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1.
The reaction of Pt(PPh3)n (n = 3 or 4) with [(CF3)3Ge]2Hg or (CF3)3GeHgPt(PPh3)2Ge(CF3)3 (I) gives a stable diplatinum complex [(CF3)3GePt(PPh3)2]2Hg (II). X-Ray analysis has established that compound II contains a Ge---Pt---Hg---Pt---Ge chain of C2 symmetry. Both of the Pt atoms have distorted square-planar coordinations. The bond lengths are: Pt---Hg, 2.630(2) and 2.665(2) Å; Ge---Pt, 2.410(4) and 2.407(4) Å.

Compound II reacts with dihydrogen in THF solution under mild conditions to give mercury and the hydride (CF3)3GePt(PPh3)2H. On interaction of II with R2Hg organomercurials (R = Cl, Et, GeEt3, Ge(CF3)3, Ge(C6F5)3) an unknown reaction takes place: Pt(PPh3)2 moieties migrate from the polymetallic grouping into the substrate with the formation of the corresponding RHgPt(PPh3)2R complexes or their demercuration products, R2Pt(PPh3);, (R = Cl, Et). The latter react further with complex I formed in the first step of the process to give Hg and (CF3)3GePt(PPh3)2R. The reaction schemes are discussed.  相似文献   


2.
The structure of the isomers present in the different physical states of n-C4F10, n-C6F14 and n-C8F18 is discussed, using previously published experimental data from IR and Raman spectroscopy and an approximate force field. It is proposed that the gauche form of n-C4F10, observed only in the gas and the liquid, is characterized by an internal rotational angle of about 120°. At least three non-trans forms exist in the gaseous and the liquid states of the C6 compound, but they disappear in the crystal. In contrast, the two solid phases of n-C8F19 which are stable at high temperatures are disordered and contain one or two gauche isomers; only the lowest temperature one possesses the all-trans form alone.  相似文献   

3.
发展了一种可见光诱导的N-苄基丙烯酰胺去芳香化成环合成多氟烷基化氮杂螺环已二烯酮的反应。 此反应以多氟烷基碘或溴为自由基源,以fac-Ir(ppy)3(fac:面式;ppy:2-苯基吡啶)作为光催化剂,在发光二极管(LED)蓝光灯照射条件下,使N-丙烯酰基-N-苄基苯甲酰胺串联自由基加成/去芳香化环合,合成了一系列含氟氮杂螺环已二烯酮类化合物,产率为61%~85%。 值得提出的是,此反应能快速在氮杂螺环已二烯酮骨架上引入多种多氟烷基基团如CF3I、C3F7I、C4F9I、C6F13、C8F17I、CH2CF2I和BrCF2CO2Et(Et:乙基)等,且底物适用范围广、反应条件温和(室温)、催化体系绿色,为具有潜在药用价值和生理活性的多氟烷基化氮杂螺环已二烯酮的合成提供了一条高效、快捷的新途径。  相似文献   

4.
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   

5.
The reactions of MnRe(CO)10 with As2(CF3)4 and MnCo(CO)9 with P2(CF3)4, As2(CF3)4, S2(CF3)2, Se2(CF3)2, (CF3)2EI (E = P, As), (CF3)2AsH, (CF3)2AsE′CF3 (E′ = S, Se), (CF3)2PSeCF3, Me2AsI and (CF3)2PPMe2, respectively, have been studied under various conditions. Besides already known mono- and binuclear compounds the heteronuclear complexes MnRe(CO)8[As(CF3)2]2 and MnCo(CO)7[E(CF3)2]2 (E = P, As) are formed. The reactions proceed via cleavage of the M---M′ bond and formation of the mononuclear species Mn(CO)5X and M′(CO)nY (M′ = Re, n = 5; M′ = Co, n = 4).  相似文献   

6.
In repeating and extending the syntheses of organo-arsenic polytungstates,we found that the "Degradation Method",taking sodium metatungstate as the starting material,was much more profita-ble.The known compound (CN3H6)5[(C6H5As)2W6O25H]2H2O(1) was read-ily reproduced with a high yield.A new compound (CN3H6)6[(p-OH,m-NO2C6H3As)2W6O25](2) was likewise synthesized.This "Degradation Method" using the reaction of sodium metatungstate with organo-anti-monate led to the isolation of four compounds with definite composition although amorphous in appearance.The preparations of organo-arsenic polymolybdates and organo-antimony polymolybdates were also studied and six new organo-arsenic polymolybdates were isolated: (CN3H6)5[(C6H5As)2MoO25H]H2O(3),(CN3H6)4[(n-C3H7As)2Mo5O21]2H O (4),(CNH)4[(n-C3H7As)2Mo6O24](5),Cs2[(CH3)2AsMo4O15H](6),相似文献   

7.
The attempted preparation of bis(trifluoromethylsulphanyl)thioketene is described. Mono-and di-(trifluoromethylsulphanyl)-substituted orthothioesters may be prepared fromCH3C(SC2H5)3 and CF3SCl in the presence of anhydrous ZnCl2. The unstable compoundshave been isolated and characterized. The corresponding CF3Se and CF3SO2 derivativesare only formed as intermediates which decompose to ketene diethylmercaptal. Suchmono- and di-substituted products are obtained in good yield from H2C=C(SC2H5)2 andCF3ECl (E=S, Se). The reaction of H2C=C(SC2H5)2 with CF3SO2F gave only poor yieldsof (CF3SO2)nCH2−n=C(SC2H5)2 (n=1, 2) which were only capable of characterizationin etheral solution by spectral means. Attempts to prepare (CF3S)2C=C=S by refluxing(CF3S)2CHC(O)Cl, (CF3S)2CHC(O)OH or (CF3S)2C=C=O with P4S10 in toluene yieldedonly the cyclic dimer and the corresponding 1,3,4-trithiolan.  相似文献   

8.
The reaction of 3,3-bis(trifluoromethyl)-1,1,2,4,4,4-hexafluoro-1-butylene and nonafluoro-n-butoxy-1,1,2-trifluoroethylene with tris(trimethylsilyl)phosphite gave fluorotrimethylsilane and the respective (Z)-alkenylbis(trimethylsilyl)phosphonates. In one case hydrolysis afforded the free phosphonic acid (CF3)3CCF = CFP(O) (OH)2. Using tri-n-butylphosphine and boron trifluoride etherate, 3,3-bis(trifluoromethyl)-1,1,2,4,4,4-hexafluoro-1-butylene and nonafluoro-n-butoxy-1,1,2-trifluoroethylene were converted into the corresponding phosphonium tetrafluoroborates, which when reacted further with iodine in the presence of Na2CO3 gave the iodo derivatives (CF3)3CCF = CFI and C4F9OCF = CFI.  相似文献   

9.
Reaction of [Ru3(CO)12 with (CF3)2P---P(CF3)2 in p-xylene at 140°C yielded the compounds [Ru4(CO)13{μ-P(CF3)2}2] (1), [Ru4(CO)14{μ-P(CF3)2}2] (2) and [Ru4(CO)11{μ-P(CF3)2}4] (3). Reaction with [(μ-H)4Ru4(CO)12] under similar conditions yielded [(μ-H)3Ru4(CO)12{μ-P(CF3)2}] (4). All four compounds have been characterised by X-ray crystallography. The fluxional behaviour of the hydrides in 4 has also been studied by variable-temperature NMR spectroscopy. Compounds 1, 2 and 4 were also obtained from the reactions of Ru3(CO)12 with (CF3)2PH in dichloromethane at 80°C.  相似文献   

10.
The stereochemical nonrigidity of RfCo(PF3)x(CO)4-x(Rf=CF3,C2F5,C3F7,x=0-4) was studied at the theoretical level of B3LYP/6-31 1+G^* via Gaussian 09.The intramolecular rearrangements in these penta-coordinated compounds are mainly caused by the vibrations of perfluoroalkyl groups.All the barriers along the reaction coordinate are less than 66.9 kJ/mol,which indicates that the rearrangements are kinetically favorable and hard to elucidate by experiment.Besides,ligand PF3 is a ligand similar to CO,the energy difference between the reactant and product is small.  相似文献   

11.
Anionic surfactants having two polyfluoroalkyl chains per molecule, i.e. the sodium salt of bis(1H, 1H, 2H,2H-heptadeca-fluorodecyl)-2-sulfosuccinate, CF3(CF2)7(CH2)2OCOCH2CH(SO3Na)COO(CH2)2(CF2)7CF3, the sodium salt of bis(1H, 1H, 2H, 2H-tridecafluoro-octyl)-2-sulfosuccinate, CF3(CF2)5(CH2)2OCOCH2CH(SO3Na)COO(CH2)2(CF2)5CF3, and the sodium salt of bis(1H, 1H, 2H, 2H-nonafluorohexyl)-2-sulfosuccinate, CF3(CF2)3(CH2)2OCOCH2CH(SO3Na)COO(CH2)2(CF2)3CF3, have been prepared from maleic anhydride, the corresponding alcohols possessing a polyfluoroalkyl chain and sodium hydrogen sulfite. The flocculation and redispersion abilities of these surfactants for dispersed magnetic particles in water have been examined to investigate the effect of the chain length. It was found that this ability was enhanced by an increase in the chain length. The contact angles for water for pelleted surface-modified magnetite have been measured. In order to compare this ability and the contact angles, data for other fluorinated surfactant have been obtained. The Kraff point, the surface tension and the pNa of the aqueous surfactant solutions have also been measured.  相似文献   

12.
Characteristics of methyl methacrylate (MMA) polymerization using oscillating zirconocene catalysts, (2-Ph-Ind)2ZrX2 (X = Cl, 1; X = Me, 2), mixtures of rac- and meso-zirconocene diastereomers, (SBI)ZrMe2 [3, SBI = Me2Si(Ind)2] and (EBI)ZrMe2 [4, EBI = C2H4(Ind)2], as well as diastereospecific metallocene pairs, rac-4/Cp2ZrMe2 (5) and rac-4/CGCTiMe2 [6, CGC = Me2Si(Me4C5)(t-BuN)], are reported. MMA polymerization using the chloride catalyst precursor 1 activated with a large excess of the modified methyl aluminoxane is sluggish, uncontrolled, and produces atactic PMMA. On the other hand, the polymerization by a 2/1 ratio of 2/B(C6F5)3 or 2/Ph3CB(C6F5)4 is controlled and produces syndiotactic PMMA. Mixtures of diastereomeric ansa-zirconocenes 3 or 4 containing various rac/meso ratios, when activated with B(C6F5)3, yield bimodal PMMA; this behavior is attributed to the meso-diastereomer that, in its pure form, affords bimodal, syndio-rich atactic PMMA. For MMA polymerization using diastereospecific metallocene pairs, rac-4/5 and rac-4/6, the isospecific catalyst site dominates the polymerization events under the conditions employed in this study, and the aspecific and syndiospecific sites are largely nonproductive, thereby forming only highly isotactic PMMA.  相似文献   

13.
Photolyses of CF3C(O)X and C2F5C(O)X (X=Cl, F) at 254 nm in the presence of O2 yield the perfluorinated radicals C2F5O (C2) and CF3O (C1), respectively. The C2 radicals decompose to give CF3 radicals:
C2F5O→CF3+CF2O
which, in turn, react with O2 leading to the formation of C1 radicals. When in addition to O2, CO is present, the C1 radicals react with it leading to its catalytic oxidation to CO2. The trioxide CF3OC(O)O3C(O)OCF3 was observed following the photolysis of all four halides in the presence of O2 and CO.

The other radical partners coming from the initial step in the photolysis (XC(O)) as well as the products of their reaction with O2 (XC(O)Oy, y=1, 2) do not react with CO but when X=F they lead to the formation of a new stable peroxy molecule with the formula CF3OC(O)O2C(O)F. Some of the properties of this new molecule, its stability and its IR features are presented in this work.  相似文献   


14.
The compounds Cp2VR (R = CH3, C2H5, n-C3H7, n-C4H9, n-C5H11, CH2C(CH3)3 or CH2Si(CH3)3) have been prepared from Cp2 VCl and RMgX in n-pentane. The air-sensitive compounds are stable at room temperature, but decompose between 65 and 138°C. The thermal stability decreases in the order R = CH3 CH2Si(CH3)3 > C2H5 > CH2C(CH3)3 > n-C5H11 > n-C4H9 > n-C3H7. Compounds with R = i-C3H7 or t-C4H9 could not be obtained.  相似文献   

15.
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   

16.
Complexes trans-[PtX(L)(PPh3)2]A [1: X = CF3; A = BF4; L = NCNH2, NCNMe2, NCNEt2, or NCNC(NH2)2. 2: X = Cl; A = BPh4; L = NCNMe2 or NCNEt2] and cis-[PtCl(L)(PPh3)2][BPh4] [3: L = NCNH2 or NCNC(NH2)2], which appear to be the first cyanamide or cyanoguanidine complexes of platinum to be reported, have been prepared by treatment of trans-[PtBr(CF3)(PPh3)2] (in CH2Cl2/acetone and in the presence of Ag[BF4]) or of cis-[PtCl2(PPh3)2] (in THF and in the presence of Na[BPh4]), respectively, with the appropriate substrate. In KBr pellets or in solution 1 (L = NCNMe2 or NCNEt2) undergoes ready replacement of the organocyanamide (under the trans influence of CF3) by bromide to regenerate trans-(PtBr(CF3)(PPh3)2]. The X-ray structure of 1 (X = CF3, A = BF4, L = NCNEt2) is also reported, and shows the presence of two apical intramolecular contacts of the metal with two ortho-hydrogen atoms of the phosphines, whereas the amine N atom of the diethylcyanamide is trigonal planar in the linear NCN framework with a delocalized π system.  相似文献   

17.
Ethylene polymerization was conducted with bis(cyclopentadienyl)zirconium dichloride (1) and rac-dimethylsilylenebis(indenyl)zirconium dichloride (2) combined with trialkylaluminum (AlR3; R=methyl (Me), ethyl (Et), isobutyl (iBu))/triphenylcarbenium tetrakis(pentafluorophenyl)borate (Ph3CB(C6F5)4) or tris(pentafluorophenyl)borane (B(C6F5)3) to study the effect of cocatalysts on polymerization rate (Rp). When AlMe3 was used, no activity or very low activity was observed with both zirconocenes regardless of the borane compounds used. The replacement of AlMe3 to AlEt3 or AliBu3 with 1–AlR3/Ph3CB(C6F5)4 caused polymerization and induction time was observed to reach the maximum Rp. Especially in the case of using AlEt3, it took about 30 min to show the activity. When B(C6F5)3 was used, AlEt3 was not effective but AliBu3 gave the highest activity among all the combinations of AlR3 and the borane compounds. In the case of polymerization with 2 using Ph3CB(C6F5)4, high activity was observed with both AlEt3 and AliBu3 without any induction period. When B(C6F5)3 was used instead of Ph3CB(C6F5)4, very low activity was observed with AlEt3. On the other hand, high activity was observed with AliBu3, and the maximum Rp was found at the beginning of the polymerization. The effect of AlR3 on the formation of active species was discussed based on these results.  相似文献   

18.
The coordinating properties of the trifluoromethyl elemental compounds Me2PP(CF3)2 and Me2AsP(CF3)2 have been studied by the synthesis and spectroscopic investigations (IR, NMR, MS) of their complexes cis-M(CO)4L2 (A), [(CO)4ML]2 (B) and [(CO)5M]2L (C) (M = Cr, Mo, W). Complexes of type A with L = Me2PP(CF3)2 are obtained in good yield by reaction with M(CO)4NBD (NBD = norbornadiene), whereas with L = Me2AsP(CF3)2 the homobinuclear compounds B are formed. The attempt to prepare the cis-M(CO)4[Me2AsP(CF3)2]2 complexes by treating M(CO)4(Me2AsH)2 with P2(CF3)4 is successful only for M = W. Binuclear compounds of type B or C, in general, can be prepared by stepwise reaction of the ligands with either M(CO)4NBD or M(CO)5THF.  相似文献   

19.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C5Me4CH2PMe2)], where M=Li+ (1), Na+ (2), or K+ (3), and [Li(C5H4CR′2PMe2)], where R′2=Me2 (4), or (CH2)5 (5), [HC5Me4CH2PMe2H]X, where X=Cl (6) or PF6 (7) and [HC5Me4CH2PMe2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C5R4CR′2PMe2)2], where R=Me, R′=H (9); R=H and R′2=Me2 (10), or (CH2)5 (11), [Fe(η-C5H4CMe2PMe3)2]I2 (12), [Fe{η-C5Me4CH2P(O)Me2}2] (13), [Zr(η-C5R4CR′2PMe2)2Cl2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C5H4CMe2PMe2)2]Cl2] (16), [Zr(η-C5H4CMe2PMe2)2Me2] (17), {[Zr(η-C5Me4CH2PMe2)2]Cl}{(C6F5)3BClB(C6F5)3} (18), [Zr{(η-C5Me4CH2PMe2)2Cl2}PtI2] (19), [Mn(η-C5Me4CH2PMe2)2] (20), [Mn{(η-C5Me4CH2PMe2B(C6F5)3}2] (21), [Pb(η-C5H4CMe2PMe2)2] (23), [Sn(η-C5H4CMe2PMe2)2] (24), [Pb{η-C5H4CMe2PMe2B(C6F5)3}2] (25), [Pb(η-C5H4CMe2PMe2)2PtI2] (26), [Rh(η-C5Me4CH2PMe2)(C2H4)] 29, [M(η,κP-C5Me4CH2PMe2)I2], where M=Rh (30), or Ir, (31).  相似文献   

20.
Due to variation in ligand's conformation, metal node's connecting geometry, and secondary building process by anions, bat-like, dumbell-like, diamondoid, or pillar-layer topologies are achieved.  相似文献   

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