Fe3O4@Propylsilane@Histidine[HSO4‐] magnetic nanocatalysts: Synthesis,characterization and catalytic application for highly efficient synthesis of xanthene derivatives

The surface of Fe₃O₄ magnetic nanoparticles (MNPs) was modified by chloropropylsilane and histidine. The imidazole group of prepared Fe₃O₄@Propylsilane@Histidine MNPs converted to imidazolium hydrogen sulfate group and Fe₃O₄@Propylsilane@Histidine [HSO₄^‐] as a novel environmentally friendly ionic liquid/ magnetite nanoparticle was prepared, successfully. FT‐IR, XRD, SEM and TEM instruments was used to identifiy the histidine ionic liquids/magnetite nanoparticles (HILMNPs). The catalytic activity of synthesized HILMNPs was appraised for the synthesis of 9‐aryl‐1,8‐dioxooctahydroxanthene and spiro[indoline‐3,9′‐xanthene]trione derivatives. The activity of HILMNPs was much better than the other reported heterogeneous and homogeneous catalysts. Furthermore, the prepared catalyst could be separated from the reaction mixture and reused four times without any significant loss in its activity.     

Ammonium Chloride–Catalyzed One-Pot Synthesis of Tetrahydrobenzo[α]xanthen-11-one Derivatives Under Solvent-Free Conditions

A one-pot, multicomponent reaction of aldehydes, dimedone, and β-naphthols is described for the preparation of 12-aryl- or 12-alkyl-8,9,10,12-tetrahydrobenzo[α]xanthen-11-one derivatives using ammonium chloride as a mild, inexpensive, and environmentally benign catalyst under solvent-free conditions. Different types of aldehyde and β-naphthol derivatives are used in the reaction, and in all cases the products were synthesized successfully.

Rearrangement of Aryl Geranyl Ethers

This article describes the thermal rearrangement reactions of aryl geranyl ethers. These reactions depend on the structure of the aryl moiety of the substrate and the reaction conditions used. The naphthyl ethers underwent a [1,3]-alkyl shift, followed by acid-catalyzed intramolecular cyclization. The microwave-assisted rearrangement of isoquinolinyl ether showed a pattern of an abnormal Claisen rearrangement. The multi step rearrangement of the quinolyl ether afforded a spiro compound. These new reactions were used to synthesize novel heterocyclic compounds.     

A Novel Potentiometric Sensor for Thiocyanate Based on an Amide‐Linked Manganese Diporphyrin Xanthene

The synthesis of a new compound, amide‐linked manganese diporphyrin xanthene (Mn₂Cl₂ADPX), and its application for preparation of thiocyanate selective electrodes was described. The electrode was prepared with a PVC membrane combining Mn₂Cl₂ADPX as an electro active material, 2‐nitrophenyl octyl ether (o‐NPOE) as a plasticizer in the percentage ratio of 3 : 65 : 32 (Mn₂Cl₂ADPX: o‐NPOE: PVC, w : w : w). The electrode exhibited linear response within the concentration range of 2.4×10^?6 to 1.0×10^?1 M SCN^?, with a working pH range from 3.0 to 8.0 and a fast response time of less than 60 s. Several electroactive materials and solvent mediators have been compared and the experimental conditions were optimized. The Mn₂Cl₂ADPX based electrode shows obviously better response characteristics than that of monoporphyrin manganese in terms of working concentration range and slope. Selectivity coefficients for SCN^? relative to a number of interfering ions were investigated. The electrode exhibits anti‐Hofmeister selectivity toward SCN^? with respect to common coexisting anions. The electrode was applied to the determination of SCN^? in body urine with satisfactory results.     

Recent advances in phosphorus-carbon bond formation: synthesis of H-phosphinic acid derivatives from hypophosphorous compounds

This account summarizes the research conducted in our laboratory over the past five years. New methodologies were devised for the formation of P-C bonds with a focus on the reactions of hypophosphorous acid derivatives. Three types of reactions have been developed: palladium-catalyzed cross-coupling, room-temperature radical addition, and palladium-catalyzed addition. Our results are summarized in each of these areas and include some of our most recent data. (1) Our palladium-catalyzed cross-coupling has been extended to the direct coupling of alkyl phosphinates with a variety of aryl, heteroaryl, and even alkenyl electrophiles. (2) The addition of sodium hypophosphite under radical conditions is extended from alkenes to alkynes. (3) The catalytic addition of hypophosphorous compounds using palladium catalysts (hydrophosphinylation) is also discussed.     

呫吨染料合成方法研究进展

呫吨染料是一类重要荧光染料,其良好的光物理性质使其得到了广泛应用。呫吨染料一般通过富电子的间苯二酚(或间氨基苯酚)与邻苯二甲酸酐在酸催化条件下缩合得到。近年来,呫吨染料在生物显微成像领域获得广泛应用,染料结构也日趋复杂,传统的合成方法不能满足需要,因而不断有新的呫吨染料合成方法见诸文献。本文简要概述了既有呫吨染料合成路线,并分析讨论了各方法的优缺点及适用底物范围。     

A new phosphorescent heteroleptic cuprous complex with a neutral 2‐methylquinolin‐8‐ol ligand: synthesis,structure characterization,properties and TD–DFT calculations

Luminescent Cu^I complexes have emerged as promising substitutes for phosphorescent emitters based on Ir, Pt and Os due to their abundance and low cost. The title heteroleptic cuprous complex, [9,9‐dimethyl‐4,5‐bis(diphenylphosphanyl)‐9H‐xanthene‐κ²P ,P ](2‐methylquinolin‐8‐ol‐κ²N ,O )copper(I) hexafluorophosphate, [Cu(C₁₀H₉NO)(C₃₉H₃₂OP₂)]PF₆, conventionally abbreviated as [Cu(Xantphos)(8‐HOXQ)]PF₆, where Xantphos is the chelating diphosphine ligand 9,9‐dimethyl‐4,5‐bis(diphenylphosphanyl)‐9H‐xanthene and 8‐HOXQ is the N ,O‐chelating ligand 2‐methylquinolin‐8‐ol that remains protonated at the hydroxy O atom, is described. In this complex, the asymmetric unit consists of a hexafluorophosphate anion and a whole mononuclear cation, where the Cu^I atom is coordinated by two P atoms from the Xantphos ligand and by the N and O atoms from the 8‐HOXQ ligand, giving rise to a tetrahedral CuP₂NO coordination geometry. The electronic absorption and photoluminescence properties of this complex have been studied on as‐synthesized samples, whose purity had been determined by powder X‐ray diffraction. In the detailed TD–DFT (time‐dependent density functional theory) studies, the yellow emission appears to be derived from the inter‐ligand charge transfer and metal‐to‐ligand charge transfer (M +L ′)→LCT excited state (LCT is ligand charge transfer).     

9, 9-二(3-氨基-4-羟基苯基)呫吨的合成

以醋酸酐为溶剂, 将9, 9-二(4-羟基苯基)呫吨与浓硝酸在15 ℃左右发生硝化反应1.5 h, 形成中间体-9, 9-二(3-硝基-4-羟基苯基)呫吨, 产率为88.5%;继而以Pd/C 为催化剂, 80%的水合肼为还原剂, 在乙醇和1, 4-二氧六环混合溶剂中, 于70 ℃将中间体进行还原反应10 h, 得到目标产物9, 9-二(3-氨基-4-羟基苯基)呫吨, 产率为90.8%, 两步反应总收率为80.4%。 中间体与目标化合物经NMR、FTIR和元素分析等确定了它们的结构。     

Synthesis of 14-aryl or alkyl- 14H-dibenzo[a,j]xanthenes promoted by Mg(HSO4)2

14-Aryl or alkyl-14H-dibenzo[a,j]xanthenes were prepared by condensation of 2-naphthol and aldehydes in the presence of Mg（HSO₄）₂ as an efficient,cheap,readily available and eco-friendly catalyst.This procedure has the advantages of high yields,easy work-up,short reaction times,and green conditions.     

Incorporation of spiroxanthene units in blue-emitting oligophenylene frameworks: a new molecular design for OLED applications

We report herein the incorporation of xanthenyl units into two extended π-conjugated phenylene systems, namely indenofluorene and pentaphenylene. Thus, dispiroxanthene-indenofluorene (DSX-IF) and dispiroxanthene-ladderpentaphenylene (DSX-LPP) have been designed and synthesized through short and efficient synthetic approaches. These two molecules possess a 3π-2-spiro architecture (3π-systems/2-spiro bridges), in which two xanthenyl cores are spirolinked to a π-conjugated backbone either indenofluorene for DSX-IF or pentaphenylene for DSX-LPP. The structural, electrochemical, and photophysical properties of these blue/violet emitters have been studied in detail and compared to those of their 'all carbon' analogues with spirofluorenyl cores instead of spiroxanthenyl cores, namely dispirofluorene-indenofluorene (DSF-IF) and dispirofluorene-ladderpentaphenylene (DSF-LPP), previously reported in the literature. Finally, the application of DSX-IF and DSX-LPP as new light-emitting materials in nondoped organic light emitting diodes is reported. A detailed optical study of the different electroluminescence spectra is notably presented, with an emphasis 1) on the origin of the low-energy emission band observed in the case of DSX-LPP and 2) on the unexpected optical contribution of the well-known hole-transporting-layer NPB (N,N'-di(naphtyl)-N,N'-diphenyl(1,1'-biphenyl)-4,4'-diamine).