首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 22 毫秒
1.
Dehydrohalogenation and metallation of boranato-bis-trimethylphosphonium salts (1), using two equivalents of a lithiumalkyl in tetrahydrofuran, leads to a solvated organolithium reagent H2B[(CH3)2PCH2]2Li (3) which can be converted into a 1:1n1-complex with tetramethylethylenediamin (4).3 reacts with anhydrous metal(II) halides to form spirocyclic coordination compounds of the type H2B[(CH3)2PCH2]2 M[CH2P(CH3)2]2BH2 (5–9,M=Be, Mg, Zn, Cd, Hg). The reaction of [(CH3)3PBH2P(CH3)3]Br (1) with lithium tetramethylmetalates Li[M(CH3)4],M=Al, Ga, on heating in the absence of a solvent affords the metallocycles H2B[(CH3)2PCH2]2 M(CH3)2 (10, 11) with evolution of methane. The products can be sublimed from the reaction mixture. The proposed structures of the new compounds, with tetrahedrally coordinated central atoms and strong covalent metal-carbon interactions, are supported by mass, IR and1H,7Li,11B,13C, and31P NMR spectra. Compound9 represents a rare case of a tetracoordinate organomercurial, compound5 is the first nonionic tetraalkylberyllate.
  相似文献   

2.
The1H and13C NMR spectral parameters of α-, β-, and y-lewisites1–5 were obtained and a new isomer,cis,trans,trans-γ-lewisite5, was isolated and identified on the basis of chemical shifts, relative intensities of the signals, and the intra-chain (3 J hh ,3 J ch ) and interchain (3 J casch ) coupling constants. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1833–1835, October, 1993.  相似文献   

3.
The reaction of Os3(μ-Cl)2(CO)10 (1) with Ph2PCH2PPh2 (dppm) in a toluene solution at 65°C results in novel osmium complexes [Os3(μ-Cl)2(CO)9]2(dppm) (2) and [Os3(μ-Cl)2(CO)8]2(dppm)2 (3). Compounds 2 and 3 were characterized by1H and31P NMR, and IR spectroscopy and their structures were established by X-ray analysis. In both compounds, dppm is a bridging ligand between the two cluster units. Molecule3 can be considered as an unusual 12-membered macrocycle containing C, P, Cl, and Os atoms in the ring. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1844–1851, September, 1998.  相似文献   

4.
The effects of a new axial impeller (HTPG4) on oxygen volumetric transfer coefficient, K L a, and xylanase production by Penicillium canescens 10-10c were studied and compared for dual-impeller systems, one with one DT4 impeller below and one HTPG4 above (DT4-HTPG4) and one with two DT4 (DT4-DT4) impellers, in a 5-L bioreactor. The volumetric coefficient of oxygen transfer was measured in culture medium using a gassing-out method at different gassing rates and agitation speeds. We observed that the DT4-HTPG4 combination provided better K L a performance than the DT4-DT4 combination. The two combinations were also tested for their influence on xylanase production by a filamentous microorganism; P. canescens 10-10c. These experiments demonstrated that the DT4-HTPG4 combination impeller enhanced enzyme production up to 23% compared with the DT4-DT4 combination at an aeration rate of 1 vvm and an agitation speed of 600 rpm. The main cause for this difference is thought to be a higher shear stress generated by the DT4-DT4 combination, which damages the mycelium of P. canescens and decreases xylanase production.  相似文献   

5.
The reaction of trimethylsilylcarbonamides with halogeno-diorganyl-boranes resp. trihalogenoboranes or organodihalogenoboranes gives monomeric resp. dimeric amidoboranes (borylcarbonamides) and derivatives of 4,8-diaza-1,5-dibora-2,6,9-trioxabicyclo[3.3.1]nonadienes. By reaction of the free acylamides with halogenoboranes in most cases the imide halides could be isolated as the only products. By reaction of the hydrochloride of bis(dimethylamino)-hydroxyborane withn-butyl-lithium followed by addition of the imide halides, the corresponding imidoylamines were formed.1H,11B, and19F-nmr spectra, mass spectra and characteristic ir group frequencies are reported.
15. Mitt.:W. Maringgele undA. Meller, Z. anorg. allg. Chem., im Druck.  相似文献   

6.
The reaction of phenalene with Cr(CO)3Py3/BF3·OEt2 afforded a mixture of two isomeric complexes, tricarbonyl(6a,7-9,9a,9b-·6-phenalene)chromium (1) and tricarbonyl(3a,6a,9b,4-6-·6-phenalene)chromium (2). Deprotonation of the mixture of compounds1 and2 followed by treatment with MeI, BunI, or D2O gave complexesexo-1-R-1 (3–5: R=Me (3), Bun (4), or D (5)). The molecular geometry of complex3 was established by X-ray structural analysis. Heating of complex5 in toluene or C6F6 at 90–110 °C resulted in redistribution of deuterium among positionsexo-1,endo-1, and 3 in the resulting complexes of types1 and2 via sigmatropic shifts of the H exo and H endo atoms in the nonaromatic ring as well asvia inter-ring migrations of the tricarbonylchromium group. In the case of3, the methyl label is distributed among positionsexo-1 and3 to form isomeric complexes with similar structures (exo-1-Me-2 (6), 3-Me-2 (7), and 3-Me-1 (8), respectively)via processes analogous to those observed in the case of isomerization of compound5 (except for migration of the H exo atom). The mechanisms of these rearrangements are discussed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1863–1880, October, 1997.  相似文献   

7.
The sodium salt of [B12H12]2− dianion reacts with carboxylic acid halides to give a mixture of B-acylated product [B12H11COR]2− and an unstable intermediate, the latter undergoing hydrolysis to form [B12H11OH]2−. The ratio of the products formed depends on the nature of the radical R. The reaction mechanism was studied by NMR spectroscopy. A number of novel [B12H11COR]2− compounds were synthesized; their structures were confirmed by NMR and IR spectral data. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 980–985, May, 1998.  相似文献   

8.
Summary The first synthesis ofthreo chalcone bromohydrins was realized by reaction oftrans chalcone epoxides with SnBr4 in molar ratios from 1:1 to 2:1. The compounds were obtained in high yields and isomeric purity. Their configuration was determined asthreo by different methods based on13C-NMR shifts of C- and C- atoms.
  相似文献   

9.
Comparative quantum chemical calculations of structural parameters, chemical shifts of 11B NMR spectra, and atomic charges in 10-vertex boron hydride anions [1-CB9H10] and [1-B10H9N2] were performed using the restricted Hartree-Fock method with the 6-31++G(D,P) basis set. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1853–1855, September, 2007.  相似文献   

10.
Summary The title compounds were prepared as follows:tert.-butyl-indane (10) was formylated to give a 72:28 mixture of the aldehydes23a and23b which were submitted to aKnoevenagel-Doebner condensation to afford the cinnamonic acids24. From the mixture, the pure stereoisomer24a was obtained by one crystallization in 57% yield. Its methylester27a could be quantitatively dealkylated to the methylester8 by treatment with AlCl3 in toluene. Cyclization to the indanone9 was then performedvia the propionic acid7 with polyphosphoric acid in 95% yield. From9 the carboxymethyl derivative30 was obtained by treatment with dimethylcarbonate and NaH. The second synthone 4-chlormethyl-indane (19) was prepared from the corresponding alcohol18 (in 82% yield) which in turn could be obtained from methylester17 by reduction with LiAlH4. The latter was accessible in 75% yield by dealkylation of ester13.
Herrn Prof. Dr.K. Kratzl mit besten Wünschen zum 80. Geburtstag gewidmet  相似文献   

11.
利用8-羟基喹啉原位反应,通过溶剂热方法制备出3种新颖的d~(10)配合物[M_2(HL)_3]NO_3·H_2O (M=Cd (1),Zn (2,3)),H_2L为1,1-(7,7′-二-(8-羟基喹啉))。单晶结构表明,3种配合物有着相同的带正电荷的结构单元[M_2(HL)_3]~+,但由于客体分子所处空间位置的不同表现为不同的空间结构,配合物1和3结晶于六方晶系(P6_3/m),配合物2结晶于三方晶系(R3)。中心金属离子以六配位的模式与来自HL-配体上的3个氧原子和3个氮原子形成一个轻微扭曲的八面体几何构型。存在于HL-配体与客体分子(NO_3~-,H_2O)间大量的弱作用力在结构空间堆积上起到了重要的作用。3种配合物均具有良好的热稳定性和绿色荧光发射性质。同时,通过从配合物1中提取出原位生成的配体H_2L,首次报道了其蓝色荧光发射性质。  相似文献   

12.
Mixed dialkytin(IV) trifluoroacetates,Me EtSn(O2CCF3)2,Et Pr n Sn(O2CCF3)2 andPr n Bu n Sn(O2CCF3)2 have been prepared by metathetical reactions of the corresponding dialkyltin(IV) chlorides with silver trifluoroacetate in CH2Cl2. They are monomeric in benzene and nonconducting inMeNO2 andMeCN. Bidentate trifluoroacetate groups are indicated by their IR spectra.Mössbauer spectra confirmtrans-arrangement of theR-Sn-R moiety.1H,19F NMR and mass spectra are also discussed.
Gemischte Dialkylzinn(IV)-trifluoracetate
Zusammenfassung Die gemischten Dialkylzinn(IV)-trifluoroacetateMe EtSn(O2CCF3)2,Et Pr n Sn(O2CCF3)2 undPr n Bu n Sn(O2CCF3)2 wurden über Metathese-Reaktionen der entsprechenden Dialkylzinn(IV)-chloride mit Silbertrifluoracetat in CH2Cl2 dargestellt. Sie sind monomer in Benzol und nichtleitend inMeNO2 undMeCN. Die IR-Spektren zeigen zweizähnige Trifluoracetat-Gruppen an. DieMössbauer-Spektren bestätigen dietrans-Anordnung derR-Sn-R-Einheit. Die1H-,19F-NMR und die Massenspektren werden ebenfalls diskutiert.
  相似文献   

13.
The synthesis and properties of [Ph 2 p-TolSi]2, [Ph 2 p-TolSi]2SiPh 2, [Ph 3 Si]2Si(p-Tol)2, [Ph 2 p-TolSi]2Si(p-Tol)2 and (SiPh 3)2SiH2 are described. The silanes are identified using IR,Ra- and29Si-NMR-spectroscopy.
  相似文献   

14.
Reaction of (RNPF3)2 compounds (R=CH3, C2H5,n-C3H7,n-C4H9,i-C4H9) withN-trimethylsilyl-methylamine leads to nucleophilic substitution of one or two fluorine atoms by the methylamino group, depending on the molar amounts of the reactants. In the case ofR=CH3, two by-products are formed: in the first step a compound with coordination numbers IV, V and VI for the three phosphorus atoms in C5H17F7N5P3 and in the second step a monospiroflourodiaza-5, 5-diphosphetidine.
9. Mitteilung:Utvary, K., Kubjacek, M., Varmuza, K. Z. anorg. allg. Chem.458, 281 (1979).  相似文献   

15.
Radiation chemical reactions ofOH, O•−, N3 and e aq t- witho- and m-hydroxycinnamic acids were studied. The second-orderrateconstantsforthereaction ofOH with ortho and meta isomers in buffer solution at pH7 are 3.9±0.2 × 109 and 4.4 ± 0.3 × 109 dm3 mol-1 s-1 respectively. At pH 3 the rate with the ortho isomer was halved (1.6 ± 0.4 × 109 dm3 mol-1 s-1) but it was unaffected in the case of meta isomer (k = 4.2±0.6 × 109dm3mol-1 s-1). The rate constant in the reaction of N3 with the ortho isomer is lower by an order of magnitude (k = 4.9 ± 0.4 × 108 dm3 mol-1s-1). The rates of the reaction of e aq t- with ortho and meta isomers were found to be diffusion controlled. The transient absorption spectrum measured in theOH witho-hydroxycinnamic acid exhibited an absorption maximum at 360 nm and in meta isomer the spectrum was blue-shifted (330 nm) with a shoulder at 390 nm. A peak at 420 nm was observed in the reaction of Obb−with theo-isomer whereas the meta isomer has a maximum at 390 and a broad shoulder at 450 nm. In the reaction of the absorption peaks were centred at 370–380 nm in both the isomers. The underlying reaction mechanism is discussed.  相似文献   

16.
A reaction of 10-R-substituted tetrahydrobenzo[b][1,6]naphthyridines (R = CN, CONH2, Me) with dimethyl acetylenedicarboxylate, methyl and ethyl propiolates, and acetylacetylene has been studied. It was found that 1-acryloyl-10-cyanotetrahydrobenzo[b][1,6]naphthyridines are the major products of the reaction of alkyl propiolates with 10-cyano-substituted naphthyridines, whereas the reaction with 10-carbamoyl-substituted naphthyridines gives a mixture of 1-acryloyl-substituted naphthyridines and hexahydrobenzo[b]pyrido[3,4,5-d,e][1,6]naphthyridines. The latter are the only products in the reaction of 10-carbamoyl-substituted naphthyridines with acetylacetylene. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1516–1527, July, 2008.  相似文献   

17.
利用高压容积法辅以卸压升温脱附排水法, 测定金属K修饰多壁碳纳米管对H2的吸附储存容量. 结果表明, 在室温(25 ℃), 7.25 MPa实验条件下, x%K0-MWCNTs (x%=30%~35%, 质量百分数)对H2的吸附储存容量可达3.80 wt%(质量百分数), 是相同条件下单纯MWCNTs氢吸附储量的2.5倍; 室温下卸至常压的脱附氢量为3.36 wt%(占总吸附氢量的~88%), 后续升温至673 K的脱附氢量为0.41 wt%(占总吸附氢量的~11%). 利用LRS和H2-TPD-GC/MS等谱学方法对H2/K0-MWCNTs吸附体系的表征研究表明, H2在K0-MWCNTs上吸附存在非解离 (即分子态)和解离(即原子态)两种吸附态; 在≤723 K温度下, H2/K0-MWCNTs体系的脱附产物几乎全为H2气; 723 K以上高温脱附产物不仅含H2, 也含有CH4, C2H4和C2H2等C1/C2-烃.  相似文献   

18.
The high-resolution207Pb magnetic resonance spectra ofR 4–n PbX n (R=Methyl, Ethyl;X=h1-Cyclopentadienyl, Chloride;n=1, 2) have been studied at 16.72Mc. The207Pb- ·· -1H spin-spin coupling constants for the molecules described have been obtained by analysis of the first order NMR-patterns as AxByM and AxByCzM respectively. The experimental spectra have been verified by a computer simulation. The chemical shifts and coupling constants of the lead organyls investigated show similar dependences on moleculare structure as well as number and species of the substituents like analogous organotin compounds.
  相似文献   

19.
Hydrogenation of 10H-indeno[1,2-b]quinoline in benzene in the presence of R2S7 gave 5,5a,10a,11-tetrahydro-10H-indeno[1,2-b]quinoline, the structure of which was established by mass-, IR, UV,13C, and1H NMR spectra. Thecis fusion of the indan and tetrahydroquinoline fragments, the axial orientation of the proton at C(5a), and the equatorial orientation of the proton at C(10a) were confirmed by molecular mechanics calculations using the PC MODEL program.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1098–1101, June, 1994.  相似文献   

20.
The synthesis and study (single crystal X-ray diffraction, thermogravimetry, IR- and NMR-spectroscopy) of a novel fluorozirconate LiK10Zr6F35·2H2O was performed. The structure of the compound is built from infinite chains [Zr6F35]11−, in which Zr-polyhedra are linked to each other through common edges and vertices. The chains are surrounded by K and Li cations and H2O molecules. The compound dehydration occurs in the temperature range 453–543 K with maximal rate at 528 K. It was established that zirconium polyhedra chain fragments underwent reorientational motion starting to influence 19F NMR spectra at temperatures higher than 270 and 180 K in LiK10Zr6F35·2H2O and LiK10Zr6F35, respectively. Above 450–420 K all fluorine sites in both samples participate in fluorine translational diffusion by at least two diffusion paths. Isotropic 19F NMR chemical shifts from different site types were detected by MAS NMR in the range 125–171 ppm.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号