子结构。这些配合物是同构的,中心金属离子的配位数均为6,中心稀土离子的几何构型都可以描述成扭曲的八面体,六个顶点分别由三个β–二酮亚胺基中的六个配位氮原子占据。6.均配型β–二酮亚胺基稀土配合物除镱之外,都可以有效地催化己内酯的开环聚合,也可以作为单组份催化剂高活性地催化L-丙交酯聚合。稀土金属离子半径和β?二酮亚胺基上的电荷效应对催化活性有显著的影响。活性大小顺序为Pr > Nd > Sm > Yb,β–二酮亚胺基上有吸电子取代基的活性高于供电子的活性。这一实验结果表明,在β–二酮亚胺基稀土配合物中,β–二酮亚胺基不仅可以作为“旁观”配体,而且在一定条件下,也可以作为活性基团参与高分子合成反应。7.系统考察了均配型β–二酮亚胺稀土配合物加醇体系催化L-丙交酯聚合的特征。结果表明该体系在一定条件下可以极高活性催化L-丙交酯可控聚合。末端基分析表明引发L-丙交酯开环聚合的活性种可能是原位形成的稀土-烷氧键。8.以苯基桥连β–酮亚胺基(p-OC(Me)CHC(Me)N-C6H4-p-NC(Me)CHC(Me)O)H2 (LPhH2 (24))为辅助配体合成了双金属稀土配合物LPh[Yb(MeCp)2]2 (25)和LPh[Ln(OAr)2(THF)]2 (Ln = Yb (26), Sm (27), Nd (28), La (29))以及β–酮亚胺基(C6H5NC(Me)CHC(Me)O) (LH’)单金属镧配合物LH’La(OAr)2·THF (30)。这些配合物都经过了元素分析、红外光谱等表征,配合物29和30还经过了1H NMR表征。测定了配体24以及配合物25?27和29的单晶结构。9.合成了苯基桥连β–酮亚胺基双金属稀土配合物LPh[Yb(OAr)Cl(THF)]2 (31)和LPh[Yb(OAr)Cp(THF)]2 (32)。产物经过了元素分析、红外光谱等表征。配合物32的晶体结构显示,围绕每个中心镱离子的配位几何构型可以看作是一个扭曲的三角双锥。10.初步考察了部分苯基桥连β–酮亚胺基双金属稀土配合物对极性单体的催化行为,并与β–酮亚胺基单金属稀土配合物的催化性能进行了比较。结果表明,这类配合物可以高活性地催化ε-己内酯和L-丙交酯聚合,但可控性不好。更多还原

【Abstract】 Thirty-one organolanthanide complexes supported byβ-diketiminato and phenyl-bridgedβ-ketoimine were synthesized and well characterized. Among them, 22 complexes were further characterized by X-ray diffraction. The catalytic behaviors of these complexes for the polymerization ofε-caprolactone (ε-CL), L-lactide (L-LA) as well as acrylonitrile (AN) were examined. The main results obtained are as follows:1. Reaction of Li(C6H5NC(Me)CHC(Me)NC6H5) (LHLi), Na(p-Cl-C6H4NC(Me)CHC(Me)NC6H4-p-Cl) (LClNa), and Na(p-Me-C6H4NC(Me)CHC(Me)NC6H4-p-Me) (LMeNa), respectively, with LnCl3 in 1:1 molar ratio gave the corresponding complexes LHYbCl2(THF)2 (1), LClPrCl2(THF)2 (2), and LMeNdCl2(THF)2 (3). All complexes were characterized by elemental analysis and IR spectroscopy. The definitive structure of 1 was confirmed by X-ray diffraction.2. Reaction of LMe2LnCl2(THF)2 ( Ln = Yb, Nd; LMe2 = 2,6-Me2-C6H3NC(Me)CHC(Me)NC6H3-2,6-Me2) with LiNPh2 in 1:2 molar ratio gave the correspondingβ-diketiminato diamido complexes LMe2Yb(NPh2)2(THF) (4) and LMe2Nd(NPh2)2(THF) (5), respectively. Complexes 4 and 5 were characterized by elemental analysis, IR spectroscopy and X-ray diffraction. Complexes 4 and 5 were found to be the novel catalysts for ring-opening polymerization ofε-CL with high catalytic activity and for the polymerization of AN with good activity to give atactic polyacrylonitriles.3. Complexes LMe2YbCl(OAr’)(THF) (OAr’= 2,6-di-tert-butyl-phenoxide) (6) and LiPr2YbCl(OAr)(THF)2 (7) (OAr = 2,6-di-tert-butyl-4-metyl-phenoxide; LiPr2 = 2,6-i-Pr2-C6H3NC(Me)CHC(Me)NC6H3-2,6-i-Pr2) can be obtained by the reactions of LMe2YbCl2(THF)2 with NaOAr’and NaOAr, respectively, in 1:1 molar ratio. Both complexes were characterized by elemental analysis, IR spectroscopy. Complex 6 was further characterized by X-ray diffraction. These monoaryloxo ytterbium chlorides can act as a single-component initiator for ring-opening polymerization ofε-CL in a controlled manner.4. Reactions of LClLi and LClNa with LnCl3 in 2:1 molar ratio gave (LCl)2YbCl(THF) (8) and (LCl)2PrCl(THF) (9), respectively. Both complexes were characterized by elemental analysis, IR spectroscopy. The molecular structure of complex 8 was identified by single crystal X-ray diffraction.5. Reactions ofβ-diketiminato lithium LxLi with LnCl3 in 3:1 molar ratio afforded the complexes (Lx)3Ln (x = Cl, LCl: Ln = Yb (10), Tb (11), Sm (12), Nd (13), Pr (14), La (15); x = H, LH: Ln = Yb (16), Sm (17), Nd (18); x = Me, LMe: Ln = Yb (19), Sm (20), Nd (21); x = F, LF (p-F-C6H4NC(Me)CHC(Me)NC6H4-p-F): Ln = Yb (22), Nd (23)) in good isolated yields. All complexes were characterized by elemental analysis, IR spectroscopy, and 1H NMR spectroscopy for complex 15. The definitive molecular structures of 10, 12-16, 18 and 20-23 were provided by single crystal X-ray diffraction. These homoleptic tris-β-diketiminato-lanthanide complexes are isostructural. All of them have unsolvated monomeric structure with a six-coordinate lanthanide center ligated by six nitrogen atoms of three chelating bidentateβ-diketiminato ligands.6. It was first found that sterically demanding homoleptic tri-β-diketiminato-lanthanide complexes (except ytterbium one) are efficiently single-component initiators for the polymerization of L-LA andε-CL, demonstrating thatβ-diketiminato ligands serve not only as spectators, but also as an active groups in the polymerization of lactones. The reactivity of complexes depends both onβ-diketiminato group and central metal and the active order is Pr > Nd > Sm > Yb for metal and LCl > LH > LMe forβ-diketiminato ligand.7. Homolepticβ-diketiminato-lanthanide complexes in the presence of 2-propanol can initiate controlled polymerization of L-LA with extremely high activity under mild conditions. The terminal group analysis of an oligomer indicated the active species being in-situ generated Ln-alkoxide. 8. The bimetallic lanthanide complexes supported by a phenyl-bridgedβ-ketoimine (p-OC(Me)CHC(Me)N-C6H4-p-NC(Me)CHC(Me)O)H2 (LPhH2 (24)), LPh[Yb(MeCp)2]2 (25) and LPh[Ln(OAr)2(THF)]2 (Ln = Yb (26), Sm (27), Nd (28), La (29)), can be synthesized in high yields by the reactions of Yb(MeCp)3 and Ln(OAr)3 with LPhH2(24) in 2:1 molar ratio, respectively. Mono-β-ketoimine lanthanum complex [C6H5NC(Me)CHC(Me)O]La(OAr)2·THF (30) was prepared by the same reaction withβ-ketoimine. All complexes were characterized by elemental analysis, IR spectroscopy, and 1H NMR spectroscopy for complexes 29 and 30. The phenyl-bridgedβ-ketoimine 24 and complexes 25-27 and 29 were further characterized by X-ray diffraction.9. Complex LPh[Yb(OAr)Cl(THF)]2 (31) was prepaed by the reaction of Ln(OAr)2Cl with LPhH2 in 2:1 molar ratio. Treatment of 31 with two equiv. of NaCp afforded LPh[Yb(OAr)Cp(THF)]2 (32). Complexes 31 and 32 were characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction for 32.10. Preliminary studies revealed that the bimetallic lanthanide complexes supported by phenyl-bridgedβ-ketoimine can initiate effectively the polymerization ofε-CL and L-LA at room temperature, however, the polymerization was out of control.更多还原