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1.
《Solid State Sciences》2007,9(8):686-692
Hydrothermal reactions of 2-quinolinephosphonic acid (1) and CuSO4 or CdSO4 result in two new compounds with formula Cu(2-C9H6NPO3) (2) and Cd(2-C9H6NPO3)(H2O) (3). Compound 2 has a layer structure in which dimers of edge-sharing {CuO4N} square-pyramids are linked by {CPO3} tetrahedra through corner sharing. Compound 3 shows a new type of layer structure where chains of corner sharing {CdO5N} octahedra are connected by {CPO3} tetrahedra into an inorganic layer. The quinoline groups fill in the inter-layer spaces in both cases. Crystal data for 1: monoclinic, space group P21/c, a = 10.270(2) Å, b = 13.566(3) Å, c = 6.9818(16) Å, β = 101.916(4)°, V = 951.8(4) Å3, Z = 4. For 2: monoclinic, space group P21/c, a = 13.976(3) Å, b = 7.9398(18) Å, c = 7.8687(18) Å, β = 101.150(5)°, V = 856.7(3) Å3, Z = 4. For 3: monoclinic, space group P21/c, a = 17.164(4) Å, b = 5.4870(12) Å, c = 10.850(2) Å, β = 101.557(4)°, V = 1001.1(4) Å3, Z = 4. The magnetic measurement on 2 reveals a dominant antiferromagnetic exchange coupling between the Cu(II) centers. A quasi-reversible electrochemical reaction is observed for complex 2 immobilized on the surface of GC electrode, corresponding to the redox couple Cu2+/Cu+. The fluorescent properties of 1–3 are also investigated. 相似文献
2.
Erkan Ertürk 《Tetrahedron》2008,64(32):7555-7560
The cobalt(II) porphyrin complex (CoTPP) was found to be an efficient catalyst for the Wittig type olefination of acyl phosphonates with ethyl diazoacetate (EDA) in the presence of triphenylphosphine (Ph3P). By using this one pot methodology under mild conditions, densely functionalized vinyl phosphonates were obtained in high yields and high E/Z selectivities in relatively short reaction times. A rather broad substrate spectrum and steric influence on the reaction rate were observed. 相似文献
3.
Ahmed El-GokhaGerhard Maas 《Tetrahedron》2011,67(16):2849-2857
A diastereomeric mixture of dimethyl (2-formyl-2-methyl-1-phenylcyclopropyl)phosphonate ((Z)-6, (E)-6) was obtained by thermally induced cyclopropanation of α-methylacrolein with α-diazobenzylphosphonate 5. Application of proline or proline-derived organocatalysts accelerated the reaction, but had a minor effect on the Z/E ratio of 6. By reaction with benzylamine or methyl esters of glycine, (S)-alanine, and (S)-phenylalanine, the Z/E-mixture of 6 was converted into cyclopropylaldimines, which after reduction gave the corresponding N-substituted (2-aminomethyl-cyclopropyl)phosphonates. 相似文献
4.
A [3+2] cycloaddition of diethyl 1,2-oxiranephosphonate to aryl isocyanates catalyzed by lanthanide cations is described. The reaction is highly regioselective and 5-substituted 2-oxazolidinone phosphonates are obtained with a regioselectivity greater than 95:5 with respect to the 4-substituted regioisomer, and in up to 84% yield. When 20 mol % of Pybox-Yb3+ is used as a catalyst, enantiomerically enriched products are obtained in up to 75% ee, depending on the reaction conditions, and the nature of the isocyanate. Low temperatures benefit asymmetric induction, but have an adverse effect on the regioselectivity for para-substituted aryl isocyanates. 相似文献
5.
Ozlem SevenSidika Polat-Cakir Md. Shakhawoat HossainMustafa Emrullahoglu Ayhan S. Demir 《Tetrahedron》2011,67(19):3464-3469
The reactions of organoaluminum reagents (trimethylaluminum, triethylaluminum, etc.) with aryl and alkyl acyl phosphonates, which lead to the formation of α-hydroxy phosphonates in moderate to good yields, are reported. This method provides easy access to secondary and tertiary α-hydroxy phosphonates depending on the reaction conditions. The reactions of triethylaluminum with a series of acyl phosphonates at 0 °C gave the secondary α-hydroxy phosphonates, while at −100 °C they afford the tertiary α-hydroxy phosphonates. 相似文献
6.
Optically active α-substituted phenyloxyacetyloxy and aroyloxy phosphonates have been synthesized via catalytic asymmetric hydrogenation of the corresponding prochiral α,β-unsaturated phosphonates using Rh(I)/(R,R)-Me-DuPhos as the catalyst in methanol at 18 °C. The asymmetric hydrogenation reaction exhibits excellent enantioselectivity with enantiomeric excesses from 91 to 96%. 相似文献
7.
《Tetrahedron: Asymmetry》2014,25(22):1488-1493
The asymmetric cyclopropanation of a vinylphosphonate using optically active sulfonium and selenonium ylides derived from (−)-menthol and (+)-limonene was developed. The ylides were generated in situ by the reaction of the corresponding sulfonium or selenonium salt in the presence of potassium carbonate or DBU as a base. The transfer of the CHPh and CHCO2Et groups into the cyclopropane ring showed moderate diastereoselectivity and excellent enantioselectivity (up to 99:1) for the trans- and cis-products. The absolute configuration of phenyl cyclopropyl was assigned based on comparison to their tolyl analogues. 相似文献
8.
Najmedin Azizi 《Tetrahedron letters》2004,45(50):9233-9236
Under solvent-free reaction conditions and in the presence of solid LiClO4 a novel and mild protocol for the one-pot, three-component synthesis of primary α-amino phosphonates from an aldehyde, hexamethyldisilazane and a trialkyl phosphite is described giving high yields and having short reaction times. The same products are obtained in very low yields, when the three-component reaction is carried out under microwave irradiation and in the absence of solid LiClO4. Examples of some prepared 1-aryl-N,N′-bis(arylidene)methanediamines are also described. 相似文献
9.
Abbas Ali Jafari Sakineh Amini Fatemeh Tamaddon 《Journal of the Iranian Chemical Society》2013,10(4):677-684
The TfOH/C was readily prepared via simple absorption of triflic acid onto activated charcoal. This solid acid was used as an efficient catalyst for the synthesis of α-aminophosphonates through the Kabachnik–Fields reaction of carbonyl compound, amine and diethyl phosphite under solvent-free conditions. 相似文献
10.
Three bench-stable difluoromethylene phosphonate hydrazones were prepared from simple diethyl(difluoromethyl)phosphonate within two steps in good yields. The [3 + 2] cycloaddition reaction of these diazo precursors with aryl diazonium salts has been accomplished under metal-free conditions with exclusive regioselectivity. This transformation provides practical access to a broad panel of 2-aryl-2 H-tetrazol-5-yl difluoromethylene phosphonates, including the corresponding derivatives of amino acid... 相似文献
11.
Karel Pomeisl Marcela Krečmerová Radek Pohl Robert Snoeck Graciela Andrei 《Tetrahedron》2019,75(39):130529
With respect to the strong antiviral activity of (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-azacytosine various types of its side chain fluorinated analogues were prepared. The title compound, (S)-1-[3-fluoro-2-(phosphonomethoxy)propyl]-5-azacytosine (FPMP-5-azaC) was synthesised by the condensation reaction of (S)-2-[(diisopropoxyphosphoryl)methoxy)-3-fluoropropyl p-toluenesulfonate with a sodium salt of 5-azacytosine followed by separation of appropriate N1 and O2 regioisomers and ester hydrolysis. Transformations of FPMP-5-azaC to its 5,6-dihydro-5-azacytosine counterpart, amino acid phosphoramidate prodrugs and systems with an annelated five-membered imidazole ring, i.e. imidazo [1,2-a][1,3,5]triazine derivatives were also carried out. 1-(2-Phosphonomethoxy-3,3,3-trifluoropropyl)-5-azacytosine was prepared from 5-azacytosine and trifluoromethyloxirane to form 1-(3,3,3-trifluoro-2-hydroxypropyl)-5-azacytosine which was treated with diisopropyl bromomethanephosphonate followed by deprotection of esters. Antiviral activity of all newly prepared compounds was studied. FPMP-5-azaC diisopropyl ester inhibited the replication of herpes viruses with EC50 values that were about three times higher than that of the reference anti-HCMV drug ganciclovir without displaying cytotoxicity. 相似文献
12.
The versatile sulphonic acid group has been introduced into the family of interlamellar anchored materials. Zirconium bis-3-sulphopropylphosphonate is an example of an aliphatic acid. Zirconium bis-2-(sulphophenyl)ethylphosphonate is an example with an aromatic sulphonic acid group. In general, the sulphonic acids are not as crystalline as the carboxylic acid analogs. This is probably due to the relatively large size of the sulphonic acid group compared to the available cross sectional area of the layer face. The aliphatic compounds are more crystalline than the aromatics, as is expected from size considerations. The sulphonic acid group in both crystalline and semi-crystalline examples is accessible to reaction with bases. A few preliminary experiments have demonstrated the utility of these compounds as both strong acid ion exchangers and Bronsted acid catalysts. The layered sulphonic acid—zirconium 3-sulphopropylphosphonate—is thermally stable to well over 200°C. This indicates good potential for applications in Bronsted catalysis. This stability compares favorably with organic resin based sulphonic acids.The sulphonic acid class of interlamellar anchored materials have now been established. Both aliphatic and aromatic examples have been prepared. The utility of the sulphonic acids has been demonstrated with the typical reactions of this functional group. Specifically, the acids have been shown to be strong acid cation exchangers and a Bronsted acid catalyst. In addition, we have begun to develop an insight into the structural ramifications of these compounds. The size constraints of the zirconium phosphate type backbone are evident. Further, the thermal stability of this group of compounds is encouraging relative to its applications potential. 相似文献
13.
L. M. Pevzner 《Russian Journal of General Chemistry》2016,86(5):1046-1053
A series of furoyl phosphonates bearing methyl, methoxymethyl, and diethoxyphosphorylmethyl groups in the furan ring have been synthesized via the Arbuzov reaction from the corresponding acid chlorides. NMR spectral parameters of the prepared compounds were studied. The values of coupling constants between the phosphorus nuclei and the carbon nuclei of the furan ring have been examined with relation to the location of the acylphosphoryl group in the furan ring, the nature of second substituent, and location of the latter with respect to the phosphorus-containing substituent in the furan ring. The substitution in position 4 of the furan ring of 3-furoyl phosphonates has been shown to strongly decrease the value of the coupling constant between the phosphorus nucleus and the C2 atom of the heterocycle. The interaction between the phosphorus nuclei has not been detected in the spectra of the compounds containing both diethoxyphosphorylmethyl and acylphosphonate fragments. 相似文献
14.
Abstract Polymerizable amphiphilic organophosphorous compounds were synthesized and their self-aggregation behavior was investigated.
The studied molecules contain a hydrophilic phosphorus end group, an alkyl chain spacer with a variable length from 3 to 11
CH2 groups and a polymerizable methacrylic group at the other chain end. Thus, the molecules represent a class of polymerizable
surfactants. Two different reaction methods were used; either unsaturated alcohols or bromine-containing alcohols were applied
as starting compounds for the preparation of the organophosphorous surfactants. The self-aggregation and micelle formation
of the prepared compounds were investigated in aqueous solution by dynamic light scattering measurements. The critical micelle
concentration of the P-containing amphiphiles was in all cases smaller than 0.040 mol/l and strongly dependent on the polarity
of the phorphorous head group and the chain length of the spacer.
Graphical abstract
The synthesis of organophosphorous amphiphiles as surface active monomers for the modification of metal oxide surfaces is
presented. The spacer between the phosphorous head group and the methacrylate group was varied with regard to their length
and composition. The self-aggregation behavior of these methacrylate-functionalized phosphates and phosphonates surfactants
was investigated. 相似文献
15.
A variety of beta-keto phosphonates can be converted to gamma-keto phosphonates through reaction with ethyl(iodomethyl)zinc. The presence of alpha-alkyl substituents, Lewis basic functionality, and modestly acidic NH-protons are accommodated in substrates of this reaction. Chain extension of beta-keto phosphonates that contained olefinic functionality proceeded more quickly than cyclopropanation; however, it was not possible to effect the chain extension to the exclusion of cyclopropane formation. A primary reason for this imperfect chemoselectivity appears to be the slow chain extension of beta-keto phosphonates. Nevertheless, the simplicity, the scope, and efficiency of this method serve to make it an attractive alternative to the established methods for gamma-keto phosphonate formation. 相似文献
16.
Cycloaddition of diethyl 1-diazomethylphosphonate onto a CN double bond is described. It was found that the reaction of this phosphorus diazomethane with benzylidene-alkyl-amines resulted in the formation of (1-alkyl-5-phenyl-4,5-dihydro-1H-[1,2,3]triazol-4-yl)-phosphonic acid diethyl esters, whereas its reaction with methylene-aryl-amines, generated from the corresponding hexahydro-1,3,5-triazines, led to diethyl esters of (aziridin-2-yl)-phosphonic acid. 相似文献
17.
Mitsushiro Nomura Suguru Iida Kazunori Kobayashi Satoshi Horikoshi Toru Sugiyama Masatsugu Kajitani 《Journal of organometallic chemistry》2011,696(9):1723-4038
The aromatic [CpCo(S2C2(R)(H))] (R = Ph, Me, 9-phenanthryl, H) complexes reacted with N-halosuccinimides (NXS; X = Cl, Br, I) in carbon tetrachloride at room temperature to undergo the N-succinimide substitution reaction on the dithiolene ring, but no halogenated dithiolene complex was obtained. The imidation products [CpCo(S2C2(R)(N-sccinimide))] were yielded up to 64% where X = I and R = 9-phenanthryl. The reaction of [CpCo(S2C2(Ph)(H))] with N-bromophthalimide (NBP) also gave the imidation product [CpCo(S2C2(Ph)(N-phthalimide))]. This is the rare direct imidation reaction to an aromatic metallacycle by NXS. The reaction of [CpCo(S2C2H2)] (R = H) with NIS afforded the double imidation product. One by-product in this reaction was the dithiolene-dithiolene homo-coupling product [CpCo(S2C2(R))]2 (R = Ph, Me, 9-phenanthryl). The microwave-enhanced (MW) reactions were attempted in the carbon tetrachloride solution. Although the solution temperature increased up to only 43 °C by MW irradiation, the imidation reaction worked with short reaction time. 相似文献
18.
Yulia M. Sadykova Larisa M. Sadikova Alena V. Zalaltdinova Yulia K. Voronina Alexander R. Burilov Michael A. Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):705-710
AbstractThe reaction of 4-chloro- and 4-bromoresorcinol with 2-ethoxyvinylphosphonic acid dichloroanhydride has been investigated for the first time. It has been determined that the product of the reaction is the mixture of structural isomers of bicyclic phosphonates at the ratio of 9:1. The structure and composition of the compounds have been elucidated from 1H, 31P, and 13C NMR spectroscopy, mass-spectrometry (MALDI-TOF), as well as elemental and X-ray analysis. 相似文献
19.
The synthesis of glycosylphosphonates, isopolar, nonisosteric analogues of glycosylphosphates, from halonitro ethers, glycosyl acetates, or glycosyl trichloroacetimidates is reviewed. A new approach to phosphonate analogues of myo-inositol trisphosphate ( 50 ) is described. Based on a hypothetical reaction mechanism for the formation of thioethers from a glyoxalase I inhibitor, an advanced intermediate 59 for the synthesis of diphosphonate–phosphate analogues of 50 is obtained by an addition–elimination–addition sequence from 54 . Finally, glucosylphosphines, characterized as the corresponding phosphine oxides 61 and 62 have been prepared from the glycosylidene diazirine 60 , a precursor of the tetra-O-benzylglucopyranosylidene carbene. The phosphine oxides 61 and 62 were also obtained by reaction of the glycosyl acetate 18 with methyl diphenylphosphinite. 相似文献