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1.
Ludger Ernst 《Magnetic resonance in chemistry : MRC》1977,9(1):35-43
13C chemical shifts and 31P? 13C spin–spin coupling constants are reported for 10 alkyl-, 20 benzyl- and 3 (naphthylmethyl)-phosphonates. While in saturated aliphatic chains P–C couplings over more than four bonds cannot be resolved, couplings over up to seven bonds are observed in the benzyl type systems. Conformational and substituent effects on J(PC) are studied and discussed. nJ(PF) (n = 4, 5, 6) are reported for the isomeric (fluorobenzyl)phosphonates and nJ(PP) (n = 5, 6, 7) were obtained from the 13C satellites in the 31P n.m.r. spectra of the isomeric diphosphonates, C6H4[CH2P(O)(OEt)2]2. Comparison of those 13C absorptions of the latter, which represent the X parts of ABX or AA′X spin systems, with the spectra of the corresponding (methylbenzyl)phosphonates, CH3C6H4CH2P(O)(OEt)2, yielded the relative signs of nJ(PC) (n = 2–6). 相似文献
2.
The 1H NMR spectral analysis of four 8-membered rings, 2-thioxo- (or 2-oxo-) 2-R-1,3,6,2- trithiaphocane, is reported. The stereochemistry of the 8-membered ring is discussed. The 31P NMR spectral parameters [δ31P, 1J(PC)] obtained on several cyclic 1,3,2-dithiaphospha compounds of variable size (5, 6, 8, 12 and 16-membered rings) are discussed as a function of the ring size and of the geometry of the molecule. 相似文献
3.
The vicinal couplings of ring hydrogens to methyl C atoms (3JCH3H) in 22 methyl substituted non-benzenoid polycyclic conjugated hydrocarbons have been determined from the undecoupled 13C NMR spectra and have been correlated with bond lengths as well as with the corresponding vicinal H,H couplings, which are taken partly from own 1H NMR analysis and partly from literature. As a result the (3JCH3H) couplings of sterically unperturbated methyl groups in 7-membered rings are proportional to the corresponding 3JHH values which is indicative of comparable influences, but both types of vicinal couplings are not dependent on bond lengths only. Moreover they are to a large extent determined by the CCH bond angles θ and θ', which show a significant variation in condensed 7-membered rings so that this twofold dependence has to be taken into account for structure determinations. 相似文献
4.
The behaviour under electron impact (70 eV) which includes some rearrangement processes of some tetraorganodiphosphanedisulfides R2P(S)-P(S)R2 (R ? CH3, C2H5, n-C3H7, n-C4H9, C3H5, C6H5) and CH3RP(S)–P(S)CH3R (R ? C2H5, n-C3H7, n-C4H9, C6H5, C6H5, C6H5,CH2) is reported and discussed. Fragmentation patterns which are consistent with direct analysis of daughter ions and defocusing metastable spectra are given. The atomic composition of many of the fragment ions was determined by precise mass measurements. In contrast to compounds R3P(S) loss of sulphur is not a common process here. The first step in the fragmentation of these compounds is cleavage of one P–C bond and loss of a substituent R?. The second step is elimination of RPS leading to [R2PS]+ from which the base peaks in nearly all the spectra arise. The phenyl substituted compounds give spectra with very abundant [(C6H5)3P]+. and [(C6H5)2CH3P]+. ions respectively, resulting from [M]+. by migration of C6H5. Rearrangement of [M]+. to a 4-membered P-S ring system prior to fragmentation is suggested. 相似文献
5.
《Journal of Coordination Chemistry》2012,65(23):4098-4107
A macrocyclic hexanuclear iron(III) 18-metallacrown-6 complex, [Fe6(C9H6BrN2O3)6(CH3OH)4(H2O)2]?·?7CH3OH?·?4H2O, has been prepared using a trianionic pentadentate ligand N-acetyl-5-bromosalicylhydrazidate, abshz3–, and characterized by X-ray diffraction. The crystal structure contains a neutral 18-membered metallacrown ring consisting of six Fe(III) and six abshz3– ligands. The 18-membered metallacrown ring is formed by combination of six structural moieties, [Fe(III)–N–N]. Due to meridional coordination of ligand to Fe3+, the ligand enforces the stereochemistry of the Fe3+ ions as a propeller configuration with alternating Δ/Λ forms. Methanol and water are linked with Fe1, Fe1A, Fe,3 and Fe3A. The ratios of methanol to water are 0.76?:?0.24 for Fe1 and Fe1A, and 0.30?:?0.70 for Fe3 and Fe3A, which results in four component crystals of metallacrown rings with ratio of 0.168?:?0.072?:?0.532?:?0.228. Antibacterial screening data showed that the iron metallacrown has moderate antimicrobial activity against Bacillus subtilis. 相似文献
6.
M. Z. Kassaee M. R. Momeni F. A. Shakib M. Ghambarian S. M. Musavi 《Structural chemistry》2009,20(3):517-524
Biologically important bicyclic species, including 6H-, 6H-6-aza-, and 6-oxabenzocycloheptatrienes (in which the benzene moiety is fused meta with respect to the tetrahedral constituents: –CH2–, –NH–, and –O–, respectively), show strong shifts of tautomerizations in favor of the corresponding tricyclic benzonorcaradienes
(with ΔH values of −11.49, −14.55, and −19.20 kcal mol−1, respectively), at B3LYP/6-311++G**//B3LYP/6-31G*, and MP2/6-311++G**//MP2/6-31G* levels, and at 298 K. In contrast, such
shifts are strongly disfavored by the isomeric bicyclic species in which the benzene moieties are fused ortho or para with respect to –CH2–, –NH–, and –O–, respectively. Hence for species with ortho benzene rings including 5H-, 5H-5-aza- and 5-oxabenzocycloheptatrienes, tautomerization ΔH values are 30.76, 31.89, and 25.27 kcal mol−1, respectively, while for species with para fused benzene moieties including 7H-, 7H-7-aza-, and 7-oxabenzocycloheptatrienes, tautomerization ΔH values are 24.12, 26.00, and 19.55 kcal mol−1, respectively. NICS calculations are successfully used to rationalize these results. The calculated energy barriers for inversion
of the seven-membered rings of bicyclic species predict a dynamic nature for all the structures except for the virtually planar
6H-6-aza- and 6-oxabenzocycloheptatrienes. Finally, our theoretical data are compared to the experimental results where available.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
Jasim M. A. Al-Rawi M. A. Sheat Nacur Ayed 《Magnetic resonance in chemistry : MRC》1984,22(5):336-339
Carbon-13 chemical shifts and 2J(POC), 3J(POCC), 2J(PNC) and 3J(PNC) coupling constants of 30 compounds containing the amine moiety, with the general formula Y2PNRR' (Y ? C6H5, CH3O, CH3CH2O, CH2O; Y2 ? 1,2-dioxybenzene) have been determined. J(PNC) values have been used to explain the preferred conformation around the P? N bond. A comparison between 2J(PNC) and 2J(PNH) was accomplished. 相似文献
8.
Harald Günther Hans Schmickler Maria-Eugenia Günther Dieter Cremer 《Magnetic resonance in chemistry : MRC》1977,9(7):420-425
It is shown that sterically unperturbed vicinal HH coupling constants in planar 7-membered π-systems correlate linearly with the HMO π-bond order: 3J(HH) = 20.91Pμ,ν–3.85 (r.m.s. error 0.26 Hz, correlation coefficient =0.988). Systematic deviations from this relationship which most probably originate from valence angle changes are found for fused π-systems containing rings of different size. Model calculations using the CNDO/2 method as well as finite perturbation theory and INDO wave functions support the experimental findings. An improvement of existing 3J(HH)? Pμ,ν correlations for planar 6-membered rings is possible if CNDO/2 π-bond orders are used instead of HMO or PPP-SCF data. 相似文献
9.
All J(P? H) and J(P? C) values, including signs, have been obtained in acetylenic and propynylic phosphorus derivatives, R2P(X)? C?C? H and R2P(X)? C?C? CH3 (X ? oxygen, lone pair and R ? C6H5, N(CH3)2, OC2H5, N(C6H5)2, Cl) from 1H and 13C NMR spectra. In PIV derivatives the following signs are obtained: 1J(P? C)+, 2J(P? C)+, 3J(P? C)+, 3J(P? H)+, 4J(P? H)? . Linear relations are observed between 1J(P? C), 2J(P? C) and 3J(P? C) versus 3J(P? H), indicating that these coupling constants are mainly dependent on the Fermi contact term, though the other terms of the Ramsey theory do not seem to be negligible for 1J(P? C) and 2J(P? C). In PIII derivatives these signs are: 1J(P? C)- and +, 2J(P? C)+, 3J(P? C)-, 3J(P? H)-, 4J(P? H)+. Only 3J(P? C) and 3J(P? H) reflect a small contribution of the Fermi contact term while in 1J(P? C) and 2J(P? C) this contribution seems to be negligible relative to the orbital and/or spin dipolar coupling mechanisms. 相似文献
10.
Contributions to the Chemistry of Phosphorus. 167. Constitutional and Configurational Isomers of Pentaphosphane(7), P5H7 Phosphane mixtures containing 10—15 P-% of pentaphosphane(7), P5H7, are obtained by thermolysis of diphosphane, P2H4, or as residue from distillation of crude diphosphane [3]. According to the complete analysis of the 31P{1H}-NMR spectrum on the basis of selective population transfer experiments, P5H7 exists as a mixture of three diastereomers of n-P5H7 — 1a (erythro, erythro), 1b (erythro, threo), 1c (threo, threo) — and of the constitutional isomer 2-phosphinotetraphosphane 2 (iso-P5H7, largest relative isomeric abundance). The correlation between the diastereomers and the observed spin systems results from the preferred gauche orientation of neighboring free electron pairs, the dependence of 1J(PP) on dihedral angles, and the 3J(PP) long range couplings. From the 31P-NMR data of the phosphane molecules PnHn+2 with n = 1—5 general relationships for the δ(31P) values and the 1J(PP) coupling constants of chain-type phosphorus hydrides as a function of their structural parameters are derived. 相似文献
11.
Khodayar Gholivand Nilufar Dorosti Fatemeh Ghaziany Manouchehr Mirshahi Sina Sarikhani 《Heteroatom Chemistry》2012,23(1):74-83
A new series of N‐phosphinylureas 5b, 6a–7c was synthesized and characterized by 1H, 13C, 31P NMR, IR, and elemental analysis. The three‐dimensional structure of 5b has been determined by X‐ray crystallography. The crystal structure revealed the existence of four independent molecules. All structures form two chains with different arrangements and connect to each other via hydrogen bonds to produce two‐dimensional polymeric chains. The cytotoxicity of cyclophosphamide (a standard antitumor compound) and its nine analogues with formula R1C6H4 NHC(O)NHP(O)XCH2C(R2)2 CH2Y(X = Y = NH, R2 = CH3, R1 = H ( 5a ), CH3 ( 5b ), NO2 ( 5c ), X = O, Y = NH, R2 = H, R1 = H ( 6a , CH3 ( 6b ), NO2 ( 6c ), and X = Y = O, R2 = CH3, R1 = H ( 7a ), CH3 ( 7b ), NO2 ( 7c )) as well as phenyl urea were evaluated in vitro against three human tumor cell lines K562, MDA‐MB‐231, and HepG2. The results showed that most of the compounds have significant activity against the selected cell lines. Also, HepG2 cells were more sensitive to all the tested compounds than other cell lines. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:74–83, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20754 相似文献
12.
Ludwig Maier 《Helvetica chimica acta》1969,52(3):858-871
Tris-chloromethyl-phosphine oxide, (ClCH2)3 P?O(I), is obtained by chlorination of (HOCH2)3P?O with PCl5 or (C6H5)3PCl2, and also by oxidation of (CICH2)3P?O and (ClCh2)2(CH3)P?O. High yields of tris-(dialkyloxyphosphonly-methyl)-phosphine oxides, [RO2(O)PCH2]2P?O (II) (R?CH3, C2H5, iso-C3H7, n-C4H9, 2- ethyl-hexyl), tris (alkyloxyphosphinyl-methyl)-phosphine oxides, [R2(O)PCH2]3P?O(R = C6H5, CH3) are obtained by heating tris-chloromethyl-phosphine oxides, [(RO) (R′) (O)PCH2]3P?O (R = C4H9, R′? C6H5) and tris-(oxophosphoranyl-phosphine oxides with phosphites, phosphonites and phosphinites, respectively, at 170–180°C for several hours. Compounds II possess an extraordinarily high absorption capacity. Thus a warm. 2% solution of II (R = C2H5) in benzene solidifies completely on cooling so that no benzene can be poured off. Tris-dihydroxyphosphonyl-methyl)-phosphine oxide, [(HO)2(O)PCH2]3P?O, obtained by hydrolysis of II (R ? C2H5) with refluxing conc. HCl or by thermal decomposition of II (R ? iso-C3H7) at 190°, titrates in aqueous solution as a hexabasic acid with breaks at pH = 4,4 (three equivalents) and pH = 10,7 (three equivalents). It forms crystalline salts with amines, alkali and alkaline earth metals, and is an excellent chelating agent. The 1H- and 31?P-NMR. spectra of all the compounds prepared are discussed. 相似文献
13.
Kwok W. Chiu Henry S. Rzepa Richard N. Sheppard Geoffrey Wilkinson Wai-Kwok Wong 《Polyhedron》1982,1(11-12)
Neutral mononuclear tertiary phosphine rhodium(I) complexes of the formula RhX(PMe3)(dppm), X = Cl, CH2SiMe3, CH2CMe3, CH2CMe2Ph, η5-C5H5, DPPM = bis(diphenylphosphino)methane, RhCl(PPh3)(dppm), RhX(dppm)2, X = Cl, Me and Rh(η5-C5H5(dppm) have been synthesised. In Rh(η5-C5H5)(PMe3)(dppm), the dppm ligand is unidentate according to 31P{1H} NMR and X-ray data.The 31P{1H} NMR spectral parameters of RhX(PR3)(dppm) have been determined by a combination of two dimensional δ/J resolved spectroscopy and heteronuclear nuclear Overhauser effect difference spectroscopy (NOEDS) in conjunction with iterative analysis of the one dimensional spectra. 相似文献
14.
《Journal of Coordination Chemistry》2012,65(19):3142-3156
Five new coordination compounds, {[Mn(L)(CH3OH)2] · CH3OH · H2O} n (1), {[Cd(L)(DMF)2(H2O)] · H2O} n (2), {[Co(L)(CH3OH)4] · CH3OH}2 (3), {[Cd(L)(phen)(CH3OH)] · CH3OH} n (4), and {[Mn(L)(phen)(H2O)] · CH3OH} n (5) (L = 5-ferrocene-1,3-benzenedicarboxylic acid, phen = 1,10-phenanthroline) were obtained from different metal salts and L with or without 1,10-phen under mild conditions. Complex 1 is a 1-D ladder-like chain composed of 8-membered rings A and 16-membered rings B, which arrange alternately. Complex 2 is an infinite linear chain, further bridged to form a parallel double chain through different hydrogen-bond interactions. Complex 3 is a discrete dinuclear structure, while 4 is a neutral 1-D infinite zigzag coordination chain. Complex 5 is a 1-D linear chain with phen and ferrocene groups of L as pendants hanging on the different sides of the main chain. Variable temperature magnetic susceptibilities of 1 were measured and weak antiferromagnetic exchange interactions between the neighboring Mn(II) ions were found with J = ?0.95 cm?1. 相似文献
15.
15N-NMR. parameters for the complexes trans-[MCl2 (15NH2 (CH2)5CH3)L] are reported; M = Pt, Pd, L = PBu, PMePh2, P (p-CH3? C6H4)3, AsBun3, AsMePh2, As (p-CH3C6H4)3, NH2 (CH2)5CH3 and (for Pt) C2H4. For both metals, the NMR. parameters depend on the trans-influence of the ligand L. The values 1J (195Pt, 15N) vary from 138 to 336 Hz and can be shown to correlate with the values 1J (195Pt, 31P) in the complexes trans-[PtCl2 (PBu)L]. There is a linear relation between the 15N chemical shifts in the complexes of the two metals. The reactions of the complexes sym-trans-[M2Cl4L2], M = Pd, Pt, L = a tertiary phosphine or arsine, with neutral ligands are described. 195Pt-, 31P- and 13C-NMR. data are reported. 相似文献
16.
Synthesis,Spectroscopy, X‐ray Crystallography,and DFT Computations of Nanosized Phosphazenes
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Zahra Shariatinia Elnaz Jalali Moghadam Narges Maghsoudi Hourieh Sadat Mirhosseini Mousavi Michal Dusek Vaclav Eigner 《无机化学与普通化学杂志》2015,641(5):967-978
Nanoparticles of nine phosphazenes with general formula 4‐CH3C6H4S(O)2N=PX3 [X = Cl ( A ), NC4H8 ( 1 ), NC6H12 ( 2 ), NC4H8N–C(O)OC2H5 ( 3 ), NC4H8N–C(O)OC6H5 ( 4 ), NC4H8O ( 5 ), NHCH2–C4H7O ( 6 ), N(CH3)(C6H11) ( 7 ), NHCH2–C6H5 ( 8 ), and 2‐NH‐NC5H4 ( 9 )] were synthesized using ultrasonic method and characterized by 1H, 13C, 31P NMR, FT‐IR, fluorescence, as well as UV/Vis spectroscopy and additionally with XRD, FE‐SEM, N2 sorption, and elemental analysis. The 31P NMR spectra of compounds 1 – 9 reveal the most up field shift δ(31P) for 9 at –11.45 ppm reflecting the most electron donation of 2‐aminopyridinyl rings through resonance to the phosphorus atom. The 1H, 13C NMR spectra of 7 exhibit two sets of signals for the hydrogen and carbon atoms of its two isomers present in the solution state in 1:4 ratio. The FE‐SEM micrographs illustrate that the nanoparticles of compounds 1 – 9 have spherical morphology and a size of 27–42 nm. From the XRD patterns, the crystal sizes were estimated to about 24–86 nm. The highest bandgap was measured for 3 (3.81 eV) whereas the smallest was measured for 8 (3.50 eV). The structures of two polymorphs of compound 5 ( 5 , 5′ ) were determined by X‐ray crystallography at 120 K. Both of these polymorphs are triclinic with P1 space group but 5 has a doubled unit cell volume and two symmetrically independent molecules ( 5a and 5b ). In structures 5a and 5′ , the phosphorus and all endocyclic atoms of two morpholinyl rings display disorder, whereas the molecule 5b does not show disorder. The strong intermolecular O–H ··· O hydrogen bonds plus weak intermolecular C–H ··· O and C–H ··· N interactions create three‐dimensional polymers in the crystalline networks of 5 and 5′ . The DFT computations illustrate that molecule 5b is more stable than 5a by –1.1062 and –0.9779 kcal · mol–1 at B3LYP and B3PW91 levels, respectively. The NBO calculations presented sp3d hybridization for phosphorus and sulfur atoms and sp2, sp3 hybrids for the nitrogen and oxygen atoms. 相似文献
17.
W. McFarlane 《Magnetic resonance in chemistry : MRC》1969,1(1):3-9
19F and 31P decoupling experiments are used to simplify the proton spectra of para-substituted derivatives of triphenyl phosphine, prior to 1H-{1H} tickling experiments. 3J(31P…?H) and 4J(31P…?H) are positive, and 5J(31P…?19F) is negative in the trivalent phosphorus derivatives, and all become more positive as the valency of the phosphorus atom is increased. A triple resonance experiment is used to show that 7J(31P…?H) in [p-CH3C6H4CH2P⊕(C6H5)3] is negative. The double resonance technique is used to relate the 31P chemical shifts to the tetramethylsilane resonant frequency. 相似文献
18.
《Journal of Inorganic and Nuclear Chemistry》1977,39(3):499-511
The synthesis of phosphorylacetic acids, RR′P(O)CH2COOH, where R = C6H5 and R′ = OC2H5, C2H5, i-C3H7, n-C4H9, sec-C4H9 and C6H5, from the appropriate phosphinous acids, several of which are previously unreported, is discussed. 31P nuclear magnetic resonance spectra are reported for the phosphinous acids, RR′P(O)H, the phosphorylacetic acids and the metal derivatives of the phosphinous acids, RR′POM, where M in Na or MgBr, which are intermediates in the synthesis. The diastereoisomers of Phsec-BuP(O)H exhibit different 31P NMR spectra. Diastereotopic protons of the phosphinous acids and phosphorylacetic acids do not exhibit complex PMR spectra, whereas the diastereotopic methyl groups of the isopropyl compounds do. Some metal complexes of the phosphorylacetic acids are reported. 相似文献
19.
Tri(1‐cyclohepta‐2, 4, 6‐trienyl)phosphane, P(C7H7)3 ([P] when coordinated to a metal atom), was used to stabilize complexes of platinum(II) and palladium(II) with chelating dichalcogenolato ligands as [P]M(E∩E) [E = S, ∩ = CH2CH2, M = Pt ( 3a ); E = S, ∩ = 1, 2‐C6H4, M = Pt ( 5a ), Pd ( 6a ); E = S, ∩ = C(O)C(O), M = Pt ( 7a ), Pd ( 8a ); E = S, Se, ∩ = 1, 2‐C2(B10H10), M = Pt ( 9a, 9b ), Pd ( 10a, 10b ); E = S, ∩ = Fe2(CO)6, M = Pt ( 11a ), Pd ( 12a )]. Starting materials in all reactions were [P]MCl2 with M = Pt ( 1 ) and Pd ( 2 ). Attempts at the synthesis of [P]M(ER)2 with non‐chelating chalcogenolato ligands were not successful. All new complexes were characterized by multinuclear magnetic resonance spectroscopy in solution (1H, 13C, 31P, 77Se and 195Pt NMR), and the molecular structures of 5a and 12a were determined by X‐ray analysis. Both in the solid state and in solution the ligand [P] is linked to the metal atom by the P‐M bond and by η2‐C=C coordination of the central C=C bond of one of the C7H7 rings. In solution, intramolecular exchange between coordinated and non‐coordinated C7H7 rings is observed, the exchange process being markedly faster in the case of M = Pd than for M = Pt. 相似文献
20.
Zhang Zhengping Gorman B.P. Dong Hanjiang Orozco-Teran Rosa A. Mueller D.W. Reidy R.F. 《Journal of Sol-Gel Science and Technology》2003,28(2):159-165
Dimethyldiethoxysilane (DMDES) appears to be a very promising modifier to introduce functional groups to a silicate network. The polymerization and cyclization of DMDES under acid-catalyzed conditions (DMDES : Ethanol : water : HCl = 1:4:4:3.68 × 10–4 in molar ratio) were investigated by high resolution liquid 29Si nuclear magnetic resonance (NMR) and Fourier transform infrared spectrometry (FTIR). Time-dependent NMR and FTIR data illustrate that monomers of (CH3)2Si(OC2H5)2, (CH3)2Si(OC2H5)(OH), and (CH3)2Si(OH)2 reach meta-equilibrium in less than 4 minutes. 3-membered rings ((CH3)2SiO)3 appear about half an hour later and 4-membered rings ((CH3)2SiO)4 an hour later, which continue to be formed over 24 hours. The relative concentrations of monomers, linear structures and cyclic structures suggest a modified model for the kinetics of cyclization, where 4-membered rings are formed by dimer-dimer interactions, as opposed to monomer-trimer interactions previously proposed. 相似文献