多吡唑烷配合物研究进展

描述了双吡唑烷及其三吡唑甲烷配体的合成,详细地综述了它们在无机配位化学及金属有机等方面近年来的研究进展。     

含吡唑配体的VIB金属羰基配合物的合成与电化学性质研究

研究了吡唑类配体与M(CO)6(M=Cr,W)的光化学反应,合成了一系列的含吡唑配体的五羰基铬钨配合物。研究了该类化合物的电化学性质。结果表明：铬系列化合物存在一对准可逆的氧化还原峰,而钨系列化合物只存在一个不可逆的氧化峰,用X射线单晶衍射测定了化合物3,4,5－三甲基吡唑五羰基铬的晶体结构。该晶体为单斜晶系,空间群为P2(1)/m,晶胞参数为a=0.9106(3)nm,b=07627(2)nm,c=0.9637(3)nm,β＝91.855(5)°,V=0.6689(3)nm^3,Z=2,R=0.042,Cr为六配位的变形八面体构型。     

锡钼(钨)异多核金属配合物研究进展

描述了锡钼(钨)异多核金属配合物近年来的研究进展.根据中心金属锡及钼(钨)周围配体的不同,该类配合物表现出不同的结构特征和反应活性.     

蝎型螯合配合和在生物功能分子模拟方面的应用

蝎型螯合配合物结构新颖、功能齐全。本文概述了它在模拟碳酸酐酶，亚硝酸盐还原酶和血蓝蛋白方面的应用。     

对苯二甲酰双环戊烯基锡钼（钨）异多核金属配合物的合成与晶体结构

通过对苯二甲酰双环戊二烯基三羰基钼（钨）负离子与有机锡的反应，合成了 一系列的对苯二甲酰双环戊二烯基锡钼（钨）异多核金属配合物，并用IR，~1H NMR和元素分析对其进行了表征。结果表明，环戊二烯上的拉电子取代基极大地减 弱金属负离子的亲核性，对苯二甲酰双环戊二烯基三羰基钼（钨）负离子与 R_2SnCl_2(R = Ph, Me, Et)反应时，仅有一个氯原子被金属负离子所取代。用X射 线单晶衍射测定了化合物{p-[(Ph_3Sn)(CO)_3MoC_5H_4-C(O)]_2C_6H_4}的晶体结 构。该晶体为单斜晶系，空间群为C2/c，晶胞参数为：a = 3.4209(10) nm, b = 1.1329(3) nm, c = 1.4214(4) nm, β = 104.466(5) °, V = 5.334(3) nm~3, Z = 4, R = 0.033。两个SnMo结构单元处于桥连苯基的反位。     

对苯二甲酰双环戊烯基锡钼（钨）异多核金属配合物的合成与晶体结构

通过对苯二甲酰双环戊二烯基三羰基钼（钨）负离子与有机锡的反应,合成了 一系列的对苯二甲酰双环戊二烯基锡钼（钨）异多核金属配合物,并用IR,~1H NMR和元素分析对其进行了表征。结果表明,环戊二烯上的拉电子取代基极大地减 弱金属负离子的亲核性,对苯二甲酰双环戊二烯基三羰基钼（钨）负离子与 R_2SnCl_2(R = Ph, Me, Et)反应时,仅有一个氯原子被金属负离子所取代。用X射 线单晶衍射测定了化合物{p-[(Ph_3Sn)(CO)_3MoC_5H_4-C(O)]_2C_6H_4}的晶体结 构。该晶体为单斜晶系,空间群为C2/c,晶胞参数为：a = 3.4209(10) nm, b = 1.1329(3) nm, c = 1.4214(4) nm, β = 104.466(5) °, V = 5.334(3) nm~3, Z = 4, R = 0.033。两个SnMo结构单元处于桥连苯基的反位。     

稀土配合物研究 II: 1,6-双(1'-苯基-3'-甲基-5'-氧代吡唑-4'-基)-1,6-己二酮与钐(III)、铕(III)、铽(III)、镝(III)固体配合物的合成及性质研究

本文合成了1,6-双(1'-苯基-3'-甲基-5'-氧代吡唑-4'-基)-1,6-己二酮与Sm(III),Eu(III), Tb(III), Dy(III)的固体配合物, 并对他们的某些性质进行了研究.     

meso-四(对烷氧苯基)卟啉金属配合物的合成和性能研究(II)

合成了Zn、Pb两个系列卟啉金属配合物12个,其中6个为未见文献报道的新化合物,用元素分析、IR、UV、^1HNMR、MS确证了其结构。总结了Zn、Pb与卟啉类配体配合的IR、UV、^1HNMR判据。研究了这两个系列化合物的液晶性能,发现9个化合物具有液晶性。     

蝎型螯合配合物在生物功能分子模拟方面的应用

蝎型螯合配合物结构新颖，功能齐全。本文概述了它在模拟碳酸酐酶，亚硝酸盐还原酶和血蓝蛋白方面的应用。     

稀土配合物研究 II: 1,6-双(1'-苯基-3'-甲基-5'-氧代吡唑-4'-基)-1,6-己二酮与钐(III)、铕(III)、铽(III)、镝(III)固体配合物的合成及性质研究

本文合成了1,6-双(1'-苯基-3'-甲基-5'-氧代吡唑-4'-基)-1,6-己二酮与Sm(III),Eu(III), Tb(III), Dy(III)的固体配合物, 并对他们的某些性质进行了研究.     

Mononuclear and binuclear sandwich copper(II) complexes with poly(pyrazolyl)borate ligands: syntheses, structures and properties

A series of Cu(II) complexes Cu(2)[micro-pz](2)[HB(pz)(3)](2) (1), Cu[H(2)B(pz)(2)](2) (2), Cu[HB(pz)(3)](2) (3), Cu[HB(pz(Me2))(3)](2) (4), Cu[B(pz)(4)](2) (5) (pz=pyrazole), have been synthesized and characterized by elemental analysis, IR, UV-vis, X-ray diffraction, thermal analysis and theoretical analysis. The IR spectra give the Cu-N vibration modes at 322, 366, 344, 387, and 380 cm(-1) in complexes 1-5, respectively. The UV spectra show all the complexes have same UV absorption at 232 nm; there is another band at 332 nm for complexes 1, 2 and 4, while for complexes 3 and 5, the bands are at 272 and 308 nm, respectively. Complex 1 has a binuclear structure in which two pyrazole ligands bridge two Cu-Tp units. In 2-5, the Cu(II) centers are coordinated with dihydrobis(pyrazolyl)borate (Bp), hydrotris(pyrazolyl)borate (Tp), hydrotris(3,5-Me2pyrazolyl)borate (Tp'), tetrakis(pyrazolyl)borate (Tkp) respectively to form a mononuclear structure. The results of thermal analysis for complexes 1-5 are discussed too.     

Synthesis, structural characterization, and properties of heavier alkaline earth complexes containing bis(pyrazolyl)borate or bis(3,5-diisopropylpyrazolyl)borate ligands

Treatment of a solid mixture of KBH₄ with six equivalents of 3,5-diisopropylpyrazole (iPr₂pzH) at 180 °C afforded KTp^iPr2(iPr₂PzH)₃ in 53% yield. KBp^iPr2 was synthesized in 56% yield by treatment of a 1:2 M ratio of KBH₄ and iPr₂PzH in refluxing dimethylacetamide. Treatment of MI₂ (M = Ca, Sr, Ba) with two equivalents of KBp or KBp^iPr2 in tetrahydrofuran afforded MBp₂(THF)₂ (M = Ca, 64%, M = Sr, 81%), BaBp₂(THF)₄ (32%), and M(Bp^iPr2)₂(THF)₂ (M = Ca, 63%; M = Sr, 61%, M = Ba, 48%) as colorless crystalline solids upon workup. These complexes were characterized by spectral and analytical techniques and by X-ray crystal structure determinations of all complexes except KBp^iPr2. KTp^iPr2(iPr₂PzH)₃ contains one κ³-N,N,N-Tp^iPr2 ligand and three κ¹-iPr₂pzH ligands, with overall distorted octahedral geometry about the K ion. The iPr₂PzH nitrogen-hydrogen bonds are engaged in intramolecular hydrogen bonding to the 2-nitrogen atoms of the Tp^iPr2 ligand. The solid state structures of MBp₂(THF)₂, BaBp₂(THF)₄, and M(Bp^iPr2)₂(THF)₂ contain κ³-N,N,H Bp and Bp^iPr2 ligands, which form through metal-nitrogen bond formation to the 2-nitrogen atoms of the pyrazolyl fragments and metal-hydrogen bond formation to one boron-bound hydrogen atom per Bp ligand. SrBp₂(THF)₂has the shortest metal-hydrogen interactions among the series. A combination of preparative sublimations, solid state decomposition temperatures, and thermogravimetric analysis demonstrated that MBp₂(THF)₂, BaBp₂(THF)₄, and M(Bp^iPr2)₂(THF)₂ undergo solid state decomposition at moderate temperatures.     

Synthesis and reactivity of hydride and dihydrogen complexes of ruthenium with tris(pyrazolyl)borate and phosphite ligands

Chloro phosphite complexes RuClTpL(PPh₃) (1a, 1b) [L = P(OEt)₃, PPh(OEt)₂] and RuClTp[P(OEt)₃]₂ (1c) [Tp = hydridotris(pyrazolyl)borate] were prepared by allowing RuClTp(PPh₃)₂ to react with an excess of phosphite. Treatment of the chloro complexes 1 with NaBH₄ in ethanol yielded the hydride RuHTpL(PPh₃) (2a, 2b) and RuHTp[P(OEt)₃]₂ (2c) derivatives. Protonation reaction of 2 with Brønsted acids was studied and led to thermally unstable (above 10 °C) dihydrogen [Ru(η²- H₂)TpL(PPh₃)]⁺ (3a, 3b) and [Ru(η²-H₂)Tp{P(OEt)₃}₂]⁺ (3c) complexes. The presence of the η²-H₂ ligand is indicated by short T_1 min values and J_HD measurements of the partially deuterated derivatives. Aquo [RuTp(H₂O)L(PPh₃)]BPh₄ (4), carbonyl [RuTp(CO)L(PPh₃)]BPh₄ (5), and nitrile [RuTp(CH₃CN)L(PPh₃)]BPh₄ (6) derivatives [L = P(OEt)₃] were prepared by substituting H₂ in the η²-H₂ derivatives 3. Vinylidene [RuTp{CC(H)R}L(PPh₃)]BPh₄ (7, 8) (R = Ph, ^tBu) and allenylidene [RuTp(CCCR1R2)L(PPh₃)]BPh₄ (9-11) complexes (R1 = R2 = Ph, R1 = Ph R2 = Me) were also prepared by allowing dihydrogen complexes 3 to react with the appropriate HCCR and HCCC(OH)R1R2 alkynes. Deprotonation of vinylidene complexes 7, 8 with NEt₃ was studied and led to acetylide Ru(CCR)TpL(PPh₃) (12, 13) derivatives. The trichlorostannyl Ru(SnCl₃)TpL(PPh₃) (14) compound was also prepared by allowing the chloro complex RuClTpL(PPh₃) to react with SnCl₂ · 2H₂O in CH₂Cl₂.     

Titanium and zirconium complexes containing sterically hindered hydrotris(pyrazolyl)borate ligands: synthesis, structural characterization, and ethylene polymerization studies

The synthesis, characterization and ethylene polymerization behavior of a set of Tp^′MCl₃ complexes (4, M=Ti, Tp^′=HB(3-neopentyl-pyrazolyl)₃⁻(Tp^Np); 5, M=Ti, Tp^′=HB(3-tert-butyl-pyrazolyl)₃⁻(Tp^tBu); 6, M = Ti, Tp^′=HB(3-phenyl-pyrazolyl)₃⁻(Tp^Ph); 7, M=Zr, Tp^′=HB(3-phenyl-pyrazolyl)₃⁻(Tp^Ph); 8, M=Zr, Tp^′ = HB(3-tert-butyl-pyrazolyl)₃⁻(Tp^tBu)) is described. Treatment of these tris(pyrazolyl)borate Group IV compounds with methylalumoxane (MAO) generates active catalysts for ethylene polymerization. For the polymerization reactions performed in toluene at 60 °C and 3 atm of ethylene pressure, the activities varied between 1.3 and 5.1 × 10³ g of PE/mol[M] · h. The highest activity is reached using more sterically open catalyst precursor 4. The viscosity-average molecular weights () of the PE’s produced with these catalyst precursors varying from 3.57 to 20.23 × 10⁵ g mol⁻¹ with melting temperatures in the range of 127-134 °C. Further polymerization studies employing 7 varying Al/Zr molar ratio and temperature of polymerization showed that the activity as well as the polymer properties are dependent on these parameters. In that case, higher activity was attained at 60 °C. The viscosity-average molecular weights of the polyethylene’s decreases with increasing Al/Zr molar ratio.     

A convenient preparative method for anionic tris(substituted pyrazolyl)methane ligands

The synthesis of tris[3-(6-carboxypyridin-2-yl)pyrazol-1-yl]methane is described in a linear multi-step protocol. The pyridyl-pyrazolyl arms are first constructed before being condensed with chloroform. Careful study of the condensation reaction shows the presence of an isomeric form of the tris(pyrazolyl)methane derivative in which one of the pyrazolyl substituents is linked through the nitrogen atom at the 2 position of the pyrazol. After acid-catalysed isomerisation to the desired isomer, the intermediate compound was subjected to a carboalkoxylation reaction and a subsequent hydrolysis. These are some rare examples of reactions directly occurring on the tris(pyrazolyl)methane platforms.     

Photochemistry of tris(pyrazolyl)borate titanium(IV) complexes

The electronic features and photochemistry of TpTiCl₃ (1) (Tp = hydrotris(pyrazol-1-yl)borate) and Tp*TiCl₃ (2) (Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate) were studied in THF. Reactive decay of the excited states produced either (or ) and metal center Ti(III) radicals via homolytic cleavage of the Tp → Ti (Tp* → Ti) bond. Cleavage of the Tp → Ti and the Tp* → Ti bond as a primary photoprocess is shown to be consistent with LMCT Tp → Ti and Tp* → Ti excitation. TpTiCl₂(THF) (3) and Tp*TiCl₂(THF) (4) were also prepared by stoichiometric reduction of 1 and 2 with Li₃N. The THF ligand in 3 and 4 was replaced by the stable nitroxyl radical TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) to provide the new complexes TpTiCl₂(TEMPO) (5) and Tp*TiCl₂(TEMPO) (6) in which the TEMPO ligand is η¹ coordinated to Ti(IV). Photolysis of 5 and 6 generate Ti(III) and the TEMPO radical in the primary photochemical step.     

Syntheses and characterization of mono and dinuclear complexes of platinum group metals bearing benzene-linked bis(pyrazolyl)methane ligands

Reaction of the benzene-linked bis(pyrazolyl)methane ligands, 1,4-bis{bis(pyrazolyl)-methyl}benzene (L1) and 1,4-bis{bis(3-methylpyrazolyl)methyl}benzene (L2), with pentamethylcyclopentadienyl rhodium and iridium complexes [(η⁵-C₅Me₅)M(μ-Cl)Cl]₂ (M = Rh and Ir) in the presence of NH₄PF₆ results under stoichiometric control in both, mono and dinuclear complexes, [(η⁵-C₅Me₅)RhCl(L)]⁺ {L = L1 (1); L2 (2)}, [(η⁵-C₅Me₅)IrCl(L)]⁺ {L = L1 (3); L2 (4)} and [{(η⁵-C₅Me₅)RhCl}₂(μ-L)]²⁺ {L = L1 (5); L2 (6)}, [{(η⁵-C₅Me₅)IrCl}₂(μ-L)]²⁺ {L = L1 (7); L2 (8)}. In contrast, reaction of arene ruthenium complexes [(η⁶­arene)Ru(μ-Cl)Cl]₂ (arene = C₆H₆, p-ⁱPrC₆H₄Me and C₆Me₆) with the same ligands (L1 or L2) gives only the dinuclear complexes [{(η⁶-C₆H₆)RuCl}₂(μ-L)]²⁺ {L = L1 (9); L2 (10)}, [{(η⁶-p-ⁱPrC₆H₄Me)RuCl}₂(μ-L)]²⁺ {L = L1 (11); L2 (12)} and [{(η⁶-C₆Me₆)RuCl}₂(μ-L)]²⁺ {L = L1 (13); L2 (14)}. All complexes were isolated as their hexafluorophosphate salts. The single-crystal X-ray crystal structure analyses of [7](PF₆)₂, [9](PF₆)₂ and [11](PF₆)₂ reveal a typical piano-stool geometry around the metal centers with six-membered metallo-cycle in which the 1,4-bis{bis(pyrazolyl)-methyl}benzene acts as a bis-bidentate chelating ligand.     

Copper(I) complexes with fluorinated hydrotris(pyrazolyl)borate: Influence of electronic effects on their structure,physicochemical properties,and reactivity

Copper(I) coordination complexes of the anionic fluorinated ligand, hydrotris(3-trifluoromethyl-5-methyl-1-pyrazolyl)borate (L0f⁻), i.e. the copper(I) carbonyl complex, [Cu^I(L0f)(CO)] (1), the copper(I) triphenylphosphine complex, [Cu^I(L0f)(PPh₃)] (2), the copper(I) acetonitrile complex, [Cu^I(L0f)(NCMe)] (3), and the corresponding copper(I) triphenylphosphine complex with hydrotris(3,5-diisopropyl-1-pyrazolyl)-borate anion (L1⁻), i.e. [Cu^I(L1)(PPh₃)] (4), were synthesized in order to investigate the influence of the electron-withdrawing groups on the pyrazolyl rings. The structures of complexes 1, 2, and 4 were determined by X-ray crystallography. While X-ray crystallography did not show definitive trends in terms of copper(I) atom geometry, the clear influence of the electronic structure of the pyrazolyl rings is observed by spectroscopic techniques, namely, IR and multinuclear NMR spectroscopy. Finally, the relative stability of the copper(I) complexes is discussed.     

Influences of steric bulkiness in hydrotris(pyrazolyl)borate ligands on ethylene polymerization reaction

Manganese(II) complex catalysts with hydrotris(pyrazolyl)borate ligands have been examined on their catalytic performance in ethylene polymerization and ethylene/1‐hexene copolymerization. The activities of [Mn(L6)(Cl)(NCMe)] ( 1 ) and [Mn(L10)(Cl)] ( 2 ) activated by Al(i‐Bu)₃/[Ph₃C][B(C₆F₅)₄] for ethylene polymerization go up to 326 and 11 kg mol (cat^?1) h^?1, respectively, (L6^? = hydrotris(3‐phenyl‐5‐methyl‐1‐pyrazolyl)borate anion, L10^? = hydrotris(3‐adamantyl‐5‐isopropyl‐1‐pyrazolyl)borate anion). In particular, for ethylene/1‐hexene copolymerization, complex 1 gives high‐molecular‐weight poly(ethylene‐co‐1‐hexene)s with the highest M_w of 439,000 in manganese olefin polymerization catalyst systems. Moreover, the 1‐hexene incorporation by complex 1 seems more efficient than that by [Mn(L3)(Cl)] ( 4 ) (L3^? = hydrotris(3‐tertiary butyl‐5‐isopropyl‐1‐pyrazolyl)borate anion). In this work, we demonstrated that the coordination geometry and coordination number are also important factors for ethylene polymerization reaction as well as steric hindrances and ligand frameworks in our manganese(II) catalysts. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5720–5727, 2009