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1.
Treatment of octafluorotoluene (2) with approximately one-molar equivalents of the oximates R1R2C = NO~ M+ (R1 = R2=Me;R1 = R2 = Ph; R1 = Me, R2 = Ph;M = Na) (6a-c) in diethyl ether gives 4-(R1R2C = NO)C6F4CF3 (7a-c) as the only isolated products. Corresponding reaction of 3,5-dichlorotrifluoropyridine (3) with the oximates 6a-c affords 4-and 2-(R1R2C = NO)C5F2C12N (8a-c) and (9a-c), respectively (4-/2ratios at −35 °C: 65:35; 30:70; 12:88) ; the lithium oximates (R1 = R2 =Ph ; R1 = Me, R2 = Ph; M = Li) (6d) and (6e) give comparable results. With 3-chlorotetrafluoropyridine (4), treatment with sodium oximate 6c gives 4-(PhCMe = NO)-3-ClC5F3N (10) and 2-(PhCMe = NO)-5ClC5F3N (11) (ratio 44:56 at −35 °C). Such competition between SNAr attack of these alkali-metal oximates at the C-4 and C-2 positions of chlorofluoropyridines 3 and 4 can be rationalized by invoking chelation of an alkali-metal cation with ring nitrogen in the transition state leading to formation of an orthio-quinonoidal σ-complex. Exclusive initial attack at the C-4 ring site appears to occur in the reaction of tetrafluoropyrimidine (5) with oximates 6a and 6c to afford 4-(MeC = NO)C4F3N2 (12a) and 4-(PhCMe=NO)C4F3NN2 (12b), respectively; Some further attack on product 12b by oximate 6c at the C-6 site takes place to give the disubstituted derivative 4,6-(PhCMe=NO)2C4F2N2 (13).  相似文献   

2.
报导了用X射线衍射法测定的钆、铽、铒、铥的四种乙酰丙酮三水络合物的晶体结构。确定了它们的晶体学参数与原子在晶胞中的分数坐标。讨论了晶体结构与分子结构的特征。  相似文献   

3.
1-Methylpiperazine was employed to crystallize with 2,4-dihydroxybenzoic acid and 1,8-naphthalene acid, affording two multi-component hydrogen-bonding salts [(C5H14N2)2+·(C7H5O4)2-·H2O](1) and [(C5H14N2)2+(C12H6O4)2ˉ·2H2O](2). These two forms of salts are both monoclinic systems with space group P21/c(14). The lattice parameters of salts 1 and 2 are a=1.32666(10) nm, b=0.90527(7) nm, c=1.67107(13) nm, β=103.125(1)° and a=1.4950(2) nm, b=0.75242(15) nm, c=1.6563(3) nm, β=92.834(2)°, respectively. Expected classical hydrogen bonds N―H…O and O―H…O appear in the chargetransfer salts, and asymmetric units of these two forms both contain water molecules which play a significant role in building novel supramolecular architectures. Robust hydrogen-bond interactions between 1-methylpiperazine and aromatic acid provide sufficient driving force to direct the two crystals to three-dimensional structures. Weak interactions C―H…O emerging in salts 1 and 2 further enhance their crystal structures. As a consequence, hydrogen-bonding interactions in these compounds afford diverse 3D net supramolecular architectures. Thermal stability of these compounds was investigated by thermogravimetric analysis(TGA).  相似文献   

4.
四甲基双硅桥联环戊二烯基钠与无水三氯化稀土在THF溶剂中反应合成了标题配合物Me4Si2(C5H4)2LnCl[Ln:3Nd,4Sm,5Gd,6Y]和配合物Me4Si2(C5H4):Ln(C5H5)(THF)n[Ln:1La,n=1;2Pr,n=0].通过元素分析、1HNMR、13CNMR和MS确证了配合物的结构,在THF溶液中重结晶获得配合物4的单晶,x射线衍射证明晶体结构为二聚体,4为单斜晶系,空间群为P21/c,晶体学数据a=1.2982(3)nm,b=1.2269(3)nm,c=1.3681(2)nm,β=96.79(2)°,V=2.162(1)nm3,Z=2,Dx=1.53g/cm3,偏差因子R=0.068.  相似文献   

5.
提钪工艺中常使草酸钪溶于过量草酸铵溶液中。但文献中有关钪与草酸离子配位作用的报导甚少。等用分光光度法测定了ScC2O4+配离子的稳定常数,而J·Stary则用分配法测定了SC(C2O4)33-配离子的稳定常数,这些工作都没有对溶液中可能生成各级配离子进行研究。  相似文献   

6.
Cephalosporin derivatives have been a subject in the field of β-lactam antibiotics due to their broad-spectrum biological activities in recent years. Chemical manipulation of the C-3 and 7β-position in the cephalosporin molecule has resulted in the discovery of numerous novel antibiotics. In general, the C-3 position of the cephalosporin were substituted with heterocyclyl sulfurs or nitrogens and the 7β-position were substituted with heterocycles or aryl1. The side chain at 7β-position determined their antibacterial activities and antibacterial spectrum, moreover, the substituted groups at C-3 position not only affect pharmacokinetic properties, but antibacterial activities and antibacterial spectrum as well.2 Roche Reiner company found that the activities of cephalosporin can be improved by changing the R of RCONH- at 7β-position of 7ACA and introducing various thioazoleheterocycles into C-3 position of it.3 It is no doubt that these heterocycles increased their activities and wided their antibacterial spectrum. In the course of our studies on the modification of cephalosporin, our efforts have been focused on introducing heterocycles into C-3 and 7β-position of 7ACA with the hope of achieving better antibiotics.  相似文献   

7.
苯并-15-冠-5苦味酸钠配合物单晶由丙酮-乙醇(1:1)溶液中得到,晶体属单斜空间群C2h5-P21/n,晶体学数据:a=11.134(3)Å,6=13.541(3)Å,c=14.927(4)Å,β=93.41(2)°Å,V=2246.4Å3,Z=4,晶体结构由直接法解出,晶体结构分析结果表明,与苯环共轭的芳醚氧原子上的电子密度可通过苯环而转移。  相似文献   

8.
Synthesis and Characterization of Zinc Succinate, Zn(C4H4O4)   总被引:3,自引:0,他引:3  
Introduction  Succinateion (C4H4O4) 2 -(—OOCCH2 CH2 COO— )isaversatileligandsinceeachofthefourterminalcarboxyloxygensisabletoparticipateincoordinationtocentralmetalatom(s)inadditiontotheflexibilityoftheC—Cbone .Suchcoordinatingversatilityhasbeenreflectedinseve…  相似文献   

9.
Likewise the 1,3,4-thiadiazole nucleus which incorporates an N-C-S linkage exhibits a large number of biological activities[1]. The fused 1,3,4-triazolo[3,4-b]-1,3,4-thiadiazoles derivatives show various biological effects, such as antifungal[2], antibacterial, hypotensive and CNS depressant activities[3]. The novel 3-[5-methyl-1-(4-methylphenyl)-1,2,3-triazol-4-yl]-s-triazolo[3,4-b]-1,3,4-thiadiazole 6 have been synthesized by the condensation of 4-amino-5-mercapto-3-[5-methyl-1-(4-methylphenyl)-1,2,3-triazol-4-yl]-s-triazole 5 with formic acid in the presence of phosphorus oxychloride. The compound 5 was prepared from 4 that was prepared from 1 throng 2 and 3. Recently, we obtained the crystal structure of the novel compound 3-[5-methyl-1-(4-methylphenyl)-1,2,3-triazol-4-yl]-s-triazolo[3,4-b]-1,3,4-thiadiazole, C14H12Cl3N7S, Mr=416.72, Crystallizes in the triclinic space group with unit cell parameters a=9.049(2), b=10.486(3), c=10.843(2)Å, α=116.79(2), β=93.83(2), γ-100.64(3)°. V=889.3(4)Å3, Z=1, Dx-0.778 Mgm-3. The final R was 0.0535.  相似文献   

10.
Chiralityduetoalkylbranchingisabundantamongseveralnaturallyoccurringsecondarymetabolites .Thisstructurefeatureisparticularlypredominantamonginsectpheromones[1] ,manyofwhichareofeconomicsignificance .Asaresult,aconsiderableefforthasbeenmadetosynthesizethem…  相似文献   

11.
In order to understand the nature of the putative cationic 12-electron species [M(η51-C5R4SiMe2NR′)R″]+ of titanium catalysts supported by a linked amido-cyclopentadienyl ligand, several derivatives with different cyclopentadienyl C5R4 and amido substituents R′ were studied systematically. The use of tridentate variants (C5R4SiMe2NCH2CH2X)2− (C5R4=C5Me4, C5H4, C5H3tBu; X=OMe, SMe, NMe2) allowed the NMR spectroscopic observation of the titanium benzyl cations [Ti(η51-C5Me4SiMe2NCH2CH2X)(CH2Ph)]+. Isoelectronic neutral rare earth metal complexes [Ln(η51-C5R4SiMe2NR′)R″] can be expected to be active for polymerization. To arrive at neutral 12-electron hydride and alkyl species of the rare earth metals, we employed a lanthanide tris(alkyl) complex [Ln(CH2SiMe3)3(THF)2] (Ln=Y, Lu, Yb, Er, Tb), which allows the facile synthesis of the linked amido-cyclopentadienyl complex [Ln(η51-C5Me4SiMe2NCMe3)(CH2SiMe3)(THF)]. Hydrogenolysis of the linked amido-cyclopentadienyl alkyl complex leads to the dimeric hydrido complex [Ln(η51-C5Me4SiMe2NCMe3)(THF)(μ-H)]2. These complexes are single-site, single-component catalysts for the polymerization of ethylene and a variety of polar monomers such as acrylates and acrylonitrile. Nonpolar monomers such as -olefins and styrene, in contrast, give isolable mono-insertion products which allow detailed studies of the initiation process.  相似文献   

12.
The reaction of the anionic mononuclear rhodium complex [Rh(C6F5)3Cl(Hpz)]t- (Hpz = pyrazole, C3H4N2) with methoxo or acetylacetonate complexes of Rh or Ir led to the heterodinuclear anionic compounds [(C6F5)3Rh(μ-Cl)(μ-pz)M(L2)] [M = Rh, L2 = cyclo-octa-1,5-diene, COD (1), tetrafluorobenzobarrelene, TFB (2) or (CO)2 (4); M = Ir, L2 = COD (3)]. The complex [Rh(C6F5)3(Hbim)] (5) has been prepared by treating [Rh(C6F5)3(acac)] with H2bim (acac = acetylacetonate; H2bim = 2,2′-biimidazole). Complex 5 also reacts with Rh or Ir methoxo, or with Pd acetylacetonate, complexes affording the heterodinuclear complexes [(C6F5)3Rh(μ-bim)M(L2)] [M = Rh, L2 = COD (6) or TFB (7); M = Ir, L2 = COD (8); M = Pd, L2 = η3-C3H5 (9)]. With [Rh(acac)(CO)2], complex 5 yields the tetranuclear complex [{(C6F5)3Rh(μ-bim)Rh(CO)2}2]2−. Homodinuclear RhIII derivatives [{Rh(C6F5)3}2(μ-L)2]·- [L2 = OH, pz (11); OH, StBu (12); OH, SPh (13); bim (14)] have been obtained by substitution of one or both hydroxo groups of the dianion [{Rh(C6F5)3(μ-OH)}2]2− by the corresponding ligands. The reaction of [Rh(C6F5)3(Et2O)x] with [PdX2(COD)] produces neutral heterodinuclear compounds [(C6F5)3Rh(μ-X)2Pd(COD)] [X = Cl (15); Br (16)]. The anionic complexes 1–14 have been isolated as the benzyltriphenylphosphonium (PBzPh3+) salts.  相似文献   

13.
The hydroxo-complexes [{PdR(PPh3)(μ-OH)}2] (R = C6F5 or C6Cl5) have been obtained by reaction of the corresponding [{PdR(PPh3)(μ-Cl)}2] complexes with NBu4OH in acetone. In this solvent, the reaction of the hydroxo-bridged complexes with pyrazole (Hpz) and 3,5-dimethylpyrazole (Hdmpz) in 1:2 molar ratio leads to the formation of the new complexes [{Pd(C5F5)(PPh3)(μ-azolate)}2] and [{Pd(C6Cl5)(PPh3)}2(μ-OH)(μ-azolate)] (azolate = pz or dmpz). The reaction of the bis(μ-hydroxo) complexes with Hpz and Hdmpz in acetone in 1:1 molar ratio has also been studied, and the resulting product depends on the organic radical (C6F5 or C6Cl5) as well as the azolate (pz or dmpz). The identity of the isomer obtained has been established in every case by NMR (1H, 19F and 31P) spectroscopy. The reaction of the bis(μ-hydroxo) complexes with oxalic (H2Ox) and acetic (HOAc) acids yields the binucle ar complexes [{PdR(PPh3)}2(μ-Ox)] (R = C6F5 or C6Cl5) and [{Pd(C6F5)(PPh3)(μ-OAc)}2], respectively. [{Pd(C6F5)(PPh3)(μ-OH)}2] reacts with PPh3 in acetone in 1:2 ratio giving the mononuclear complex trans-[Pd(C6F5) (OH)(PPh3)2], whereas the pentachlorophenylhydroxo complex does not react with PPh3, even under forcing conditions.  相似文献   

14.
《高等学校化学学报》1999,20(8):1172-1178
利用Co2(CO)8与[Cl3CC(O)OCH2]2的反应合成了以C(O)OCH2CH2OC(O)桥联两个Co3C四面体骨架为特征的新型双四面体簇合物[(CO)9Co33-C)C(O)OCH2]2(1);1与不同物质的量比的Na[M(CO)3C5H4R](M=Mo,W;R=H,C(O)Me)反应,得到一步交换的产物(CO)9Co33-C)C(O)OCH2CH2OC(O)(μ3-C)Co2M(CO)8(C5H4R)[M=Mo,R=H(2);M=Mo,R=C(O)Me(3);M=W,R=H(4);M=W,R=C(O)Me(5)]或两步交换的产物[(C5H4R)(CO)8Co2M(μ3-C)C(O)OCH2]2[M=Mo,R=H(6);M=Mo,R=C(O)Me(7);M=W,R=H(8);M=W,R=C(O)Me(9)].5或9分别与Na[Mo(CO)3C5H5]以12的物质的量比反应得到含一个手性四面体骨架(CoMoWC)的(C5H5)(CO)8Co2Mo(μ3-C)C(O)OCH2CH2O·C(O)(μ3-C)CoMoW(CO)7(C5H4C(O)Me)(C5H5)(10)或含两个手性四面体骨架(CoMoWC)的[(C5H5)(C5H4C(O)Me)(CO)7CoMoW(μ3-C)C(O)OCH2]2(11);对化合物1_11进行了CH元素分析、IR和1HNMR等表征.结果表明,在金属交换反应中处于不同簇环境下的Co(CO)3基团反应活性不同.对化合物1进行了晶体X射线衍射分析.化合物1的晶体属单斜晶系,P21/n(#14)空间群,晶胞参数a=0.933 0(2)nm,b=1.519 7(4)nm,c=1.178 3(4)nm,=91.16(2)°,Z=2,F(000)=972.分子结构呈中心对称.  相似文献   

15.
Liquid crystalline 4-XC6H4N=NC6H4X-4′ [X = C4H9 (1a), C1OH21 (1b), OC4H9 (1c), OC8H17(1d)] can be easily prepared in high yields from the corresponding anilines. In order to study the influence of metals on the thermal properties of these materials, we have obtained adducts [AuCl 3(4-C4H9OC6H4N=NC6H4OC4H9-4′)] (2) and [Ag(OC1O3)L2] [L = 4-XC6H4N=NC6H4X-4′; X = OC4H, (3a), OC8H17 (3b)]. The silver adducts show themotropic behaviour. Mercuriation of dialkylazobenzenes 1a-b takes place with [Hg(OAc)2] and LiCl to give [Hg(R)Cl] [R = C6H3(N=NC6H4X-4′)-2, X-5; X = C4H9 (bpap) (4a), C10H21 (dpap) (4b)] while dialkoxyazobenzenes 1c–d require [Hg (OOCCF3)2] to obtain [Hg(R)Cl] [R = C6H3(N---NC6H4X-4′)-2, X-5; X = OC4H9 (bxpap) (4c), OC 8H17 (4d)]. 4a-c react with NaI to give [HgR2] [R= bpap (5a), dpap (5b), bxpap (5c), oxpap (5d)l. Both chloroaryl-, 4a and 4c, and diaryl-mercurials, 5a and 5c, act readily as transmetailating agents towards [Me4N] [AuCl4] in the presence of [Me4N]Cl to give [Au(η2-R)Cl2] [R = bpap (6a), bxpap (6b)]. After reaction of [AuCl 3(tht)] (tht = tetrahydrothiophene) with [Me4N]Cl and 4b (1:2:1), [Me4N][Au(dpap)Cl3] (7) can be isolated. C---H activati bxpap (8b)]. None of the complexes 4–8 shows mesomorphic behaviour.  相似文献   

16.
In order to complete the rs structure of chlorobenzene given in a preceding paper, a variety of isotopic species of this molecule were synthesized and their microwave spectra studied. This made twenty isotopic species available, enabling the determination of the geometrical parameters by a least squares method. Fitting only differences of moments of inertia either for monosubstituted species or to multiply substituted species gave the same result. They hardly differ from the ro values and agree with the rs values obtained by the Kraitchman equations. The resulting error limits were reduced, however.

The following structural parameters were obtained, C1C2 = 1.399 Å, C2C3 = 1.386 Å, C3C4 = 1.3976 Å, C1Cl = 1.7248 Å, C2H2 = 1.080 Å, C3H3 = 1.081 Å, C4H4 = 1.081 Å, C6C1C2 = 120° 16, C1C2C3 = 119°78, C2C3C4 = 120°24, C3C4C5 = 119°80, C1C2H2 = 119°45, C2C3H3 = 119°76.

The structure of the ring differs significantly from C6 symmetry. The deformation can be regarded as a compression of the position C1 while the angle of C2H2 bond is also changed.  相似文献   


17.
新型桥联双四面体簇合物的合成与表征   总被引:2,自引:0,他引:2  
利用(μ3-CCO2Et)Co3(CO)9与单阴离子试剂[Mo(CO)35-C5H4R)]-[R=H,C(O)Me]的反应合成了2个新的含CCo2Mo骨架的簇合物(μ3-CCO2Et)Co2Mo(CO)85-C5H4R)[R=H(1);R=C(O)Me(2)],进而用其与双阴离子试剂{-M(CO)35-C5H4C(O)]}2-1,4-C6H4[M=Mo,W]反应合成了4个双四面体簇合物{(μ3-CCO2Et)CoMoM(CO)75-C5H4R)[η5-C5H4C(O)]}2-1,4-C6H4[M=Mo,R=H(3);M=Mo,R=C(O)Me(4);M=W,R=H(5);M=W,R=C(O)Me(6)].这6个化合物的C和H元素分析,IR,1HNMR等表征都与其结构一致.晶体X射线衍射分析表明,化合物2属单斜晶系,C2/c空间群,晶胞参数a=1.1264(3)nm,b=1.1879(3)nm,c=3.3565(10)nm,β=93.320(5)°,V=4.484(2)nm3,Z=8,Dc=1.867g·cm-3,F(000)=2480,R=0.0369,wR=0.1150.  相似文献   

18.
采用自制的新型双苯并环己酮芳亚胺镍催化剂双苯并环己酮-2,6-二甲基苯亚胺镍(Ⅱ)(Ni{C10H8(O)C[2,6-C6H3(CH3)2N]CH3}2, C1)和双苯并环己酮-2,6-二氯苯亚胺镍(Ⅱ)(Ni{C10H8(O)C[2,6-C6H3Cl2N]CH3}2, C2)与三五氟苯硼[B(C6F5)3]结合, 在一定的反应条件下可高效催化降冰片烯(NB)与甲基丙烯酸正丁酯(n-BMA)的乙烯基加成共聚合. 提出了催化聚合时存在的可能失活机理; 研究了不同单体投料比对催化活性、 产率及产物性能的影响. 根据Kelen-Tüdõs方法分别估算出2种单体在不同催化体系下的竞聚率, 即当催化体系为C1/B(C6F5)3时, 竞聚率rn-BMA=0.02, rNB=16.28, rNB·rn-BMA=0.32; 当催化体系为C2/B(C6F5)3时, rn-BMA=0.01, rNB=64.83, rNB·rn-BMA=0.65. 结果表明, 2种单体在2种体系催化下均为无规共聚合.  相似文献   

19.
The reactions of the half-sandwich molybdenum(III) complexes CpMo(η4-C4H4R2)(CH3)2, where Cp=η5-C5H5 and R=H or CH3, with equimolar amounts of B(C6F5)3 have been investigated in toluene. EPR monitoring shows the formation of an addition product which does not readily react with Lewis bases such as ethylene, pyridine, or PMe3. The analysis of the EPR properties and the X-ray structure of a decomposition product obtained from dichloromethane, [CpMo(η4-C4H6)(μ-Cl)(μ-CH2)(O)MoCp][CH3B(C6F5)3], indicate that the borane attack has occurred at the methyl position.  相似文献   

20.
LnCl3 (Ln=Nd, Gd) reacts with C5H9C5H4Na (or K2C8H8) in THF (C5H9C5H4 = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C5H9C5H4)LnCl2(THF)n (orC8H8)LnCl2(THF)n], which further reacts with K2C8H8 (or C5H9C5H4Na) in THF to form the litle complexes. If Ln=Nd the complex (C8H8)Nd(C5H9C5H4)(THF)2 (a) was obtained: when Ln=Gd the 1 : 1 complex [(C8H8)Gd(C%H9)(THF)][(C8H8)Gd(C5H9H4)(THF)2] (b) was obtained in crystalline form.

The crystal structure analysis shows that in (C8H8)Ln(C5H9C5H4)(THF)2 (Ln=Nd or Gd), the Cyclopentylcyclopentadieny (η5), cyclooctatetraenyl (η8) and two oxygen atoms from THF are coordinated to Nd3+ (or Gd3+) with coordination number 10.

The centroid of the cyclopentadienyl ring (Cp′) in C5H9C5H4 group, cyclooctatetraenyl centroid (COTL) and two oxygens (THF) form a twisted tetrahedron around Nd3+ (or Gd3+). In (C8H8)Gd(C5H9C5H4)(THF), the cyclopentyl-cyclopentadienyl (η5), cyclooctatetraenyl (η8) and one oxygen atom are coordinated to Gd3+ with the coordination number of 9 and Cp′, COT and oxygen atom form a triangular plane around Gd3+, which is almost in the plane (dev. -0.0144 Å).  相似文献   


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