Calix[4]quinones. Part 4: The ClO2 oxidation of calix[4]arene dialkyl ethers

Except for the special case of calix[4]arene diethyl ether 1, the chlorine dioxide oxidation of dialkyl ethers 2-5 yielded only the corresponding calix[4]diquinone dialkyl ethers 8-11. Chlorine dioxide oxidation of calix[4]arene diethyl ether 1 produced two isomeric products 6 and 7, which were stable enough to be isolated by column chromatography. However, a slow conformational interconversion between isomeric pair 6 and 7 was observed at room temperature, and the equilibrium was reached after 400 h at 18 °C with an amount of 5:3 in favor of syn-isomer.     

Calix[4]quinones III: The Synthesis of p‐Hydroxycalix[4]arenes by Wolff‐Kishner Reduction

The Wolff‐Kishner reduction of the half‐protected ketal calix[4]monoquinone 3 and its basic hydrolysis product 4 produced a partially reducing product 5 . When the same reduction conditions were applied to the calix[4]quinone benzoates 1 and 2 , the corresponding title compounds, p‐hydroxycalix[4]arenes ( 6 and 7 ), were afforded in one step.     

Synthesis and Characterization of Picolinamide Calix[6]arenes Derivatives

It is well known that calixarenes are extremely versatile classes of macrocyclic receptor able to complex various metal ions as well as to selectively recognize both neutral and charged inorganic or organic species in solution. It is unable to get a clear…     

Synthesis of Calix[4]resorcinarene Amide Derivatives

Three different synthetic routes were developed to introduce carbamoyloxy functional groups at the upper periphery of two calix[4]resorcinarenes. By treating activated esters 2a-b with excess corresponding amine such as 3-(dimethylamino)propylamine 3, ct-phenethylamine 4 and triethylenetetramine 5, six amide derivatives 6a-8b were obtained in high yield (Route 1). The pyridine-linked amide derivatives 9a-b were prepared by using acid chloride intermediate (Route 2).The amide derivatives 10a-b were obtained in moderate yields by direct alkylation of phenolic hydroxyl groups of la-b with N,N-dipropylchloroacetoamide in the presence of K2CO3/KI in acetone (Route 3).     

Synthesis and Absorption Properties of Calix[6]amides—based Polymers

Reacting calix[6]arene hexaesters with poly(ethyleneimine),a series of calix[6]amidesbased polymers were obtained for the first time.It is found that they show high absorption capacities towards soft cations comparing to hard cations,and the absorption abilities enhanced with the increasing of calixarene content,which may indicates the cavity of calixarene plays crucial role in absorption.Polymer 2c shows good selective absorption capability towards Ag^ among the tested cations.     

Synthesis of Calix[4]resorcinarene Schiff Bases

Introduction Calix[4]resorcinarenes are cyclic tetramers in which four resorcinol units are linked via alkylmethylene bridges in the o-position to each resorcinic hydroxyl group[1]. Their structures resemble that of p-butylcalix[n]arenes and render them of interest as host compounds in many contemporary fields of supramolecular chemistry.     

Stereoselective Synthesis and Structure of New Types of Calix[4]resorcinarenes. Complexation of Tetrakis(O,O‐Phosphorus)Bridged‐Calix[4]resorcinarenes with Heavy Metal Atoms

The acid‐catalyzed (with HCl) condensation reactions of resorcinol ( 1 ) with 1‐naphthaldehyde ( 2 ) and isobutyraldehyde ( 3 ) furnished the tetrameric macrocyclic compounds 4 and 6 . Detailed NMR‐investigations of the acetylated tetrameric species 5 surprisingly support a structure not in agreement with the expected all‐cis conformation. The chair conformation (C_2h symmetry) of the acetylated derivative 5 was established through a crystal X‐ray diffraction study. The naphthyl substituents are arranged in trans position above and below the plane made up by the resorcinol units. The reaction of resorcinol 1 with isobutyraldehyde, in accord with expectation, led to the calix[4]resorcinaren ( 6 ). The ¹H NMR spectra of compound 6 and 7 appeared at room temperature as broad signals, indicating a conformation of C_2v symmetry. The reaction of the C‐methyl‐tetrakis‐P‐(chlorodioxaphosphocin)‐calix[4]resorcinarenes ( 8 ) and ( 10 ) with suitable N‐trimethylsilyl organic amines were conducted in tetrahydrofuran suspension, furnishing the P–N‐substituted calix[4]resorcinarenes ( 9 ) and ( 11 ). While in the complexation of C‐methyl‐tetrabromotetrakis‐P‐(dimethylaminodioxaphosphocin)‐calix[4]resorcinarene ( 13 ) with (tht)AuCl (tht = tetrahydrothiophene) the expected, neutral tetra‐substituted complex 15 was formed, the reaction of 13 with moist acetonitrile led to the anionic atomic framework 14 . X‐ray structure determinations of the complexes 14 and 15 show that both possess the cone conformation. In the gold complex 15 , the Au–Cl groups form a loose aggregate, with three Au…Cl contacts of 316–340 pm; one of the groups points towards the centre of the cone. The copper(I) complex 14 displays crystallographic mirror symmetry, with a central Cu₄Cl₅ unit involving tetrahedrally coordinated copper.     

N-硫脲基套索杯[4]冠醚与四硫脲基杯[4]芳烃的合成

控制反应物的物质的量比, 杯式对叔丁基杯[4]-1,3-二乙酸乙酯衍生物1与5或50倍二乙烯三胺反应, 分别得到杯[4]氮杂冠醚2和开链的氮杂杯[4]芳烃衍生物3. 化合物2和3进一步与异硫氰酸苯酯反应得到首例侧链含硫脲基的套索杯[4]氮杂冠醚4和含4个硫脲基的杯[4]芳烃衍生物5, 产率为92%和87%. 新化合物的结构与构象经元素分析、红外、质谱、核磁共振谱等表征证实.     

Synthesis of Flavin–Calix[4]arene Conjugate Derivatives

The synthesis of two new flavin substituted calix[4]arene derivatives, 9 and 10 , is described. The first flavin substituted calix[4]arene derivative 9 was synthesized by the reaction of 3‐methylalloxazine ( 5 ) with 25,27‐bis(3‐bromopropoxy)‐26,28‐dihydroxy‐5,11,17,23‐tetra(tert‐butyl)calix[4]arene ( 4 ) in high yield (92%). The other derivative 10 was prepared from 3‐methylalloxazine‐1‐acetic acid ( 7 ) and 25,27‐bis(3‐cyanopropoxy)calix[4]arene ( 3 ). All new compounds were characterized by a combination of FT‐IR and ¹H‐NMR spectroscopy, and elemental‐analysis techniques.     

Regioselective Bridging Calix[6]arenes: Synthesis and X-ray Structure of Trisbridged Calix[6]arene

The preparation and characterization of gold nanoparticles (～6 nm in diameter) modified with mono-6-thio-β-cyclodextrin (II) is described. The resulting monolayer-protected gold nanoparticles are water-soluble and more stable. The concentration of II plays a crucial role for the distribution of the modified nanoparticles. When the ratio of concentration of II to HAuCl₄,[II]/[HAuCl₄] ≥ 0.93, a stable gold nanoparticle with uniform distribution and diameter of 6.0 ± 0.9 nm will be obtained. The recognition of modified gold nanoparticles to organic guest molecule is researched. The modified gold nanoparticles can make the electrochemical reduction current of nitrobenzene decrease and can be self-assembled in three-dimensional to form spherical clusters with ligand of methylene green.     

杯[4]芳烃衍生物的合成和构象研究

以对取代酚亚甲基桥三聚体和２，６－二溴甲基对取代酚为原料，在ＴｉＣｌ４催化下环化得到６种新的含不同取代基［Ｃｌ，Ｂｒ，ＣＨ３，Ｃ（ＣＨ３）３］的杯［４］芳烃衍生物，核磁共振谱研究表明：它们在溶液中的优势构象为锥形构象。     

Calix[n]arenes as Synthetic Membrane Transporters: A Minireview

Several potential applications of functionalized calix[n]arenes as carriers in transport through membranes of various biological compounds aiming their separation are reviewed. Specific aspects of membrane transport and the use of calix[n]arenes for building synthetic ion channels are discussed.     

Chlorination of Calix[4]arene Derivatives

New convenient method for synthesis of p-chlorinated calix[4]arenes is reported. The sulfuryl chloride was used for chlorination of unsubstituted at the lower rim calix[4]arenes. The products of this reaction were very suitable for further O-alkylation.     

Mono Halogen Substituted Calix[4]pyrroles: Fine-tuning the Anion Binding Properties of Calix[4]pyrrole

Abstract

Single halogen atom (i. e. I, Br, Cl and F) substituted calix[4]pyrroles, compounds 2, 3, 4 and 5, were synthesized. Studies of these systems reveal that replacement of a single β-pyrrolic hydrogen atom can increase the anion binding ability of calix[4]pyrroles for a variety of anions (e. g. Cl^?, Br^?, H₂PO₄ ^? and HSO^? ₄) relative to normal non-halogen substituted calix[4]pyrrole 1. In the case of chloride anion, the expected relative affinity sequence of 5 > 4 > 3 > 2 was observed. This was not found to be true for Br^?, H²PO^? ₄, and HSO^? ₄. Here, the chlorine substituted calix[4]pyrrole 4 was found to display a slightly higher affinity in the case of each anion than the fluorine-bearing derivative 5. This was rationalized in terms of intermolecular NH … F hydrogen bonding interactions being present in CD₂Cl₂ solutions of 5. Support for this latter conclusion came from concentration and temperature-dependent NMR spectroscopic studies.

A matched set of mono halogen substituted calix[4]pyrroles was used to study in detail, the extent to which halogen substituents may be used to fine-tune the anion binding properties of calix[4]pyrroles.     

Synthesis and self-assembly of novel calix[4]arenocrowns: formation of calix[4]areno[2]catenanes

A series of novel calix[4]arenocrowns 1a-c were efficiently synthesized by a one-pot reaction of calix[4]monohydroquinone diacetate 5 with ditosylate 6 and its analogues in the presence of sodium hydroxide. It was found that the calix[4]arenocrowns could form stable pseudorotaxane-type complexes 2a-c with paraquat, and further self-assemble into calix[4]areno[2]catenanes 3a-c with dicationic salt 8 and p-bis(bromomethyl)benzene.     

丙醛间苯二酚杯[4]芳烃烷基化衍生物的合成

以间苯二酚和丙醛为原料合成了丙醛杯[4]芳烃(1),1经不同的烷基化反应合成了新的丙醛杯[4]芳烃烷基化衍生物,其结构经1H NMR和IR表征。     

Darstellung und Struktur neuer Calix[4]aren-Titan(IV)-Imidokomplexe

Synthesis and Structure of New Calix[4]arene Titanium(IV) Imido Complexes The syntheses of the novel calix[4]arene titanium imido compounds [Cax(OMe)₂O₂Ti(NR)] ( 2 ) (R = tBu) and ( 3 ) (R = Mes = 2,4,6-trimethylphenyl) (Cax = C₄₄H₅₂) starting from [Cax(OMe)₂O₂TiCl₂] ( 1 ) and lithium amides LiNHR are described. Complexes 2 and 3 are mononuclear compounds in solution. An X-ray crystal structure analysis of the toluene adduct of 3 (Space group: P 1, lattice dimensions: a = 12.979(2) Å, b = 13.707(2) Å, c = 16.573(3) Å, α = 81.751(11)°, β = 80.555(13)°, γ = 73.541(12)°) reveals that this compound is mononuclear in the solid state. The central atom in 3 is distorted trigonal bipyramidal ligated by two ether oxygen atoms in axial positions, two phenoxide oxygen atoms in the equatorial plane, and an imido nitrogen atom in an equatorial position. The titanium nitrogen bond distance in 3 is 171.8(3) pm.     

无溶剂法合成4,6,10,12,16,18,22,24-八羟基-2,8,14,20-四-{(联三-(3-苯基-2,4,8,10-四氧杂螺[5.5]十一烷基))-(4-(2-(4,6,10,12,16,18,22,24-八羟基)杯芳基)苯基)}杯芳烃螺环树形大分子化合物

以对苯二甲醛、丙二腈为原料, 合成对苯二甲醛单缩醛, 再与季戊四醇反应得到了2,4,8,10-四氧杂-2,9-二(4-二氰基乙烯基苯基)螺[5.5]十一烷, 经水解, 与丙二腈反应, 制备了中间体2,4,8,10-四氧杂-2-(4-二氰基乙烯基苯基)-9-(4-甲酰基苯基)螺[5.5]十一烷(3). 用乙酸酐保护的对苯二甲醛单缩醛与间苯二酚反应, 制备了杯芳烯中间体(6). 将化合物6与过量的化合物3反应, 得到中间体7, 经水解后与过量的化合物6反应, 得到了4,6,10,12,16,18,22,24-八羟基-2,8,14,20-四-{(联三-(3-苯基-2,4,8,10-四氧杂螺[5.5]十一烷基))-(4-(2-(4,6,10,12,16,18,22,24-八羟基)杯芳基)苯基)}杯芳烃螺环树形大分子化合物(9). 总收率为12.7%. 产物结构用IR, 1H NMR, 13C NMR, MS 和元素分析进行了表征, 对影响反应的因素进行了讨论.     

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.