The chloromethylation reaction of substituted titanocenes (η~5-C_5H_5)(η~5-C_5H_4CRR'C_6H_4X)TiCl2 1 in the presence of polyformaldehyde and dry hydrogen chloride isreported.
Seven new binuclear titanocenes with different linking bridges, unsubstituted or substituted on the Cp rings, were synthesized and tested for their effect on ethylene polymerization in the presence of MAO. The polyeth...Seven new binuclear titanocenes with different linking bridges, unsubstituted or substituted on the Cp rings, were synthesized and tested for their effect on ethylene polymerization in the presence of MAO. The polyethylenes thus obtained had broad MWD or even bimodal GPC curves, as compared with that from two reference mononuclear titanocenes. This is explained by the difference in degree of steric hindrance around the active center sites imposed by the bulky substituted ligands assuming different configurations in the rotation of the catalyst molecules. Lower polymerization temperatures alleviate the effect of these configuration differences, as reflected in change in MW and (M) over bar(w)/(M) over bar(n). This effect is not caused by decomposition or disproportionation of the binuclear titanocenes as evidenced by the stability of the catalyst.展开更多
The effects of the substituents on the cyclopentadienyl ring and the reducing agents on the catalytic activity and the stability of titanocene/NaH or n BuLi systems for the hydrogenation of olefins were investiga...The effects of the substituents on the cyclopentadienyl ring and the reducing agents on the catalytic activity and the stability of titanocene/NaH or n BuLi systems for the hydrogenation of olefins were investigated. For the catalyst systems composed of titanocene/NaH or n BuLi, the nature and the number of the substituents on the cyclopentadienyl ring control the catalytic behavior of those two systems. The effect of the reducing agent on the catalytic activity is relatively small. In addition, the characters of the hydrogenation of various olefins catalyzed respectively by Cp 2TiCl 2/NaH or n BuLi systems were compared.展开更多
Cyclopentadienyl)[η￣5- (1-(4-methoxyphenyl)cyclohexyl)-cyclopentadienyl]titanium dichloride has been synthesized through a novel modified reaction route. The molecular structure of the title complex was determined b...Cyclopentadienyl)[η￣5- (1-(4-methoxyphenyl)cyclohexyl)-cyclopentadienyl]titanium dichloride has been synthesized through a novel modified reaction route. The molecular structure of the title complex was determined by single-crystal Xray diffraction. Crystallographic data: C_(23)H_(26)Ocl_2Ti· 0. 3C_6H_(14),M_r=462. 44, triclinic, P1, a=11. 704(2) , b= 16. 340(4) , C=6. 824(1), a=90. 51(2) , β= 106. 98(1), γ=69. 82(2)°, V= 1165. 4(4) , Z=2, D_c= 1. 317 g/cm￣3, μ(MoKa) = 6. 2cm￣(-1), F(000) = 486 , and the final R= 0. 059 and R_w= 0. 085 for 2723 observed reflections with I>3σ(I). The cyclopentadienyl ring is symmetrically bonded to Ti(Ti-C distances 2. 361 (5)～2. 386 (5)) but the substituted cyclopentadienyl ring is asymmetrically bonded (Ti C2. 327 (4)～2. 438 (4)). The solvent petroleum-ether is disordered in the crystal.展开更多
Reduction of diaryldiselenides by the system of Cp2TiCl2/Bu'MgBr/THF gave the nucleophilic arylselenium complex. They reacted with diaryl iodonium salts to afford unsymmetrical diaryl selenides in high yields.
The diaryldiselenides reacted with titanocene hydried （Cp2TiH） generted from Cp2TiCl2/i-BuMgBr to give arylselenium complexes of titanocene. They reacted readily with diaryliodoiums salt to give unsymmetical diaryls...The diaryldiselenides reacted with titanocene hydried （Cp2TiH） generted from Cp2TiCl2/i-BuMgBr to give arylselenium complexes of titanocene. They reacted readily with diaryliodoiums salt to give unsymmetical diarylselenides.展开更多
The FT-IR and FT-Raman spectra of complexes (C5H5)2TiCl2(Ⅰ), (C5H4Me)2TiCl2 (Ⅱ) and (C5HMe4)2TiCl2(Ⅲ) have been obtained and discussed. The FT-Raman spectral data pro- vide some new vibrational information about co...The FT-IR and FT-Raman spectra of complexes (C5H5)2TiCl2(Ⅰ), (C5H4Me)2TiCl2 (Ⅱ) and (C5HMe4)2TiCl2(Ⅲ) have been obtained and discussed. The FT-Raman spectral data pro- vide some new vibrational information about complexes (Ⅰ), (Ⅱ) and (Ⅲ). The assignments of cyclopentadienyl vibrational modes and skeletal vibrational modes have been made.展开更多
Eight comptexes (RC_5H_4)_2Ti(O_2CA_r)_2(R=H,CH_3;Ar= with 2 equiv.N_aO_2CA_r.The carboxytate ligands in the complexes coordinate to titan^um atom in monodentate mode.(CH_3C_5H_4)_2Ti(O_2CC_4H_3S-2)_2 has four-coordin...Eight comptexes (RC_5H_4)_2Ti(O_2CA_r)_2(R=H,CH_3;Ar= with 2 equiv.N_aO_2CA_r.The carboxytate ligands in the complexes coordinate to titan^um atom in monodentate mode.(CH_3C_5H_4)_2Ti(O_2CC_4H_3S-2)_2 has four-coordinate bent titanocene in which the thiophencarboxyaltes are a monodeotate ligand(Ti-0=1.981(8)A,1.926(3)A;) 0-Ti-0:91.6(8)~ ; Ti-C:2.333-2.440A).展开更多
1 Results The lecture will address aspects of functional organometallics related to the development of novel organometallic materials.In chromium complexes of fused arenes-regio-and diastereoselectively accessible by ...1 Results The lecture will address aspects of functional organometallics related to the development of novel organometallic materials.In chromium complexes of fused arenes-regio-and diastereoselectively accessible by chromium-templated benzannulation of arylcarbenes by alkynes[1]-a haptotropic migration of the chromium fragment along the π-face of fused arenes is controlled by both thermodynamics and the substitution pattern of the arene and the metal coligand sphere,and can be applied towards an organo...展开更多
Since the discovery of anticancer efficacy of titanocene dichloride （Cp<sub>2</sub>TiCl<sub>2</sub>, TDC） by Koepf in 1979, the study of antitumor properties of metallocene complexes is one o...Since the discovery of anticancer efficacy of titanocene dichloride （Cp<sub>2</sub>TiCl<sub>2</sub>, TDC） by Koepf in 1979, the study of antitumor properties of metallocene complexes is one of the most active subjects after that of cisplatin in this field. Being highly active against展开更多
With the discovery of antitumor efficacy of cis-diamminedichloroplatinum（Ⅱ）（cisplatin）, intense studies searching for other inorganic and organometallicantitumor agents have been developed. It has been reported t...With the discovery of antitumor efficacy of cis-diamminedichloroplatinum（Ⅱ）（cisplatin）, intense studies searching for other inorganic and organometallicantitumor agents have been developed. It has been reported that titanocenedichlorides （Cp<sub>2</sub>TiCl<sub>2</sub>,TDC） are highly active agents against a wide spectrum ofmurine and human tumors. Biological studies show that DNA is the primary cellu-展开更多
A new mono-substituted titanocene,(η~5-cyclopentadienyl)[η~5-(1-(4-methoxyphenyl)cyclohexyl) cyclopentadienyl]dichlorotitanium(I),has been prepared via a novel modified synthesis,and its X-ray crystal structure has ...A new mono-substituted titanocene,(η~5-cyclopentadienyl)[η~5-(1-(4-methoxyphenyl)cyclohexyl) cyclopentadienyl]dichlorotitanium(I),has been prepared via a novel modified synthesis,and its X-ray crystal structure has been determined.It crystallizes in the orthorhombic space group P2_12_12_1 with cell constants a=0.9680(5)nm,b=1.2846(5)nm,c=1.6944(6)nm,Z=4,R=0.066.The I/methylaluminoxane(MAO)catalyst system produces at different polymerization temperatures either an isotactic or a syndiotactic polypropylene, both of which have the combined influence of enantiomorphic-site control and chain-end control,or an atactic polypropylene controlled by Bernoallian propagation mechanism.展开更多
Titanocene alanine complex, Cp2Ti(O2CCH(CH3)NH3+Cl-)(2), has been found to have in vitro antitumor activity against Ehrlich ascites tumor cells. Study of the interaction between Cp2Ti(O2CCH(CH3)NH3+Cl-)(2) and DNA by ...Titanocene alanine complex, Cp2Ti(O2CCH(CH3)NH3+Cl-)(2), has been found to have in vitro antitumor activity against Ehrlich ascites tumor cells. Study of the interaction between Cp2Ti(O2CCH(CH3)NH3+Cl-)(2) and DNA by UV-VIS spectra, fluorescence spectra, agarose gel electrophoresis reveals that Cp2Ti(O2CCH(CH3)NH3+Cl-)(2) forms a stable compound with DNA in molar ratio 1:1 and reduces the migration rate of ccc-DNA band and oc-DNA band. However, unlike cisplatin, the complex does not induce nicking of DNA even after a long incubation at a high ratio of the complex to DNA. The results suggest that titanocene-based antitumor agents have different mechanism of action from cisplatin-like antitumor agents.展开更多
文摘The chloromethylation reaction of substituted titanocenes (η~5-C_5H_5)(η~5-C_5H_4CRR'C_6H_4X)TiCl2 1 in the presence of polyformaldehyde and dry hydrogen chloride isreported.
文摘Seven new binuclear titanocenes with different linking bridges, unsubstituted or substituted on the Cp rings, were synthesized and tested for their effect on ethylene polymerization in the presence of MAO. The polyethylenes thus obtained had broad MWD or even bimodal GPC curves, as compared with that from two reference mononuclear titanocenes. This is explained by the difference in degree of steric hindrance around the active center sites imposed by the bulky substituted ligands assuming different configurations in the rotation of the catalyst molecules. Lower polymerization temperatures alleviate the effect of these configuration differences, as reflected in change in MW and (M) over bar(w)/(M) over bar(n). This effect is not caused by decomposition or disproportionation of the binuclear titanocenes as evidenced by the stability of the catalyst.
基金Supported by the Educational Com mittee of L iaoning Province
文摘The effects of the substituents on the cyclopentadienyl ring and the reducing agents on the catalytic activity and the stability of titanocene/NaH or n BuLi systems for the hydrogenation of olefins were investigated. For the catalyst systems composed of titanocene/NaH or n BuLi, the nature and the number of the substituents on the cyclopentadienyl ring control the catalytic behavior of those two systems. The effect of the reducing agent on the catalytic activity is relatively small. In addition, the characters of the hydrogenation of various olefins catalyzed respectively by Cp 2TiCl 2/NaH or n BuLi systems were compared.
文摘Cyclopentadienyl)[η￣5- (1-(4-methoxyphenyl)cyclohexyl)-cyclopentadienyl]titanium dichloride has been synthesized through a novel modified reaction route. The molecular structure of the title complex was determined by single-crystal Xray diffraction. Crystallographic data: C_(23)H_(26)Ocl_2Ti· 0. 3C_6H_(14),M_r=462. 44, triclinic, P1, a=11. 704(2) , b= 16. 340(4) , C=6. 824(1), a=90. 51(2) , β= 106. 98(1), γ=69. 82(2)°, V= 1165. 4(4) , Z=2, D_c= 1. 317 g/cm￣3, μ(MoKa) = 6. 2cm￣(-1), F(000) = 486 , and the final R= 0. 059 and R_w= 0. 085 for 2723 observed reflections with I>3σ(I). The cyclopentadienyl ring is symmetrically bonded to Ti(Ti-C distances 2. 361 (5)～2. 386 (5)) but the substituted cyclopentadienyl ring is asymmetrically bonded (Ti C2. 327 (4)～2. 438 (4)). The solvent petroleum-ether is disordered in the crystal.
文摘Reduction of diaryldiselenides by the system of Cp2TiCl2/Bu'MgBr/THF gave the nucleophilic arylselenium complex. They reacted with diaryl iodonium salts to afford unsymmetrical diaryl selenides in high yields.
基金Project 29672008 was supported by NationalNatural Science Foundation of China.
文摘The diaryldiselenides reacted with titanocene hydried （Cp2TiH） generted from Cp2TiCl2/i-BuMgBr to give arylselenium complexes of titanocene. They reacted readily with diaryliodoiums salt to give unsymmetical diarylselenides.
基金Supported by the National Natural Science Foundation of China.
文摘The FT-IR and FT-Raman spectra of complexes (C5H5)2TiCl2(Ⅰ), (C5H4Me)2TiCl2 (Ⅱ) and (C5HMe4)2TiCl2(Ⅲ) have been obtained and discussed. The FT-Raman spectral data pro- vide some new vibrational information about complexes (Ⅰ), (Ⅱ) and (Ⅲ). The assignments of cyclopentadienyl vibrational modes and skeletal vibrational modes have been made.
文摘Eight comptexes (RC_5H_4)_2Ti(O_2CA_r)_2(R=H,CH_3;Ar= with 2 equiv.N_aO_2CA_r.The carboxytate ligands in the complexes coordinate to titan^um atom in monodentate mode.(CH_3C_5H_4)_2Ti(O_2CC_4H_3S-2)_2 has four-coordinate bent titanocene in which the thiophencarboxyaltes are a monodeotate ligand(Ti-0=1.981(8)A,1.926(3)A;) 0-Ti-0:91.6(8)~ ; Ti-C:2.333-2.440A).
文摘1 Results The lecture will address aspects of functional organometallics related to the development of novel organometallic materials.In chromium complexes of fused arenes-regio-and diastereoselectively accessible by chromium-templated benzannulation of arylcarbenes by alkynes[1]-a haptotropic migration of the chromium fragment along the π-face of fused arenes is controlled by both thermodynamics and the substitution pattern of the arene and the metal coligand sphere,and can be applied towards an organo...
基金Project supported by the National Natural Science Foundation of Chinaby the Youth Science Foundation of Shanxi Province.
文摘Since the discovery of anticancer efficacy of titanocene dichloride （Cp<sub>2</sub>TiCl<sub>2</sub>, TDC） by Koepf in 1979, the study of antitumor properties of metallocene complexes is one of the most active subjects after that of cisplatin in this field. Being highly active against
文摘With the discovery of antitumor efficacy of cis-diamminedichloroplatinum（Ⅱ）（cisplatin）, intense studies searching for other inorganic and organometallicantitumor agents have been developed. It has been reported that titanocenedichlorides （Cp<sub>2</sub>TiCl<sub>2</sub>,TDC） are highly active agents against a wide spectrum ofmurine and human tumors. Biological studies show that DNA is the primary cellu-
基金the National Natural Science Foundation of China.
文摘A new mono-substituted titanocene,(η~5-cyclopentadienyl)[η~5-(1-(4-methoxyphenyl)cyclohexyl) cyclopentadienyl]dichlorotitanium(I),has been prepared via a novel modified synthesis,and its X-ray crystal structure has been determined.It crystallizes in the orthorhombic space group P2_12_12_1 with cell constants a=0.9680(5)nm,b=1.2846(5)nm,c=1.6944(6)nm,Z=4,R=0.066.The I/methylaluminoxane(MAO)catalyst system produces at different polymerization temperatures either an isotactic or a syndiotactic polypropylene, both of which have the combined influence of enantiomorphic-site control and chain-end control,or an atactic polypropylene controlled by Bernoallian propagation mechanism.
文摘Titanocene alanine complex, Cp2Ti(O2CCH(CH3)NH3+Cl-)(2), has been found to have in vitro antitumor activity against Ehrlich ascites tumor cells. Study of the interaction between Cp2Ti(O2CCH(CH3)NH3+Cl-)(2) and DNA by UV-VIS spectra, fluorescence spectra, agarose gel electrophoresis reveals that Cp2Ti(O2CCH(CH3)NH3+Cl-)(2) forms a stable compound with DNA in molar ratio 1:1 and reduces the migration rate of ccc-DNA band and oc-DNA band. However, unlike cisplatin, the complex does not induce nicking of DNA even after a long incubation at a high ratio of the complex to DNA. The results suggest that titanocene-based antitumor agents have different mechanism of action from cisplatin-like antitumor agents.
