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1.
Eleven borosiloxane [R′Si(ORBO)3SiR′] compounds where R′ = But and R = Ph (1), 4-PhC6H4 (2), 4-ButC6H4 (3), 3-NO2C6H4 (4), 4-CH(O)C6H4 (5), CpFeC5H4 (6), 4-C(O)CH3C6H4 (7), 4-ClC6H4 (8), 2,4-F2C6H3 (9), and R′ = cyclo-C6H11 and R = Ph (10), and 4-BrC6H4 (11) have been synthesized and characterized by spectroscopic (IR, NMR), mass spectrometric and, for compounds where R′ = But and R = 4-PhC6H4 (2), 4-ButC6H4 (3), 3-NO2C6H4 (4), CpFeC5H4 (6) and 2,4-F2C6H3 (9), X-ray diffraction studies. These compounds contain trigonal planar RBO2 and tetrahedral R′SiO3 units located around 11-atom “spherical” Si2O6B3 cores. The dimensions of the Si2O6B3 cores in compounds 2, 3, 4, 6 and 9 are remarkably similar. The reaction between [ButSi{O(PhB)O}3SiBut] (1), and excess pyridine yields the 1:1 adduct [ButSi{O(PhB)O}SiBut]. NC5H5 (12) while the reaction between 1 and N,N,N′,N′-tetramethylethylenediamine in equimolar amounts affords a 2:1 borosiloxane:amine adduct [ButSi{O(PhB)O}3SiBut]2 · Me2NCH2CH2NMe2 (13). Compounds 12 and 13 were characterised with IR and (1H, 13C and11B) NMR spectroscopies and the structure of the pyridine complex 12 was determined with X-ray techniques.  相似文献   

2.
The ansa-bis(cyclopentadiene) compounds, Me2Si(C5HPh4)(C5H4R) (R = H (2); But (3)), have been prepared by the reaction of C5HPh4(SiMe2Cl) (1) with Na(C5H5) or Li(C5H4But), respectively, and transformed to the di-lithium derivatives, Li2{Me2Si(C5Ph4)(C5H3R)} (R = H (4); But (5)), by the action of n-butyllithium. The ansa-zirconocene complexes, [Zr{Me2Si(η5-C5Ph4)(η5-C5H3R)}Cl2] (R = H (6); But (7)), were synthesized from the reaction of ZrCl4 with 4 or 5, respectively. Compounds 6 and 7 have been tested in the polymerization of ethylene and compared with their methyl-substituted analogues, [Zr{Me2Si(η5-C5Me4)(η5-C5H3R)}Cl2] (R = H (8); But (9)). Whilst 8 and 9 are catalytically active, the tetraphenyl-substituted complexes 6 and 7 proved to be inactive in the polymerization of ethylene. This phenomenon has been explained by DFT calculations based on the reaction intermediates in the polymerization processes involving 6 and 7, which showed that the extraction of a methyl group from the zirconocene complex to form the cationic active specie is endothermic and therefore unfavourable.  相似文献   

3.
Chiral “P-N-P” ligands, (C20H12O2)PN(R)PY2 [R = CHMe2, Y = C6H5 (1), OC6H5 (2), OC6H4-4-Me (3), OC6H4-4-OMe (4) or OC6H4-4-tBu (5)] bearing the axially chiral 1,1′-binaphthyl-2,2′-dioxy moiety have been synthesised. Palladium allyl chemistry of two of these chiral ligands (1 and 2) has been investigated. The structures of isomeric η3-allyl palladium complexes, (R′ = Me or Ph; Y = C6H5 or OC6H5) have been elucidated by high field two-dimensional NMR spectroscopy. The solid state structure of [Pd(η3-1,3-Ph2-C3H3){κ2-(racemic)-(C20H12O2)PN(CHMe2)PPh2}](PF6) has been determined by X-ray crystallography. Preliminary investigations show that the diphosphazanes, 1 and 2 function as efficient auxiliary ligands for catalytic allylic alkylation but give rise to only moderate levels of enantiomeric excess.  相似文献   

4.
Syntheses and crystal structures of [tBu3SbCr(CO)5] (1), [tBu3BiM(CO)5] [M = Cr (2), W (3)] and [tBu3BiMnCp′(CO)2] (4) (Cp′ = η5-C5H4CH3) are reported.  相似文献   

5.
The dialkyl complexes, (R = Pri, R′ = Me (2a), CH2Ph (3a); R = Bun, R′ = Me (2b), CH2Ph (3b); R = But, R′ = Me (2c), CH2Ph (3c); R = Ph, R′ = Me (2d), CH2Ph (3d)), have been synthesized by the reaction of the ansa-metallocene dichloride complex, [Zr{R(H)C(η5-C5Me4)(η5-C5H4)}Cl2] (R = Pri (1a), Bun (1b), But (1c), Ph (1d)), and two molar equivalents of the alkyl Gringard reagent. The insertion reaction of the isocyanide reagent, CNC6H3Me2-2,6, into the zirconium-carbon σ-bond of 2 gave the corresponding η2-iminoacyl derivatives, [Zr{R(H)C(η5-C5Me4)(η5-C5H4)}{η2-MeCNC6H3Me2-2,6}Me] (R = Pri (4a), Bun (4b), But (4c), Ph (4d)). The molecular structures of 1b, 1c and 3b have been determined by single-crystal X-ray diffraction studies.  相似文献   

6.
Hexanuclear oxo titanium(IV) isopropoxide carboxylates, of the general formula [Ti6O6(OPri)6(O2CR)6] (R = But (1), CH2But (2)) and [Ti6O6(OPri)6(O2CC(CH3)2Et)6] · 0.5(C7H8) (3), have been synthesized as polycrystalline powders in order to study their thermal properties and usability as TiO2 CVD precursors. Analysis of thermogravimetric and variable temperature (VT-IR) data shows that the thermal stability of the synthesized complexes decreases as follows 3 > 2 > 1. The composition of the vapors formed during the thermolysis of 13 were qualitatively analysed with VT-IR methods and mass spectrometry (MS-EI). According to obtained results, the decomposition of 1 and 2 proceeds with a partial decomposition and the formation of a volatile and stable titanium species, sufficient for their transport in vapors. The formation of volatile titanium-containing derivatives is an important factor that decides the application of 1 and 2 as precursors in CVD experiments. The high stability of 3 causes the thermal decomposition of this complex to be observed just above 573 K, and volatile titanium-containing derivatives were not detected in vapors. These results indicate that 3 could not be used as a precursor in CVD processes.  相似文献   

7.
Syntheses of [Me3SbM(CO)5] [M = Cr (1), W (2)], [Me3BiM(CO)5] [M = Cr (3), W (4)], cis-[(Me3Sb)2Mo(CO)4] (5), [tBu3BiFe(CO)4] (6), crystal structures of 1-6 and DFT studies of 1-4 are reported.  相似文献   

8.
The organo-tin compounds, Me2Sn(C5H4R-1)2 (R = Me (1), Pri (2), But (3), SiMe3 (4)) and Me2Sn(C5Me4R-1)2 (R = H (5), SiMe3 (6)), were prepared by the reaction of Me2SnCl2 with the lithium or sodium derivative of the corresponding cyclopentadiene. Compounds 1-6 have been characterized by multinuclear NMR spectroscopy (1H, 13C, 119Sn). In addition the molecular structures of 5 and 6 were determined by single crystal X-ray diffraction studies. The transmetalation reaction of 1-6 with ZrCl4 or [NbCl4(THF)2] gave the corresponding metallocene complexes in high yields.  相似文献   

9.
A number of bridged half-sandwich titanium complexes [η51-2-C5H4CHPh-4-R1-6-R2C6H2O]TiCl2 [R1 = H (5), Me (6), tBu (78); R2 = H (67), tBu (58)] were synthesized from the reaction of their corresponding trimethylsilyl substituted ligand precursors 2-Me3SiC5H4CHPh-4-R1-6-R2C6H2OSiMe3 [R1 = H (1), Me (2), tBu (34); R2 = H (23), tBu (14)] with TiCl4 in hexane. All new complexes were characterized by 1H and 13C NMR spectroscopy. Molecular structures of complexes 5 and 8 were determined by single crystal X-ray diffraction analysis. Upon activation with AliBu3/Ph3CB (C6F5)4, complexes 5-8 exhibit reasonable catalytic activity for ethylene polymerization and copolymerization with 1-hexene, producing polyethylene and poly(ethylene-co-1-hexene) with moderate molecular weights.  相似文献   

10.
Amination of 1-bromo-2-methylpyridine with trans-1,2-diaminocyclohexane gives the corresponding bis(aminopyridine) H2L1. Conversion of the same diamine to the N,N′-bis(amino-4,4-dimethylthiazoline) H2L2 is also completed in three steps. The analogous aminooxazoline is however inaccessible, although the aminocyclohexane analogue is prepared readily. The proligand H2L1 forms bis(aminopyridinato) alkyl complexes of the type [ZrL1R2] (R = CH2Ph, CH2But). The molecular structure of the neopentyl complex shows that the chiral backbone leads to a puckering of the N4Zr coordination sphere, which contrasts with the related cyclohexyl-bridged Schiff-base complexes which are essentially planar. [ZrL2(CH2But)2] - the first aminothiazolinato complex - is formed similarly. A comparison of the structures of [ZrL1(CH2But)2] and [ZrL2(CH2But)2] indicates that the latter has a fully delocalised N-C-N system, rather similar to a bis(amidinate). Reaction of H2L2 with [Ti(NMe2)4] gives [TiL2(NMe2)2] which appears to be C2-symmetric like the above complexes according to NMR spectra, but has one uncoordinated thiazoline unit in the solid state. This is a result of increased ring strain at the smaller titanium metal centre.  相似文献   

11.
A series of titanocene(III) alkoxides L2Ti(III)OR where L = Cp, R = Et(1b), tBu(1a), 2,6-Me2C6H3(1c), 2,6-tBu2-4-Me-C6H2(1d), or L = Cp*, R = Me(2e), tBu(2a), Ph(2f) was synthesized and subjected to reaction with [CpM(CO)3]2 [M = Mo, W], [CpRu(CO)2]2, and Co2(CO)8. The Ti(III) precursors 1a, 1c, 2a, 2e, and 2f reacted with [CpM(CO)3]2 [M = Mo, W] to form heterobimetallic complexes L2Ti(OR)(μ-OC)(CO)2MCp [M = Mo, W], of which Ti and M are linked by an isocarbonyl bridge. Reactions of these Ti(III) complexes with Co2(CO)8 resulted in formation of Ti-Co1 heterobimetallic complexes, from 2a, 2e, or 2f, or Ti-Co3 tetrametallic complexes, Cp2Ti(OtBu)(μ-OC)Co3(CO)9 from 1a, 1b, or 1c. The products were characterized by NMR, IR, and X-ray crystallography. Reaction mechanisms were proposed from these results, in particular, from steric/electronic effects of titanium alkoxides.  相似文献   

12.
A series of new compounds containing rare earth cations (Eu to Yb) and paramagnetic cluster anion [Re6Te8(CN)6]3− was prepared and investigated. The X-ray structural analyses have revealed that the compounds [{Ln(H2O)4}{Re6Te8(CN)6}] · 2.5H2O; Ln = Eu (1), Tb (3), Dy (4), Ho (5), Er (6), Tm (7), [{Gd(H2O)3}{Re6Te8(CN)6}] · 2.5H2O (2) and [{Yb(H2O)4}{Re6Te8(CN)6}] (8) are three-dimensional polymers based on Re–CN–Ln interactions. Measurements of magnetic susceptibility for 2 and 5 showed that effective magnetic moment (at 300 K) was 8.13 μB for compound 2 and 10.79 μB for compound 5 with weak antiferromagnetic ordering appeared at low temperatures.  相似文献   

13.
The Sn(IV) butyl complexes [BunSnCl3 − n(NCN)] (NCN = [C6H3(CH2NMe2)2-2,6], n = 1 (1), 2 (2), 3 (3)) were prepared. Spectroscopic analysis of 1-3 by 1H and 119Sn NMR gave evidence for the presence of intramolecular N → Sn interactions in solution. The molecular structure of 1, as determined by a single-crystal X-ray diffraction study, revealed that it contained a six-coordinate Sn(IV) center with intramolecular N → Sn coordination of both ortho-amine substituents. Addition of SnCl4 to 1 resulted in the isolation of the HCl adduct [BuSnCl3(NCN+H)] (6). Reactions of 2 and 3 with SnCl4 each resulted in the HCl salt [SnCl4(NCN+H)] (8) and the corresponding butyltin chloride, Bu2SnCl2 and Bu3SnCl, respectively. The formation of HCl adducts 6 and 8 was ascribed to transfer of the NCN ligand to SnCl4 and the presence of HCl (from partial hydrolysis of the product or SnCl4 during the work up procedure). The molecular structures of 6 and 8 have been determined through single-crystal X-ray diffraction and revealed the presence of a [BuSnCl3(aryl)] or [SnCl4(aryl)] stannate anion, respectively, with in each case one coordinated ortho-amine function and one protonated amine moiety involved in N-H?Cl-Sn hydrogen bonding in both compounds (2.14 Å for 6 and 2.18 Å for 8).  相似文献   

14.
Three monochlorotitanium complexes Cp′Ti(2,4-tBu2-6-(CPh2O)C6H2O)Cl [Cp′ = η5-C5H5 (2), η5-C5(CH3)5 (3), η5-C5H2Ph2CH3 (4)] have been synthesized in high yields (>90%) by the reaction of corresponding Cp′TiCl3 with the dilithium salt of ligand 2,4-tBu2-6-(CPh2OH)C6H2OH (1). When activated by [Ph3C]+[B(C6F5)4] and AliBu3, complexes 24 exhibit reasonable catalytic activity for ethylene polymerization, producing polyethylenes with moderate molecular weights and melting points. Addition of excess water to complex 2 gave the oxo-bridged complex [Ti(η5-C5H5)(2,4-tBu2-6-(CPh2O)C6H2O)]2O (5). Complexes 4 and 5 were characterized by single crystal X-ray diffraction.  相似文献   

15.
Two types of pyrazole-based palladium complexes were used to catalyze the polymerization of phenylacetylene. Catalysts with electron-withdrawing linkers, [{1,3-(3,5-R2pzCO)2C6H4}Pd2Cl2(μ-Cl)2] (R = tBu (1), Ph (2), Me (3), [{2,6-(3,5-R2pzCO)2C5H3N)}PdCl2] (R = tBu (4), Me (5)), show high conversion; whilst those with simple pyrazole ligands, [(3,5-R2pz)2PdCl2] (R = H (6), Me (7), tBu (8)), [(3,5-tBu2pz)2PdCl(Me)] (9), have much lower conversions. Conversion greatly improved when 9 was used to catalyze the co-polymerization of sulfur dioxide and phenylacetylene. Both types of catalysts produce predominantly transcisoidal polyphenylacetylene.  相似文献   

16.
The chemistry of η3-allyl palladium complexes of the diphosphazane ligands, X2PN(Me)PX2 [X = OC6H5 (1) or OC6H3Me2-2,6 (2)] has been investigated.The reactions of the phenoxy derivative, (PhO)2PN(Me)P(OPh)2 with [Pd(η3-1,3-R′,R″-C3H3)(μ-Cl)]2 (R′ = R″ = H or Me; R′ = H, R″ = Me) give exclusively the palladium dimer, [Pd2{μ-(PhO)2PN(Me)P(OPh)2}2Cl2] (3); however, the analogous reaction with [Pd(η3-1,3-R′,R″-C3H3)(μ-Cl)]2 (R′ = R″ = Ph) gives the palladium dimer and the allyl palladium complex [Pd(η3-1,3-R′,R″-C3H3)(1)](PF6) (R′ = R″ = Ph) (4). On the other hand, the 2,6-dimethylphenoxy substituted derivative 2 reacts with (allyl) palladium chloro dimers to give stable allyl palladium complexes, [Pd(η3-1,3-R′,R″-C3H3)(2)](PF6) [R′ = R″ = H (5), Me (7) or Ph (8); R′ = H, R″ = Me (6)].Detailed NMR studies reveal that the complexes 6 and 7 exist as a mixture of isomers in solution; the relatively less favourable isomer, anti-[Pd(η3-1-Me-C3H4)(2)](PF6) (6b) and syn/anti-[Pd(η3-1,3-Me2-C3H3)(2)](PF6) (7b) are present to the extent of 25% and 40%, respectively. This result can be explained on the basis of the steric congestion around the donor phosphorus atoms in 2. The structures of four complexes (4, 5, 7a and 8) have been determined by X-ray crystallography; only one isomer is observed in the solid state in each case.  相似文献   

17.
The synthesis, characterization and reactivity of ytterbium monochloride supported by tridentate Schiff base ligands are described. The metathesis reaction of anhydrous YbCl3 with 1 equivalent of the sodium salt of a Schiff base, [{LNa(THF)}2] (1) [LH = 3,5-But2-2-(OH)-C6H2CHN-8-C9H6N], gave the ytterbium Schiff base monochloride complex L2YbCl (2). Complex 2 reacted with NaOAr (OAr = OC6H3But-2-Me-4) in a 1:1 molar ratio to form the desired aryloxo derivative L2Yb(OAr) (3). Complex 3 can also be prepared by the one-pot reaction of the Schiff base HL, n-BuLi, YbCl3 and NaOAr in a 2:2:1:1 molar ratio. However, an unprecedented ytterbium aryloxide LL′Yb(OAr) (4) (L′ = 3,5-But2-2-(O)C6H2CH(C4H9)-NH-8-C9H6N) can be isolated in low yield as a byproduct in the later case. Reaction of complex 2 with 1 equivalent of (CH2CH-CH2)MgBr in THF afforded the unexpected complex [Mg(H2N-8-C9H6N)Cl(THF)3]Br (5). Complexes 2-5 were fully characterized by elemental analysis and X-ray diffraction.  相似文献   

18.
The synthesis, derivatization and coordination behavior of a new aminobis(diphosphonite), PhN{P(OC6H4OMe-o)2}2 (1) is described. The ligand 1 reacts with H2O2, elemental sulfur or selenium to give the corresponding dichalcogenides PhN{P(E)(OC6H4OMe-o)2}2 (E = O, 2; S, 3; Se, 4) in good yield. Reactions of 1 with Mo(CO)6, Pd(NCCH3)2Cl2 and Pt(COD)Cl2 resulted in the formation of the chelate complexes, Mo(CO)4[PhN{P(OC6H4OMe-o)2}2] (5) and MCl2[PhN{P(OC6H4OMe-o)2}2] (M = Pd,7; M = Pt, 8) whereas in the reaction of 1 with [CpFe(CO)2]2, one of the P-N bonds cleaves due to the metal assisted hydrolysis to give a mononuclear complex, [CpFe(CO){P(O)(OC6H4OMe-o)2}{PhN(H)(P(OC6H4OMe-o)2)}] (6). The molecular structures of 1, 4, 5 and 6 are determined by X-ray studies.  相似文献   

19.
Copper(I) complexes of short-bite aminobis(phosphonite), PhN{P(–OC10H6(μ-S)C10H6O–)}2 (1) have been synthesized. Reactions of 1 with an excess of CuX (X = Cl, Br, and I) afforded the ligand-bridged binuclear complexes, [PhN(PR-κP)2{Cu(μ-X)(MeCN)}2] (2, X = Cl; 3, X = Br; 4, X = I; R = –OC10H6(μ-S)C10H6O–), whereas treatment with 0.5 equiv. of [Cu(MeCN)4]PF6 produces the mononuclear bischelated cationic complex, [{PhN(PR-κP)2}2Cu](PF6) (5). Single crystal X-ray structures of complexes 3 and 4 are reported. Complex 3 shows strong π–π stacking interactions between the naphthyl moieties, whereas complex 4 shows ligand-supported Cu?Cu metallophilic interactions.  相似文献   

20.
The aldehydic benzyl ethers PhCH2OC6H4CHO (2; a/b = para/meta series) are readily available from the corresponding phenols and react with Wittig reagents derived from [Ph3PCH2CH2Rf8]+I (Rf8=(CF2)7CF3) to give PhCH2OC6H4CHCHCH2Rf8 (86-93%, Z major). Reactions with H2 over Pd/C give the fluorous phenols HOC6H4(CH2)3Rf8(4a,b; 87-91%). Condensations with PCl3 and NEt3 (3.0:1.0:3.3 mol ratio) give the fluorous phosphites P[OC6H4(CH2)3Rf8]3(5a,b; 92-94%), but traces of 4a,b are difficult to remove. The phthalate-based benzyl ethers PhCH2OC6H3(COOR)2 (7; ,5/3,4 OC6H3-3,n-(R)2 series) are easily accessed and reduced with LiAlH4 to the diols PhCH2OC6H3(CH2OH)2(8c,d; 89-90%). Diol 8c and the Dess-Martin periodinane react to give the dialdehyde PhCH2OC6H3(CHO)2 (9c; 95%). This is elaborated by a sequence analogous to 2→4→5 to the fluorous phenol HOC6H3((CH2)3Rf8)2 (11c; 97%/96%, two steps) and phosphite P[OC6H3((CH2)3Rf8)2]3 (12c, 92%), from which traces of 11c are difficult to remove. Diol 8d can be similarly elaborated to 11d, but the dialdehyde 9d is labile and the combined yield of the Dess-Martin/Wittig steps is 32%. The CF3C6F11/toluene partition coefficients of 11c,d, and 12c (two pony tails; 70:30, 72:28, 92:8) are much higher than those of 4a and b (one pony tail; 12:88, 14:86).  相似文献   

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