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1.
The new hexaalkylborazine chromium tricarbonyls (n-Pr)3B3N3Me3Cr(CO)3 (V), Me3B3N3(n-Pr)3Cr(CO)3 (VI), (i-Pr)3B3N3Me3Cr(CO)3 (VII) and Me3B3N3(i-Pr)3Cr(CO)3 (VIII) have been prepared from fac-Cr(CO)3(MeCN)3 and the corresponding borazine in dioxane or without solvent. They are much more labile than the isomeric complex Et3B3N3Et3Cr(CO)3 (IV) which can be readily obtained from Et3B3N3Me3Cr(CO)3 and Et3B3N3Et3 by ring ligand exchange. The NMR., IR., UV. and Mass spectroscopic data of the complexes IV–VIII will be briefly discussed. The preparation of the borazine derivatives (n-Pr)3B3N3Me3 (IX) and Me3B3N3(n-Pr)3 (X) is also reported.  相似文献   

2.
The surface acidity/basicity of perovskite-type mixed oxides (LaCrO3, PrCrO3, SmCrO3, LaMnO3, PrMnO3, SmMnO3, LaFeO3, PrFeO3, SmFeO3, LaCoO3, PrCoO3, SmCoO3, LaNiO3, PrNiO3 and SmNiO3) are reported. These properties have been correlated with the catalytic activity of these oxides towards esterification of acetic acid usingn-butanol.  相似文献   

3.
K3BiSe3, Rb3BiSe3, and Cs3BiSe3 – Derivatives of the Th3P4 Structure Type The compounds K3BiSe3, Rb3BiSe3, and Cs3BiSe3 were synthesized by heating mixtures of Bi2O3 and the respective alkalicarbonate in a stream of hydrogen saturated by selenium at 850°C. Thin crystals of the compounds appear red in transmitted light. They crystallize isostructural with Na3AsS3, space group P213, lattice constants a = 9.771(5) Å, a = 10.161(3) Å, and a = 10.587(5) Å for K3BiSe3, Rb3BiSe3, and Cs3BiSe3, respectively. The Na3AsS3 structure type is a derivative of the Th3P4 structure type.  相似文献   

4.
In the system LiSO3CF3/RbSO3CF3 four different quasi‐ternary phases occur: Li0.7Rb0.3SO3CF3, Li0.55Rb0.45SO3CF3, LiRb2(SO3CF3)3, and Li0.2Rb0.8SO3CF3. These have been identified, and characterized by means of X‐ray powder diffractometry and DSC. LiSO3CF3 is trimorphic, LiRb2(SO3CF3)3 is dimorphic and RbSO3CF3 exists in four different modifications. The cation dynamics has been studied using 7Li‐NMR line shape analysis and 7Li‐spin lattice relaxation (T1) measurements. The pure and mixed trifluoromethylsulfonates in the system LiSO3CF3/RbSO3CF3 are solid electrolytes. Their ionic conductivities below 475 K increase with the rubidium content. Above this temperature, the conductivity of β‐LiRb2(SO3CF3)3 exceeds the one of δ‐RbSO3CF3.  相似文献   

5.
The reactions of py‐hz ligands ( L1–L5 ) with Pb(CF3SO3)2?H2O resulted in some rare examples of discrete single‐stranded helical PbII complexes. L1 and L2 formed non‐helical mononuclear complexes [Pb L1 (CF3SO3)2]?CHCl3 and Pb L2 (CF3SO3)2][Pb L2 CF3SO3]CF3SO3?CH3CN, which reflected the high coordination number and effective saturation of PbII by the ligands. The reaction of L3 with PbII resulted in a dinuclear meso‐helicate [Pb2 L3 (CF3SO3)2Br]CF3SO3?CH3CN with a stereochemically‐active lone pair on PbII. L4 directed single‐stranded helicates with PbII, including [Pb2 L4 (CF3SO3)3]CF3SO3?CH3CN and [Pb2 L4 CF3SO3(CH3OH)2](CF3SO3)3?2 CH3OH?2 H2O. The acryloyl‐modified py‐hz ligand L5 formed helical and non‐helical complexes with PbII, including a trinuclear PbII complex [Pb3 L5 (CF3SO3)5]CF3SO3?3CH3CN?Et2O. The high denticity of the long‐stranded py‐hz ligands L4 and L5 was essential to the formation of single‐stranded helicates with PbII.  相似文献   

6.
The triphenylsiloxy-substituted cyclotriphosphazenes, N3P3Cl5OSiPh3, gem-N3P3Cl4(OSiPh3)2, N3P3(OSiPh3)6, and N3P3(OPh)5OSiPh3, have been prepared. The synthesis of gem-N3P3Cl4(OSiPh3)2 involves the reaction of (NPCl2)3 with Ph3SiONa to form the intermediates gem-N3P3Cl4(OSiPh3)2(ONa) and gem-N3P3Cl4(ONa)2, which yield gem-N3P3Cl4(OSiPh3)2 when treated with Ph3SiCl. The compounds N3P3Cl5OSiPh3 and N3P3(OSiPh3)0 are formed by the condensation reactions of N3P3Cl5OBun and N3P3(OBun)6, respectively, with Ph3SiCl. The compound N3P3(OPh)5OSiPh3 is synthesized by the reaction between N3P3(OPh)5Cl and Et3SiONa to first give the intermediate N3P3(OPh)5ONa, which yields N3P3(OPh)5OSiPh3 when reacted with Ph3SiCl. The structural characterization and properties of these compounds are discussed. The crystal and molecular structure of gem-N3P3Cl4(OSiPh3)2 has been investigated by single-crystal X-ray diffraction techniques. The crystals are monoclinic with the space group P21/c with a = 16.850(8), b = 12.829(4), c = 18.505(15) Å, and β = 101.00(6)° with V = 3927 Å3 and Z = 4. © 1996 John Wiley & Sons, Inc.  相似文献   

7.
Solvolysis of [RhMe(CF3SO3)2(Me3[9]aneN3)] ( 1 ) (Me3[9]aneN3 = 1, 4, 7‐trimethyl‐1, 4, 7‐triazacyclononane) in CH3CN, DMSO or pyrazole (L) leads to substitution of both trifluoromethylsulfonate ligands and formation of the cationic complexes [RhMeL2(Me3[9]aneN3)](CF3SO3)2 3—5 . In contrast, treatment of [RuCl3(Me3[9]aneN3)] ( 2 ) with Ag(CF3SO3) in a 1:3 ratio for 2h in CH3CN leads to formation of the tetranuclear complex [{RuCl3(Me3[9]aneN3)}2Ag2(CF3SO3)(CH3CN)](CF3SO3) · CH3CN ( 6 ) with a novel [(RuCl3)2Ag2] core. More forcing conditions enable the substitution of respectively one or two chloride ligands by CH3CN (reflux 18h) or DMF (85°C, 1h) to afford [RuCl2(CH3CN)(Me3[9]aneN3)](CF3SO3) ( 7 ) and [RuCl(DMF)2(Me3[9]aneN3)](CF3SO3)2 ( 8 ). The heteroleptic sandwich complex [Ru([9]aneS3)(Me3[9]aneN3)](CF3SO3)2 ( 9 ) can be prepared by reduction of 2 with Zn powder in acetone in the presence of 3 equiv. of Ag(CF3SO3), followed by addition of [9]aneS3 (1, 4, 7‐trithiacyclononane). The redox potential E°(Ru3+/Ru2+) of +1.87 V vs NHE for 9 is only —0.12 V lower than that of the homoleptic complex [Ru([9]aneS3)2]2+. Crystal structures are reported for 3 — 9 .  相似文献   

8.
Fluoridolysis of Cyclophosphazenes and Lineary Polyphosphazenes The fluorination of nongeminal trans P3N3Cl4(NEt2)2 and nongeminal trans P3N3Cl3(NEt2)3 with the fluorination agent Et3N · 0,6 HF ( B ) occurs under retention of configuration yielding P3N3Cl2F2(NEt2)2 and P3N3F4(NEt2)2 or P3N3F3(NEt2)3, respectively. P3N3Cl6 is nearly quantitatively converted into P3N3F6. Poly(dichlorophosphazene) reacts to a poly(difluorophosphazene), (PNF2)n, distinguished by a moderate solubility in THF.  相似文献   

9.
Using the program package from the IVTANTERMO databank, the thermodynamic properties of CH3SiH3, CCl3SiH3, SiCl3CH3, SiCl3SiH3, SiCl3CCl3, and SiCl3SiCl3 were calculated and the thermolysis process was studied for CCl3SiH3, SiCl3CCl3, and SiCl3SiCl3.  相似文献   

10.
单氢钌配合物与水和2,2,2-三氟乙醇的作用机理   总被引:1,自引:0,他引:1  
利用原位1H和31P NMR对单氢钌配合物TpRu(PPh3)(CH3CN)H [Tp=hydrotris(pyrazolyl)borate]与H2O和酸性HOCH2CF3的反应进行了研究, 结果显示相应的反应产物分别是TpRu(PPh3)(CH3CN)(OH) 和TpRu(PPh3)(CH3CN)(OCH2CF3). 观察到反应过程中Ru-H…HOH和Ru-H…HOCH2CF3分子间的氢键作用. 提出了生成TpRu(PPh3)(CH3CN)(OH)和TpRu(PPh3)(CH3CN)(OCH2CF3)的不同作用机理. 在水存在下, TpRu(PPh3)(CH3CN)H 与H2O反应, 经过中间体TpRu(PPh3)(H2O)H和TpRu(PPh3)(OH)(η2-H2)生成产物TpRu(PPh3)(CH3CN)(OH). 而TpRu(PPh3)(CH3CN)H与酸性HOCH2CF3反应时, 单氢配体被质子化形成中间体[TpRu(PPh3)(CH3CN)- (η2-H2)](OCH2CF3), 进而转变成产物TpRu(PPh3)(CH3CN)(OCH2CF3). TpRu(PPh3)(CH3CN)(OCH2CF3)与H2作用, 经中间体TpRu(PPh3)(HOCH2CF3)H生成TpRu(PPh3)(η2-H2)H.  相似文献   

11.
V(SO3CF3)3, VO(SO3CF3)2 and VO(SO3CF3)3 have been prepared by reacting V(O2CCF3)3, VO(O2CCF3)2 and VOC13 with HSO3CF3. The i.r. data suggest a bridging bidentate nature for SO3CF3 groups. The diffuse reflectance spectrum of V(SO3CF3)3 suggests hexacoordination of vanadium, whilst that of VO(SO3CF3)2 is comparable to either five or six coordinated oxovanadium (IV) systems. The magnetic moments of V(SO3CF3)3 and VO(SO3CF3)2 are slightly lower than the spin-only values. Thermal decomposition of these triflates is simple. All the three triflates form coordination complexes with pyridine, 2, 2′-bipyridyl and triphenylphosphine oxide.  相似文献   

12.
K3SbSe3, Rb3SbSe3, and Cs3SbSe3 – Synthesis and Crystal Structure The compounds K3SbSe3, Rb3SbSe3 and Cs3SbSe3 were synthesized by heating mixtures of Sb2O3 and an alkalicarbonate in a stream of hydrogen saturated by selenium in a temperature range between 750 °C and 800 °C. The compounds crystallize isostructural with Na3AsS3. A comparison of atomic distances and bond angles with those of the isostructural arsenic and bismuth compounds shows the effect of lone pairs.  相似文献   

13.
Me3B3N3H3Cr(CO)3 has been obtained by ring-ligand exchange starting from Et3B3N3Me3Cr(CO)3 and Me3B3N3H3. The new compound has been characterised by means of their IR, NMR, UV and mass spectroscopic data.  相似文献   

14.
[(Ph3Sn)3VO4]·CH3CN and [(Ph3Sn)3VO4]·2 DMF, Triphenyltin Vanadates with Novel Chain Structures The reaction of Na3VO4 with Ph3SnCl in a water/CH2Cl2 mixture leads to the formation of [(Ph3Sn)3VO4] ( 1 ). Recrystallization of 1 from toluene/CH3CN gives pale yellow crystals of [(Ph3Sn)3VO4]·CH3CN ( 2 ). 2 crystallizes as coordination polymer which consists of infinite chains composed of corner‐sharing VO4 tetrahedra and Ph3SnO2 trigonal bipyramides. Additionally the VO4 groups are connected to two terminal SnPh3‐Groups containing tin atoms in a tetrahedral environment. [(Ph3Sn)3VO4]·2 DMF ( 3 ) which is obtained from Na3VO4 and Ph3SnCl in a water/DMF mixture contains a polymeric chain structure similar to 2 and additionally one of the terminal SnPh3 groups is coordinated to a DMF solvent molecule.  相似文献   

15.
Reaction of [MnBr(CO)3L] [L = Ph2POCH2CH2OPPh2, L1 , {(CH3)2CH}2POCH2CH2OP{CH(CH3)2}2, L2 ] with AgO3SCF3 and AgO2CCF3 in dichloromethane afforded the new complexes [Mn(O3SCF3)(CO)3L] and [Mn(O2CCF3)(CO)3L], respectively. Substitution of O3SCF3 resulted in the new species [Mn(SCN)(CO)3L], [Mn(NCCH3)(CO)3L](O3SCF3) and, in the case of L2 , [Mn(CN)(CO)3L2]. By contrast, any attempt to displace the O2CCF3 ligand in the same way was unsuccessful. After maintaining for some days the complex [Mn(CH3CN)(CO)3L1](O3SCF3) in dichloromethane at room temperature, the new complex [MnCl(CO)3L1] was formed. All the new complexes were characterized by elemental analysis, mass spectrometry and IR and NMR spectroscopies. In the case of [Mn(O3SCF3)(CO)3L1], [Mn(O2CCF3) (CO)3L1], [MnCl(CO)3L1], [Mn(CH3CN) (CO)3L2] (O3SCF3), [Mn(CN)(CO)3L2] and [Mn(O2CCF3)(CO)3L2], together with the previously synthesized complex [MnBr(CO)3L2], suitable crystals for X‐ray structural analysis were isolated. In all of them the Mn atom adopts six‐coordination by bonding to the three CO ligands, the two P atoms of L and either one C atom (CN), one oxygen atom (O2CCF3, O3SCF3), one N atom (CH3CN, SCN) or the halogen atom (Cl, Br).  相似文献   

16.
Aluminium trichloride forms the adducts AlCl3 · NH2CH3, AlCl3 · 2NH2CH3, AlCl3 · 4NH2CH3; AlCl3 · NH3CH3Cl, AlCl3 · 2NH3CH3Cl. The interaction between AlCl3, PCl5 and NH3CH3Cl in the molar ratio 1:3:2 proceeds according to the reaction equation in “Inhaltsübersicht”. On applying other stoichiometric amounts, [Cl2(NHCH3)P? N(CH3)? AlCl3] · HCl and [Cl3P? N(CH3)? AlCl3] · HCl are obtained; the latter reacts as [Cl3P? NHCH3][AlCl4]. At the molar ratio AlCl3:PCl5:NH3CH3Cl = 1:2:4 a compound is formed being presumably the six-membered heterocycle formulated in “Inhaltsübersicht”. With [Cl3P?N? PCl3] and aluminium chloride [Cl3P?N? PCl3][AlCl4] is formed.  相似文献   

17.
Zusammenfassung Mo3CoB3, Mo3NiB3, W3CoB3 und W3NiB3 kristallisieren in einem eigenen Typ (W3CoB3-Struktur). Das trigonal prismatische Bauelement [T 6B]* ist zu Ketten vereinigt, wobei B3-Gruppen entstehen. Die Phasen sind vermutlich Bor-reicher als obiger Formel entspricht.
The crystal structure of W3CoB3 and the isotypic phases Mo3CoB3, Mo3NiB3, and W3NiB3
Mo3CoB3, Mo3NiB3, W3CoB3, and W3NiB3 were found to possess a new type of crystal structure (W3CoB3-structure type). Trigonal prismatic groups [T 6B]* are linked together forming chains in such a way that B3-groups occur. These borides do probably exist with a larger amount of boron as to compared with the formula.


Mit 2 Abbildungen  相似文献   

18.
Synthesis and Properties of Partially Silylated Tri- and Tetraphosphanes. Reaction of Lithiated Diphosphanes with Chlorophosphanes The reactions of Li(Me3Si)P? P(SiMe3)(CMe3) 1 , Li(Me3Si)P? P(CMe3)2 2 , and Li(Me3C)P? P(SiMe3)(CMe3) 3 with the chlorophosphanes P(SiMe3)(CMe3)Cl, P(CMe3)2Cl, or P(CMe3)Cl2 generate the triphosphanes [(Me3C)(Me3Si)P]2P(SiMe3) 4 , (Me3C)(Me3Si)P? P(SiMe3)? P(CMe3)2 6 , [(Me3C)2P]2P(SiMe3) 7 , and (Me3C)(Me3Si)P? P(SiMe3)? P(CMe3)Cl 8 . The triphosphane (Me3C)2P? P(SiMe3)? P(SiMe3)2 5 is not obtainable as easily. The access to 5 starts by reacting PCl3 with P(SiMe3)(CMe3)2, forming (Me3C)2 P? PCl2, which then with LiP(SiMe3)2 gives (Me3C)2 P? P(Cl)? P(SiMe3)2 11 . Treating 11 with LiCMe3 generates (Me3C)2P? P(H)? P(SiMe3)2 16 , which can be lithiated by LiBu to give (Me3C)2P? P(Li)? P(SiMe3)2 13 and after reacting with Me3SiCl, finally yields 5 . 8 is stable at ?70°C and undergoes cyclization to P3(SiMe3)(CMe3)2 in the course of warming to ambient temperature, while Me3SiCl is split off. 7 , reacting with MeOH, forms [(Me3C)2P]2PH. (Me3C)2P? P(Li)? P(SiMe3)2 18 , which can be obtained by the reaction of 5 with LiBu, decomposes forming (Me3C)2P? P(Li)(SiMe3), P(SiMe3)3, and LiP(SiMe3)2, in contrast to either (Me3C)2P? P(Li)? P(SiMe3)(CMe3) 19 or [(Me3C)2P]2PLi, which are stable in ether solutions. The Li phosphides 1 , 2 , and 3 with BrH2C? CH2Br form the n-tetraphosphanes (Me3C)(Me3Si)P? [P(SiMe3)]2? P(SiMe3)(CMe3) 23 , (Me3C)2P? [P(SiMe3)]2? P(CMe3)2 24 , and (Me3C)(Me3Si)P? [P(CMe3)]2? P(SiMe3)(CMe3) 25 , respectively. Li(Me3Si)P? P(SiMe3)2, likewise, generates (Me3Si)2P? [P(SiMe3)]2? P(SiMe3)2 26 . Just as the n-triphosphanes 4 , 5 , 6 , and 7 , the n-tetraphosphanes 23 , 24 , and 25 can be isolated as crystalline compounds. 23 , treated with LiBu, does nor form any stable n-tetraphosphides, whereas 24 yields (Me3C)2P? P(Li)? P(SiMe3)? P(CMe3)2, that is stable in ethers. With MeOH, 24 , forms crystals of (Me3C)2P? P(H)? P(SiMe3)? P(CMe3)2.  相似文献   

19.
A reinvestigation of the reaction of Ir(CO)Cl(PPh3)2, 1 with HSnPh3 has revealed that the oxidative-addition product Ir(CO)Cl(PPh3)2(H)(SnPh3), 2 has the H and SnPh3 ligands in cis-related coordination sites. Compound 2 reacts with a second equivalent of HSnPh3 by a Cl for H ligand exchange to yield the new compound H2Ir(CO)(SnPh3)(PPh3)2, 3. Compound 3 contains two cis- related hydride ligands. Under an atmosphere of CO, 1 reacts with HSnPh3 to replace the Cl ligand with SnPh3 and one of the PPh3 ligands with a CO ligand and also adds a second equivalent of CO to yield the 5-coordinate complex Ir(CO)3(SnPh3)(PPh3), 4. Compound 4 reacts with HSnPh3 by loss of CO and oxidative addition of the Sn-H bond to yield the 6-coordinate complex HIr(CO)2(SnPh3)2(PPh3), 5 that contains two trans-positioned SnPh3 ligands.  相似文献   

20.
Substituted μ3-carbido-capped tricobalt carbonyl clusters have been synthesised by reaction of [Co33-C(O)OCH2CHCH2)(CO)9] with a range of monodentate and chelating phosphane ligands. The products have been characterised by microanalysis, IR and NMR spectroscopy, mass spectrometry and, in the case of [Co33-CR)(CO)7(dppe)], [Co33-CR)(CO)7(dppm)], [Co33-CR)(CO)7(PPh3)2], [Co33-CR)(CO)7(PMe3)2] and [Co33-CR)(CO)6(PEt3)3] (R=C(O)OCH2CHCH2), single crystal X-ray diffraction.  相似文献   

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