Synthesis of 1-(4-Antipyrinyl)-3-(3-Chlorophenyl)-Triazene and Its Colour Reaction with Mercury

TheantiPyrinldiazoaminoreagentsweresensitivefOrCd(II)andHg(II)11-3l-Receatly,anewreagrntlK4-antiPyrinl)-3<3-Chlorophenylytrime(APPT)wasSynthsized.ThecolourreahonofAnCPTwithmerCurywasstUdied-ThemethodfordeterminingmicroaznountofmempwithAPCPTwasmoresensitiveandhighlyselective.AnditwasusedtodeterIninemercmpcoboinnatUralwaterwithsatisfactryresults.ExperimeutalAPP~:Model75lspectrophotOmeter,ModelpH-2meter(madeinShanghai).Sbodard~solution:DissolveHgCl2(A.R.)inWate.AddseveraldroPso…     

Adsorptive Stripping Voltammetric Study of the Enhancement of Copper(Ⅱ) in Phosphate and Carbonate media and in the Presence of Silicate

1.InteductionAdsorPtivestriPPingvoltanUnetry(AdSV)isasensitivendhandyel~talalldevelopeinrecentyears[ll.~,mOStarheS~oneboo~candmetal-owicligandco~,whichcanbeadsoboonthesurfaCeOfeledreadilI21,e.g.2deldebontofCU(II)wasbbtalnedwithitsdi~lglyositall3a].Thedsrptwbooftwleino~cco~OfIDetalshavseldOmareedattentionWAn~tomp'thereareoulytwoinowiccompounwhichhavbenmprtedtohavthepowerOfadsorption(sulfide[4])oradsorptiveeIthanCemen(dspe,5hmesI3b,5l).AlthoUghhigherenhance-mentscanbereachedwhenhCxam…     

Reaction of Phenylethyne with 2,4-Pentanedione in the Presence of Manganese(Ⅲ) Acetate and Oxygen

WerecentlyrePOrtedmanganese(III)acetate-mediatedoxidatheftee-ndtalCycliZaionofalkeneswith1,3-diones[l-3],o-ketoeSters[4,51andaretoacetamjdesI6]inthepresenceofmolecularoxygenthatyteldedl,2-dioxan-3-olsingoodytelds.Asindlarreachonwasinveedgaedonalkynes,whichgaverisetonovelheterOCyliccomPOundsHereinwedescribetheresu1tS(Schemel)WhenthereachonofDhenVethVne(l)with2,4-pentanedione(2)wncAnedoutinthepresenceacetyl-2-methyl-5-phenylfuran(5)(Tablel,entryl),ThestructUralassigIUnentSarebasedonthe…     

A Novel Fluorescent Aminoacid Designed for Fluorometric Detection of Cu(II)

IntroductionIthasbeenwellknownthatα aminoacidcouldeffi cientlychelateCu(II) .1 3Applicationsbasedonthisnovelbindingcharacterhavebeenreported ,forinstance ,thechiraldiscriminationofD andL aminoacidsinaCu(II) cyclodextrincomplex4 ,5andtherecoveryofpyrenefluores cencebyaminoacidfromapyrene Cu (II) cyclodextrincomposite .6 ItwasthusenvisagedthatarationaldesignwouldleadtoanaminoacidderivativethatcouldworkasanovelligandforefficientdetectionofCu(II) .Acombina tionoftheaminoacidwithafluoropho…     

Synthesis of N-(4-Salicylideneiminoaryl)monoaza Crown Ethers and Dioxygen Affinities of Their Cobalt(II) Complexes

IntroductionSchiffbasesandtheirmetalcomplexeshavebeenap pliedwidelyinthefieldofcatalyticchemistry ,liquidcrystalsandphotochromism .1 3ManySchiffbaseligandscontainingcrownetherpossessdifferentrecognitionsitesforbothalkaliandtransitionmetalguestcations,4 forexample ,theNa(I)orK(I) /Co(II)hetero nuclearcomplexesofcrownedSchiffbasecanbindoxygenmolecule (O2 )toformstablesoliddioxygenadducts .5 7Gebbinkandco workershavereportedaK(I) /Cu(II)sandwichcomplexwhichcanacceleratethefor mationofdioxyg…     

Detection of NO2 Based on 4-Carboxyl-4'-hydroxy Azobenzene and Its Cu(Ⅱ) Complex

<正>An organic ligand and its Cu(II) complex formulated as (C_(13)H_(10)N_2O_3)·5H_2O (H_2L·5H_2O, 1) and Cu(HL)_2(phen)·0.125H_2O (2, H2L = 4-carboxyl-4′-hydroxy azobenzene, phen = 1,10-phenanthroline) have been synthesized and structurally characterized by single-crystal X-ray diffraction. In the two compounds, H_2L and HL exhibit a trans-conformation. Complex 2 shows a mononuclear Cu(II) structure with the hydroxyl group of HL uncoordinated. Complex 2 is assembled into a three-dimensional (3D) supramolecular architecture by hydrogen bonds and π-π stacking interactions. H_2L and compound 2 can detect NO_2 via reversible and irreversible color changes, respectively. The mechanism for the color changes is investigated.     

Synthesis and Structure of Tetraploid (Imidazole) Copper(II) Terephthalate,[Cu(Im)_4](teph)

Introduction　　Imidazoleisofconsiderableinterestasaligandwhichpresentsinmanybiologicalsystems (forexampleinthehistidylresidueofproteins)providingapotentialbindingsiteformetalions .Imidazoleasanunidentateligandcanformcomplexeswithmetalionsthroughitstertiarynitro genatom .Somecomplexesofimidazoleanditsderivativeswithtransition metalionshavebeenreported .1 4　　Thepreparationofthecomplexesofcopper(II)car boxylatewithavarietyofbasicligandsandtheirmagneticandspectralpropertieshavebeenreported .5,…     

Synthesis, Characterization and Antimicrobial Activity of Potassium Hydro(benzoyl)(phthalyl)borate and Its Cobalt(II), Nickel(II), and Copper(II) Complexes

A new organoborate ligand, hydro(benzoyl)(phthalyl)borate has been synthesized as its potassium salt (KL) and treatment of KL with one equivalent of MCl2•6H2O gave complexes ML(H2O)x•Cl [x＝2, M＝Co(II), Ni(II); x＝1, M＝Cu(II)]. All compounds were characterized by elemental analysis, FTIR, 1H NMR, ESI MS, UV-Vis techniques, conductivity and magnetic data measurements. Spectroscopic results suggest a square planar geometry in the Cu(II) complex, while the Co(II) and Ni(II) complexes possess an octahedral geometry. Antibacterial activities (in vitro) of the ligand and its metal complexes were studied against two Gram positive (B. subtillis and B. magterium) and two Gram negative bacteria (E. Coli and S. boydi) at a single concentration (75 μg/mL) by using the Disc diffusion method. Antifungal activities (in vitro) were also checked for the compounds by using the same method against Candida albicans 10261, Penicillium sp. and Asperjillius niger., at a single concentration (50 μg/mL). The results showed that all the metal complexes, specially the nickel(II) complex, have higher antibacterial and antifungal activities than the corresponding potassium salt.     

Studies on the Kinetics of the FO CO Reaction

IntroductionAproposedcycleinvolvingtheFOradicalsisl:ThecontributionofthiscycletothecatalyticdestrUctionofozoneisdeterndnedbythefirststep.Thereaction(l)isalsothoughttobeapossiblesinkforatInosphericCO2.Baueretal.3gavearateconstantofl.24.lO-i3cm3/sforreaction(l),whichwasbelievedtobecorrectwithinafactorof2at9(X)-l4(X)K.Theactivationenergywasestimatedtobe46.OkJ/mol.Bedzhanyanetal.4reportedk<4xlO-"and<5xlO-l6cm3/sat3ooand55OK,respectively.Alowerbarrierofl3.8kJ/molcanbeextrapoIated.Francisco…     

Preparation,Crystal Structure and Properties of a Pentametallic 3-Ferrocenyl-2-crotonic acid-Bridged Copper(II) Complex

IntroductionDimericcopper(II)carboxylatescontainingavarietyofoxygenandnitrogen donorligandshavebeenextensivelyinvestigatedandtheirpreparations ,magneticandspectralpropertieshavebeenreviewed .1 5Differentkindsofcopper(II)carboxylateadductshavebeensynthesizedandalsodinuclearcopper(II)complexeshavebeenearlystud iedasusefulmodelstoestablishmagneto structuralcorre lationsforspinexchangebetweenmetalions .Inparticu lar,theoccurrenceofdicopperionsattheactivesiteofthevariousformsoftheoxygencarrierpro…     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.     

Copper-catalyzed multicomponent reactions of 2-iodoanilines,benzylamines, and elemental sulfur toward 2-arylbenzothiazoles

A relatively cheap copper salt-catalyzed, three-component approach providing 2-arylbenzothiazoles in good to excellent yields from readily available 2-iodoanilines, benzylamines, and sulfur powder is reported. This methodology allows preparation of various classes of 2-arylbenzothiazoles and provides a general, reliable approach.