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101.
Synthesis of 1,2-dihydroisoquinolin-1-ylphosphonates via CuI-catalyzed three-component tandem reactions of 2-(2-formylphenyl)ethanone, amine, and diethyl phosphite is described. The reactions proceed smoothly under mild conditions leading to the desired products in good yields. 相似文献
102.
Ir(III) metal complexes and related emitters bearing all kind of cyclometalated chromophoric chelates and non‐chromophoric ancillary are extensively studied during the past three decades. Many of them have been found to display bright room temperature phosphorescence from triplet excited states in both solution and solid states, offering a possible application in contemporary optoelectronic technologies, including organic light emitting diodes, electrochemiluminescence, biological imaging and chemical sensing. Among reported materials, there are Ir(III) complexes with at least one phosphorus (P)‐containing ligand and/or ancillary chelate, together with cyclometalates or equivalents that are in control of the actual emission energy. Particularly, possession of P‐based donor can lead to divergent structural and photophysical properties compared to the traditional designs. This review aims to provide a literature overview as well as the authors’ personal account to the development of relevant Ir(III) based phosphors bearing these P‐donors. To the readers’ convenience, the contents are subdivided into six sessions, according to whether or not they are charge natural, or with mono‐ or dianionic electronic character, and in accordance to their divergent bonding modes, i. e. monodentate, bidentate and tripodal coordination. In many cases, the P‐based ancillaries offer an easy accessible route to the formation of efficient sky‐blue and true‐blue emitters due to their π‐accepting property, together with enlarged emission energy gap and destabilized upper lying quenching state. 相似文献
103.
Guo‐Ming Wang Xiao‐Meng Zhao Xiao Zhang Zhen‐Zhen Bao 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(3):289-291
A new inorganic–organic hybrid zinc phosphite, [Zn(HPO3)(C6H11NO2)]n, has been synthesized hydrothermally. Protonated piperidin‐1‐ium‐4‐carboxylate (PDCA) was generated in situ by hydrolysis of the piperidine‐4‐carboxamide precursor. The P atom possesses a typical PO3H pseudo‐pyramidal geometry. The crystal structure features an unusual (3,4)‐connected two‐dimensional inorganic zinc–phosphite layer, with organic PDCA ligands appended to the sheets and protruding into the interlayer region. Helical chains of opposite chirality are involved in the construction of a puckered sheet structure. 相似文献
104.
V. A. Petrosyan E. E. Nifant M. E. Nryazymbetov R. K. Magdeeva N. S. Magomedova V. K. Bel My 《Russian Chemical Bulletin》1996,45(2):427-429
Benzylation ofcis2-hydro-2-oxo-4-methyl-1,3,2-dioxaphosphorinane in the electro-chemical version of the Michaelis-Becker reaction occurs stereospecifically with retention of the stereochemistry of the hydrophosphoryl center and affords stereochemically pure 2-benzyl-2-oxo-4-methyl-1,3,2-dioxaphosphorinane (yield 60–70 %). The structure of this compound was determined by X-ray diffraction analysis. The mechanism of the process was discussed.Translated fromIzvestiya Akademii Nauk. Seriva Khimicheskaya, No. 2, pp. 444–446, February, 1996. 相似文献
105.
K. Makuuchi F. Yoshii M. Kokuzawa Samantha Kulatunge Adul Thiangchanya 《Radiation Physics and Chemistry》1993,42(1-3)
A simple method was developed to evaluate the antioxidant activity for radiation vulcanized natural rubber latex. Tris(nonylated phenyl) phosphite has been selected as the effective antioxidant. This antioxidant is prone to hydrolyze under high humidity condition, resulting in the easy decomposition of radiation vulcanizate in the environment. 相似文献
106.
Ivan Zlatev 《Tetrahedron letters》2008,49(20):3288-3290
An efficient radical deoxygenation reaction of thiocarbonylimidazolyl activated glycoside analogue using dimethyl phosphite as hydrogen source and radical chain carrier was performed as a key step in a multi step synthesis towards a common 3-deoxy glycosyl donor for 3′-deoxynucleosides. This method has safety and cost advantages compared to the generally used radical reduction reagents. 相似文献
107.
Jarosław Lewkowski Anna Ignaczak Rafał Karpowicz Justyna Obiedzińska Maria Rodriguez-Moya 《Phosphorus, sulfur, and silicon and the related elements》2016,191(5):751-758
The addition of dimethyl phosphite to N,N'-terephthalylidene-alkyl- (or aryl-) amines resulted in new tetramethyl 1,4-phenylene-bis-(N-alkylaminomethyl)-phosphonates in moderate yields. The stereochemical behavior of these reactions was studied by NMR, demonstrating that the reactions lead to the formation of both possible diastereomeric forms from 1:1 to 1:2 ratios. This was unexpected considering that previously investigated additions of diethyl, dibenzyl, and diphenyl phosphites to terephthalaldimines were diastereoselective up to 100%. Attempts were made to find reasonable explanation for the phenomenon using semi-empirical and DFT calculations. 相似文献
108.
Seyed Mohammad Shoaei Hossein Aghaei Majid Monajjemi Mehran Aghaei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):652-660
The mechanism of electrochemical oxidation of catechol and some of its derivatives have been studied in the presence of triethyl phosphite as a nucleophile in aqueous solution. Voltammetric studies indicate that the quinones derived from catechol, and its derivatives, participate in Michael addition reaction with triethyl phosphite. The reaction mechanism consists of electron transfer followed by a chemical reaction which is named as an EC mechanism. The homogeneous rate constants (kobs) were estimated by comparing the experimental cyclic voltammograms with the digitally simulated voltammograms based on EC mechanism. Also the effects of nucleophile concentration and substituted group of catechols on voltammetric behavior and the rate constants of chemical reactions were examined. 相似文献
109.
制得了二丁胺甲基膦酸-亚磷酸氢锆Zr(HPO3)2-x.(O3PCH2NBu2).H2O(x=0.8,0.6,0.5,0.4,0.35),用溴化苄季铵化,得部分季铵化产物,溴化苄基二丁铵甲基膦酸-二丁胺甲基膦酸-亚磷酸氢锆Zr(HPO3)2-x.(O3PCH2NBu2)x-y.(O3PCH2N^+Bu2.CH2Ph.Br^-).H2O(y<x),用作相转移催化剂,对液/液或固/固/液相转移催化的取 相似文献
110.
Chin-Ping Yang Jiun-Hung Lin 《Journal of polymer science. Part A, Polymer chemistry》1995,33(14):2425-2433
Fifteen bis(phenoxy) fluorene-containing poly(amide-imide)s III were synthesized by the direct polycondensation of 9,9-bis[4-(4-aminophenoxy)phenyl]fluorene (BAPPF) with var-ious aromatic bis(trimellitimide)s II in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s III having inherent vis-cosities up to 1.45 dL/g were obtained in quantitative yields. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 263–315°C and the 10% weight loss temperatures were above 510°C in nitrogen. Some properties of poly(amide-imide)s III were compared with those of the corresponding isomeric poly(amide-imide)s III ′ prepared from 9,9-[4-(4-trimellitimidophenoxy)phenyl]fluorene and various aromatic diamines. © 1995 John Wiley & Sons, Inc. 相似文献