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1.
Reactions of the lithium salts of 3-substituted indenes 1, 2 with ZrCl 4(THF) 2 gave two series of nonbridged bis(1-substituted)indenyl zirconocene dichloride complexes. Fractional recrystallization from THF–petroleum ether furnished the pure racemic and mesomeric isomers of [(η 5-C 9H 6-1-C(R 1)(R 2)--- o-C 6H 4---OCH 3) 2ZrCl 2]· nTHF (R 1=R 2=CH 3, n=1, rac-1a and meso-1b; R 1=CH 3, R 2=C 2H 5; n=0.5 or 0, rac-2a and meso-2b), respectively. Complex 1a was further characterized by X-ray diffraction to have a C2 symmetrically racemic structure, where the six-member rings of the indenyl parts are oriented laterally and two o-CH 3O---C 6H 4---C(CH 3) 2--- substituents are oriented to the open side of the metallocene (Ind: bis-lateral, anti; Substituent: bis-central, syn). The four zirconocene complexes are highly symmetrical in solution as characterized by room temperature 1H-NMR, however 1H– 1H NOESY of meso-1b shows that some of the NOE interactions arise from the two separated indenyl parts of the same molecule, which can only be well explained by taking into account the torsion isomers in solution. 相似文献
2.
The compounds Cp 2VR (R = CH 3, C 2H 5, n-C 3H 7, n-C 4H 9, n-C 5H 11, CH 2C(CH 3) 3 or CH 2Si(CH 3) 3) have been prepared from Cp 2 VCl and RMgX in n-pentane. The air-sensitive compounds are stable at room temperature, but decompose between 65 and 138°C. The thermal stability decreases in the order R = CH 3 CH 2Si(CH 3) 3 > C 2H 5 > CH 2C(CH 3) 3 > n-C 5H 11 > n-C 4H 9 > n-C 3H 7. Compounds with R = i-C 3H 7 or t-C 4H 9 could not be obtained. 相似文献
3.
Mixed ketoiminate/ketoimine/pentamethylcyclopentadienyl (Cp*) complex of zirconium, [(η 5-Cp*){CH 3C(O)CHC(NHR)CH 3}{CH 3C(O)CHC(NR)CH 3}ZrCl 2] (R=4 -CF 3Ph) (3) has been prepared in high yield by the reaction of one equivalent of 4-CF 3-phenyl-β-ketoimine (1a) and one equivalent of lithium 4-CF 3-phenyl-β-ketoiminate (2a) with one equivalent of Cp*ZrCl 3 in Et 2O. Bis(ketoiminate)zirconium dichloride complexes, 4 and 6, have been also prepared in high yield by the reaction of amine elimination of ketoimine ligands, respectively 1a and 1b, with Zr(NMe 2) 4 and followed by chlorination reaction with TMSCl. The X-ray crystallography reveals that the compound 3 is based on distorted octahedral geometry containing a ketoimine and a ketoiminate. The ketoiminate ligand coordinates to the zirconium as a bidentate ligand, leaving the metal center coordinatively unsaturated and thus leading to an additional binding of a ketoimine ligand to the metal to stabilize the complex 3. The zirconium complexes 3, 4 and 6 provide the moderate activity for the polymerization of ethylene in the presence of MMAO cocatalyst. Low molecular weight and high density polyethylene was obtained. 相似文献
4.
文献报道了双(环戊二烯基)二硫氰基钛、锆、铪 [1-3]及双(甲基环戊二烯基)二硫氰基钛 [4]的合成。我们利用双(烷基环戊二烯基)二氯化钛、锆、铪与过量硫氰酸钾反应,合成了一系列新的双(烷基环戊二烯基)二硫氰基钛、锆、铪(见表1)。 相似文献
5.
4,4′-二溴联苯与n-BuLi反应得到对-联苯基二锂,再与四甲基环戊烯酮进行羰基加成,酸催化脱水,一步得到对-联苯基桥连四甲基环戊二烯配体4-(C 5Me 4H)C 6H 4-C 6H 4(C 5Me 4H)-4(1).配体1相继与n-BuLi和ZrCl 4反应得到相应的联苯基桥连双(单茂三氯化锆)4-(C 5Me 4ZrCl 3)C 6H 4-C 6H 4(C 5Me 4ZrCl 3)-4,不经分离直接与环戊二烯基锂或茚基锂反应得到相应的双核锆化合物4-(C 5MeZrCl 2Cp′)C 6H 4-C 6H 4·(C 5Me 4ZrCl 2Cp′)-4[Cp′=C 5H 5(2),C 9H 7(3)].研究了在MAO(MethylAluminoxane)助催化下,化合物2和3对乙烯聚合的催化性能.化合物2和3都显示了非常高的催化活性,并在较高的温度下达到最高活性. 相似文献
6.
UV/vis in diffusion reflection mode (DRS) and DRIFT spectroscopy have been used to study the surface zirconocene species formed at the interaction of Me 2Si(Ind) 2ZrCl 2 and Me 2Si(Ind) 2ZrMe 2 complexes with the MAO/SiO 2 support. Effect of additional activation of these catalysts with TIBA has been studied as well. Structure of type [Me2Si(Ind)2ZrMe]+[MeMAO]− (C) is formed at the reaction of Me2Si(Ind)2ZrMe2 complex with MAO/SiO2 (a.b. at 456 nm in UV/vis spectra). Interaction of this complex with TIBA results in the formation of new structure (D) with a.b. at 496 nm in UV/vis spectra. The surface species of different composition and structures are formed at interaction of Me2Si(Ind)2ZrCl2 complex with MAO/SiO2. The ratio between these species depends on the zirconium content in the Me2Si(Ind)2ZrCl2/MAO/SiO2 catalysts. According to the DRIFTS data (CO and ethylene adsorption) and ethylene polymerization data these catalysts contain active ZrMe bonds but activity of these catalysts at ethylene polymerization is low. Interaction of Me2Si(Ind)2ZrCl2/MAO/SiO2 with TIBA leads to the formation of the new cationic structure of type (D) with a.b. at 496 nm in UV/vis spectra and great increasing of activity at ethylene polymerization. 相似文献
7.
The directed oligomerization of propene and 1-hexene was carried out with a series of Cp′(C 5H 5)ZrCl 2 and Cp 2′ZrCl 2 pre-catalysts (Cp′=C 5HMe 4, C 4Me 4P, C 5Me 5, C 5H 4tBu, C 5H 3-1,3- tBu 2, C 5H 2-1,2,4- tBu 3) together with (C 5H 5) 2ZrCl 2. Oligomers in the molar mass range 300–1500 g/mol for propene and 200–3000 g/mol for 1-hexene were synthesized at 50 °C. The majority of oligomer molecules contain a double-bond end group. Oligomer characterization was carried out by gel permeation chromatography (GPC), 1H and 13C NMR. Vinylidene double bonds (from β-hydrogen elimination) are solely found for the tert-butyl-substituted zirconocenes and for most of the unsymmetrical methyl-substituted Cp′(C 5H 5)ZrCl 2 systems (except Cp′=phospholyl). With (C 4Me 4P)(C 5H 5)ZrCl 2 and with the symmetrical methyl-containing Cp 2′ZrCl 2 pre-catalysts, also vinyl end groups (from β-methyl elimination) are observed in the case of oligopropenes. The vinylidene/vinyl ratio depends on the ligand and the vinyl content increases from C 5HMe 4 (65/35) over C 4Me 4P (61/39) to C 5Me 5 (9/91). The phospholyl zirconocenes and (C 5HMe 4) 2ZrCl 2 also exhibit chain-transfer to aluminum thereby giving saturated oligomers. 相似文献
8.
The synthesis of the potential bridging ligand (C 6H 5) 2PCH 2CH 2Si(CH 3) 2C 5H 4 (3) is described. The ferrocene (6 derived from 3 has been found to form macrocyclic complexes with metal fragments NiCl 2, NiBr 2, and Co 2(CO) 6. Although monomeric, bimetallic products might have been expected based upon the reduced steric demands of ligand 3 relative to an analogous ligand, (C 6H 5) 2PCH 2Si(CH) 3) 2C 5H 4 (1), it appears that the increased flexibility in 3 is the overriding factor leading to a preference for inter- rather than intramolecular coordination of the second phosphine function in 6. 相似文献
9.
Isopinocamphyl-tosylate (2) was treated with indenyllithium to yield 3-(neoisopinocamphyl)-indene (3). Treatment of 3 with methyllithium gave 1-(neoisopinocamphyl)indenyllithium (4) which was then treated with 0.5 molar equivalents of ZrCl 4(thf) 2 to give a 52:48 mixture of one of the “ racemic-like” isomers of bis[1-(neoisopinocamphyl)indenyl]ZrCl 2 (5A) and its “ meso-like” diastereomer 5C. Hydrogenation of the 5A/5C mixture (50 bar H 2, Pt) furnished a mixture of the corresponding tetrahydroindenylzirconium complexes 6A and 6C, from which the “ meso-like” bis[1-(neoisopinocamphyl)-4,5,6,7-tetrahydroindenyl]zirconium dichloride diastereoisomer (6C) was isolated. Treatment of 6C with an excess of methylalumoxane in toluene/propene generated an active -olefin polymerization catalyst. At −30°C partly isotactic polypropylene (
η = 39000) was obtained. The catalyst derived from the chirally-substituted “ meso-like” metallocene complex 6C produced polypropylene predominantly under enantiomorphic site control. 相似文献
10.
An ethylene-bridged zirconocene complex bearing methyl substituents only on the cyclopentadienyl carbons adjacent to bridge point, ethylenebis(1,3-dimethylcyclopentadienyl)zirconium dichloride (5) was synthesized. Crystal structure of 5 was determined. The complex, 5, when activated with MAO, shows better comonomer incorporation ability than [Ph 2C(Fluo)(Cp)]ZrCl 2 in the ethylene–norbornene copolymerization but it is not better than rac-Et(Ind) 2ZrCl 2 for the ethylene-1-hexene copolymerization in terms of activity and comonomer incorporation. 相似文献
11.
Symmetrically-substituted epoxides react with fluorenyllithium to give the corresponding alcohols in high yields. These were used to prepare ansa-bridged mono(η 5-fluorenyl-zirconium complexes of the general formula [(C 13H 8---CHR---CHR---O]ZrCl 2(thf) 2 (CHR---CHR = cyclohexyl, cyclopentyl, 1,2-diphenylethyl). With Al(CH 3) 3 as cocatalyst these complexes catalyze the polymerization of ethene. 相似文献
12.
合成双(2,4-二甲基戊二烯基)氯化钆{[2,4-(CH 3) 2C 5H 5] 2GD cl} 2,并测定了晶体结构.晶体为单斜晶系,P2 1/n空间群.晶胞参数a=0.89141(18)nm,b=1.4486(3)nm,c=1.15925(15)nm,β=92.996(18)°,V=1.4949(4)nm 3,Z=3. 相似文献
13.
采用多种芳香双酯作为电子给予体制备了丙烯聚合高效催化剂,该催化剂具有高活性、聚合反应平稳、产物等规度高等特征.研究了多种芳香双酯和外加各种烷基硅氧烷对丙烯聚合的作用,测定了聚合反应动力学曲线,确定了聚合动力学方程.用扫描电镜研究了催化剂的形态,表明双酯组份能使催化剂结合得较紧密;对聚合产物的结构用DSD、红外光谱进行了表征. 相似文献
14.
The mono- and bis-cyclopentadienyl compounds 1-(Cp″)-4-(CH 3)C 6H 4 (1) and 1, 4-(Cp″) 2C 6H 4 (2) (Cp″ = 3,4-dimethylcyclopenta-1,3-diene-1-yl) have been synthesized. The reactions of the lithium salts of 1 and 2 with CpZrCl 3 · dme (dme = dimethoxyethane) and Cp*ZrCl 3(CP* = C 5(CH 3) 5) yielded the mono- and bi-nuclear bridged zirconocenes 1-(Cp″ZrCpCl 2)-4-(CH 3)C 6H 4 (3), 1,4-(Cp″ZrCpCl 2) 2C 6H 4 (4) and 1,4-(Cp″ZrCp*Cl 2) 2C 6H 4 (5). When activated with methylaluminoxane (MAO), the mono- and bi-nuclear zirconocenes 3 and 4 catalyse the polymerization of propene. The influence of the catalyst composition on the polymerization kinetics and molecular weight is discussed. 相似文献
15.
Two organogold derivatives of diphenylmethane and diphenylethane, Ph 3PAu( o-C 6H 4)CH 2(C 6H 4- o)AuPPh 3 (1) and Ph 3PAu( o-C 6H 4)(CH 2) 2(C 6H 4- o)AuPPh 3 (2), have been synthesized by the reaction of ClAuPPh 3 with Li( o-C 6H 4)CH 2(C 6H 4- o)Li and Li( o-C 6H 4)(CH 2) 2(C 6H 4- o)Li respectively. The interaction of 1 with dppe results in the replacement of the two PPh 3 groups to give a macrocyclic compound (3) that includes an Au Au bond. Compounds 1 and 2 react with one or two equivalents of [Ph 3PAu]BF 4 to form new types of cationic complex [CH 2(C 6H 4- o) 2(AuPPh 3) 3]BF 4 (4), [CH 2(C 6H 4- o) 2(AuPPh 3) 4](BF 4) 2 (5), and [(CH 2) 2(C 6H 4- o) 2(AuPPh 3) 4](BF 4) 2 (6). Complexes 1–6 have been characterized by X-ray diffraction studies, FAB MS, and IR as well as by 1H and 31P NMR spectroscopy. A complicated system of Au H-C agostic interactions, involving the bridging alkyl groups (—CH 2— and CH 2-CH 2—) of diphenylmethane and diphenylethane ligands, has been found to occur in complexes 1–3 and 6. 相似文献
16.
The carbonyl derivatized bis(alkyne) O=C(4-C 6H 4OCH 2CCH) 2 was converted into the imine derivatives RN=C(4-C 6H 4OCH 2CCH) 2 [R=OH, NHC(O)NH 2, NHC 6H 3-2,4-(NO 2) 2] and into the 4-bromomethyl-1,3-dioxolane derivative BrCH 2C 2H 3O 2C(4-C 6H 4OCH 2CCH) 2. The alkyne units in these compounds react with [AuCl(SMe 2)] in the presence of base to form the corresponding digold(I) diacetylide complexes, that exist as insoluble oligomers or polymers. They reacted with the diphosphines Ph 2PZPPh 2 [Z=CC, trans-HC=CH and (CH 2) n, n=3–5] to give macrocyclic gold(I) complexes of the type [Au 2(μ-LL)(μ-PP)], where LL is the diacetylide and PP the diphosphine ligand. The ability of these macrocyclic complexes to self-assemble to [2]catenanes has been studied. The ketone and imine derivatives do not form [2]catenanes because the orientation of the aryl groups is unfavorable, but the 1,3-dioxolane derivatives may catenate if the ring size is optimum. 相似文献
17.
Theoretical calculations (DFT, MP2) are reported for up to four sets of reaction products of trimethylphosphine, (CH 3) 3P, each with H 2O, HCl and HF together with DFT calculations on up to three sets of reaction products of substituted phosphonium cations, (CH 3) 3P–R +. These products comprise (a) P(III) normal complexes (CH 3) 3PHY, (b) P(IV) ‘reverse’ complexes Y(H–CH 2) 3P–R, (c) P(IV) ylidic complexes YHCH 2(CH 3) 2P–R and (d) P(V) covalent compounds Y–P(CH 3) 3–R for Y=HO, Cl and F and R=H, CH 3, C 2H 5, C 2H 4OH and C 2H 4OC:OCH 3. Calculations are carried out at the B3LYP/6-31+G(d,p) level in all cases and also at the MP2/6-31+G(d,p) level for systems in which R=H. Minimum energy structures are determined for predicted complexes or structures and geometrical properties, harmonic vibrations and BSSE corrected binding energies are reported and compared with the limited experimental information available. Potential energy scans predict equilibria between covalent trigonal bipyramidal P(V) forms and reverse complexes comprising hydrogen bonded or ion pair, tetrahedral P(IV) forms separated by low potential energy barriers. Similar scans are also reported for equilibria between reverse complexes and ylidic complexes for Y=OH and R=CH 3, C 2H 5, C 2H 4OH and C 2H 4OC:OCH 3. Corrected binding energies, structures and values of harmonic modes are discussed in relation to bonding The names ‘pholine’ and ‘acetylpholine’ are suggested for phosphorus analogues to choline and acetylcholine. 相似文献
18.
The siloxyanilines o-Me 3SiOC 6H 4NH 2 (1) and p-RMe 2SiOC 6H 4NH 2 (R=H (2); R=Me (3)), and their N-silylated derivatives p-Me 3SiOC 6H 4NHSiMe 3 (4) and p-Me 3SiOC 6H 4N(SiMe 3) 2 (5) have been prepared from ortho- or para-aminophenol and used in the synthesis of imido complexes. Thus, binuclear [{Ti(η 5-C 5H 5)Cl}{μ-NC 6H 4( p-OSiMe 3)}] 2 (6) and mononuclear [TiCl 2{NC 6H 4( p-OSiMe 3)}(py) 3] (7) imido complexes have been obtained from the reaction of 3 and [Ti(η 5-C 5H 5)Cl 3] or [TiCl 2(N tBu)(py) 3], respectively. In contrast, the reaction of 1 with TiCl 4 and tBupy affords the titanocycle [TiCl 2{OC 6H 4( o-NH)---N,O}( tBupy) 2] (8). Compound 5 has also been used to prepare the niobium imide complex [NbCl 3{NC 6H 4( p-OSiMe 3)}(MeCN) 2] (9), by its reaction with NbCl 5 in CH 3CN. These findings have been applied to the synthesis of polynuclear systems. Thus, chlorocarbosilane Si[CH 2CH 2CH 2Si(Me) 2Cl] 4 (CS–Cl) has been functionalized with the ortho- and para-aminophenoxy groups to give 10 and 11, respectively. The use of 11 has allowed the formation of the tetranuclear compound 12. Attempts to synthesize terminal imido titanium complexes from 10 and TiCl 4 in the presence of tBupy and Et 3N, give complex 8 and carbosilane CS–Cl. 相似文献
19.
Reaction of optically active ketone complexes (+)-( R)-[(η 5-C 5H 5)Re(NO)-(PPh 3)(η 1-O=C(R)(CH 3)] + BF 4− (R = CH 2CH 3, CH(CH 3) 2m C(CH 3) 3, C 6H 5) with K(s-C 4H 9) 3BH gives alkoxide complexes (+)-( RS)-(η 5-C 5H 5)Re(NO)(PPh 3)-(OCH(R)CH 3) (73–90%) in 80–98% de. The alkoxide ligand is then converted to Mosher esters (93–99%) of 79–98% de. 相似文献
20.
The monocyclooctatetraene uranium complex [U(COT)(I) 2(THF) 2] (COT=η-C 8H 8; THF=tetrahydrofuran), isolated from the reaction of bis(cyclooctatetraene)uranium with iodine, is a precursor for the synthesis of the alkyl derivatives [U(COT)(CH 2Ph) 2i (HMPA) 2], [U(COT)(CH 2SiMe 3) 2(HMPA)] (HMPA=hexamethyl phosphorous triamide) and [U(COT)CH 2SiMe 3) 3] [Li(THF) 3] and of the mixed-ring compounds [U(COT)(η-C 5R 5)(I)] (R=H or Me). The last were used to prepare the amide and alkyl complexes [U(COT)(η-C 5H 5)(N{SiMe 3} 2)] and [U(COT)(η-C 5Me 5)(CH 2SiMe 3)]. 相似文献
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