Synthesis of Pyridylazo-substituted Chromogenic Calix[4]arenes

Calixarenes are a versatile class of macrocyclic compounds which have attracted extensive interest due to their ability to form host-guest complexes and act as enzyme mimic, especially when appropriately functionalized1. Introduction of azo group to calixarenes can make the later to be easily detected in the process of molecular recognition, azo groups have been introduced into calixarenes by the diazo-coupling reaction of calix[4]arene with BF4- or chloride salt of substituted benzene diazon…     

Synthesis of （p-Formylphenyl）azo Calix[4]arenes

Five novel azo calix[4]arenes were reported. The p-aminobenzaldehyde was diazotized with sodium nitrite in aqueous hydrochloride solution. Mono-, bis-, tris- and tetrakis(p-formylphenyl)azo calix[4]arenes (including proximal and distal isomers) were obtained respectively by diazo-coupling in different molar ratio to calix[4]arene(1) under pH=7.5--8.5 at 0-5℃. All (p-formylphenyl)azo calix[4]arenes were characterized by ^1H NMR, ^13C NMR, IR, MS (ESIMS) spectroscopies and elemental analysis.     

新型偶氮杯[4]芳烃的合成与构象研究

使用相应的w-硫醚羧酸酰氯与杯[4]芳烃或者偶氮杯[4]芳烃酰化合成了一类新型的杯[4]芳烃衍生物。分离得到六个新化合物4a-4c和5a-5c，并使用MALDI, EA, ¹H和¹³C NMR进行了表征。NMR图谱表明偶氮杯[4]芳烃衍生物 5a-5c均为1,3-转换构型，而4a-4c则均为锥式构型。对偶氮杯[4]芳烃衍生物5a-5c的红外和紫外性质也进行了研究。     

New Tetrafunctionalized Cone Calix[4]arenes as Neutral Hosts for Anion Recognition

Abstract

The synthesis and anion binding properties of several new cone calix[4]arenes having different flexibility and tetrafunctionalized at the upper rim with various type of hydrogen bonding donor groups such as thioureas (1–3), trifluoroacetamides (4, 5) and perfluorinated alcohols (6) are reported. The results obtained show that thiourea receptors are the most effective in the complexation of all anions and that the rigid cone compound 2 is more efficient than the mobile cone analog 1 in the binding of spherical anions, whereas the reverse is true for the complexation of tetrahedral H₂PO₄ ^? anion.     

Synthesis of p-Formylphenylazo Calix [ 4 ]arenes

Calixarenes are a versatile class of macrocyclic compounds, which have attracted extensive interest due to their ability to form host-guest complexes and act as enzyme mimic. Moreover, a number of calixarenes with D-π-A units have been synthesized, and their second-order nonlinear optical (NLO) properties investigated.     

Synthesis of （p—Substituted phenyl）azo Calix[4] arenes

A novel method for the preparation of chromogenic calixarenes with azo groups was reported.p-Substituted(-NO2,-CH3,-Cl)amilines were diazotized with isoamyl nitrite in EtONa/EtOH under refluxing condition.Fifteen mono-,bis-,tris-and tetrakis(p-substituted phenyl)azo calix[4]arenes (including proximal and distal isomers) were obtainged respectively by diazo-coupling in different molar ratio to calix[4]arenes(1) under pH=7.5-9.0 in non-aqueous solution at 0-5℃.^1H NMR and ^13C NMR spectra of (p-substtituted phenyl)azo calix[4]-arenes indicated that they existed in cone conformation in solution.     

Synthesis and Properties of Upper Rim Schiff Base Calix[4]arenes

The synthesis and properties of upperrim Schiff base calix[4]arenes are described in thisarticle. Tetrakis-p-bromomethylcalix[4]arene(1) reacts with hexamethylenetetramine to givetetrakis-p-formylcalix[4]arene (2) in highyield. Then upper rim Schiff base calix[4]arenes 3 can be easily synthesized by 2 reacting withappropriate alkylamines. The complexation ability of3 toward transition metals Pb²⁺, Cu²⁺and Co²⁺ was studied by UV-VIS spectrophotometry.     

Synthesis and Fluorescence Sensing Properties of Calix[4]arenes Containing Fluorophores

New fluoroionophores 4 and 5 derived from calix[4]arene triester monoacid chloride with 2-amino-4-(1,3-benzothiazol-2-yl)phenol and 4-aminoquinaldine, respectively, have been synthesized. A preliminary test showed that the fluorescence intensity of 5 was very low, so only 4 was subjected to cation recognition investigation. In methanol, the fluorescence intensity of 4 was quenched by Na⁺. The fluorescence intensity decreased linearly with increasing Na⁺ concentration with a stability constant of log K = 2.91 ± 0.08. No significant response was observed for other alkali metal ions under the same experimental conditions.     

新型生色杯[4]芳烃衍生物的合成及其对CU2+的识别

设计并合成了含偶氮基、酰胺基和席夫碱基的新型生色杯[4]芳烃衍生物(1),其结构经1H NMR,IR,MS和元素分析表征.荧光光谱研究表明,1在λex/λem=370 nm/422 nm处有最大峰;1与Cu2+配合时荧光显著猝灭.     

Synthesis of New Calix[4]arenes Functionalizated by Acetylhydrazide Groups

A series of new calix[4]phenols, calix[4]resorcinols and calix[4]pyrogallols with acetylhydrazide substitutes has been␣synthesized with high yields by hydrazinolysis of ester group containing calix[4]arenes. The synthesized calix[4]phenols adopt the cone conformation while the calix[4]resorcinol and calix[4]pyrogallol derivatives prefer the boat conformation. The amide fragment of the hydrazide groups predominantly exists in the trans-conformation. The binding ability of synthesized calix[4]arenes toward transition and alkali metals by solvent extraction has been investigated.     

Synthesis of Calix[4]pyrroles: A Class of New Molecular Receptor

RecentlySesslerandco-workersdiscoveredthatthemeso-octaalkylporphyrinogensshowedinterestinganionandneutralsubstratebindingpropertiesandmightserveasaclassofneweasy-to-makemolecularreceptorintheareaofsupramolecularchemistry'.However,themeso-octaalkylpor...     

Ultramacrocycle with Four Calix[4]arenes: Synthesis and X-Ray Crystal Structure of A Quadruple Calix[4]arene

A quadruple calix[4]arene has been synthesized efficiently from the known diaminocalix[4]arene and 4,4′-biphenyldisulfonyl chloride in just one step (38% yield). The compound has been fully characterized including the determination of the X-ray crystal structure.     

Synthesis and Extractive Properties of Hexaphosphorylated Calix[6]arenes

A series of calix[6]arenes substituted with phosphoryl functional groups were prepared by the Arbuzov reaction of hexakis(chloromethyl)calix[6]arene hexamethyl ether with isopropyl esters of trivalent phosphorus acids, followed by appropriate chemical transformations. Molecular modeling and NMR data show that phosphorylated calix[6]arenes exist in the stereochemically labile 1,2-alternate conformation. The extractive power of these compounds with respect to americium and europium was studied. Due to the cooperative binding of the metal cation with phosphoryl groups, the phosphorylated calixarenes are more effective extractants than their acylcic analogs and commercial organophosphorus extractants.     

Multichromophoric Calix[4]arenes: Effect of Interchromophore Distances on Linear and Nonlinear Optical Properties

Multichromophoric calix[4]arenes with two or four disperse red one (DR1) moieties linked to the lower rim have been synthesized. The second‐order nonlinear optical activity was measured by using the electric‐field‐induced second‐harmonic generation technique and there was a nearly linear increase of the μβ value with the number of chromophores in the molecule without affecting the charge‐transfer absorption wavelength. The effect that the number of DR1 units plays on the hyperpolarizability, the dipole moment, and the absorption maxima has been also studied by using quantum chemical calculations. It was found that it was necessary to synthesize multichromophores with distant chromophores to obtain large nonlinear optical responses.     

Novel Disubstituted Calix[4]arenes Containing Chromogenic Groups on the Lower Rim: Synthesis,Structural Identification,and Absorption Properties

5,11,17,23‐Tetra‐tert‐butyl‐25,26,27,28‐tetrahydroxycalix[4]arene and 25,26,27,28‐tetrahydroxycalix[4]arene were synthesized based on previous literature. Firstly, several azo dyes were synthesized, and then, these dyestuffs were chlorinated through reaction with thionyl chloride. Secondly, the azo compounds bonded with methylene chloride and reacted with 25,26,27,28‐tetrahydroxycalix[4]arene, and then, six novel disazocalix[4]arene derivatives 4 ( a – f ) were achieved. Their structures were characterized as Fourier transform infrared, ¹H‐NMR, and elemental analysis. In this study, we investigated the solvatochromic properties of the compounds and the acid–base effect on their ultraviolet–visible absorption by using six solvents.     

A New Chromogenic Diester-calix[4]crown Receptor for Ca~(2 )

MolecuIardesignofchromogeniccalixarenederivativeshasattractedmuchattentioninthepastyears,fortheirpotentialapplicationsinopticalsensors'.Asoneofthemostimportantexamplesofchromogeniccalixarene,calixarenederivatives',especiallycalixcrowns3bearingazophenolmoietyhaveexhibitedconsiderablechangesintheirabsorPtionspectrainthepresenceofalkalicationsororganicamines'.Alkalineearthcations,especiallyCa' hasabiologicallyimportantrole,butfewstudiesonchromogeniccalixarene-basedreceptorforCa2 havebeenmade5.H…     

多重氮杂杯[4]芳烃和双杯[4]芳烃的合成与阳离子萃取性能

多重氮杂杯[4]芳烃和双杯[4]芳烃的合成与阳离子萃取性能;杯[4]芳烃;双杯[4]芳烃;多重氮杂;萃取     

Crystallographic and Inclusion Properties of some Diacetylated Calix[4]arenes

Three 5,17-diacetylcalix[4]arene derivatives 3–5 have been prepared, evaluated for inclusion properties, and their single crystal X-ray structures determined. The diacetyl calixarenes 3 and 4 were obtained by acetylation of their parent dimethoxy 1 or dipropoxy 2 compounds, respectively, whereas 5,17-diacetyl-25,26,27,28-tetrapropoxycalix[4]arene 5 was prepared by alkylation of 4. Crystallisation of 3 resulted in no inclusion from chloroform, but yielded lattice inclusion compounds from acetonitrile or acetone. The calixarene 3 maintains its cone conformation in these crystals, but displays degrees of distortion depending upon the included solvent. Crystal structures of solvent-free 4 and 5 are also described. A new preparation of the monomethoxy derivative 6 is described, and its X-ray structure with chloroform guest is analysed.     

Synthesis and Anion Recognition of A Novel Tetraamides Calix [4 ] (aza) crown

Anion recognitions have attracted considerable attention in supramolecular chemistry because of its possible ap plication in the field of biology and environment. [1] In recent years, considerable efforts have been devoted to the development of anion fluorescent and colorimetric sensors. [2]