Phosphorotropic Isomerization of Diphosphoryl Calix[4]Arenes in Synthesis of Their Chiral Derivatives

Abstract

Calixarenes are synthetic macrocycles obtainable by joining phenolic units through methylene bridges. Since they have original molecular architecture, they are considered to be important starting materials in design novel host-molecules for molecular recognition and separation. Introduction of chirality into calixarenes seems to be of great value for development of new class of artificial enzymes. Chira1 lower rim trisubstituted calix[4]arenes 2 possessing no plane of symmetry were synthesized with good yields by one-pot procedure consisted in successive treatment of 1,3-di-phosphorylcalix[4]arenes 1 in cone conformation with 1 eq. NaH and benzoyl chloride or methyl monobromoacetate.     

四对-乙酰胺苯磺酰氧基杯[4]芳烃的合成

以对叔丁基苯酚为起始原料,通过缩合、取代反应合成了25,26,27,28-四对-乙酰胺苯磺酰氧基对叔丁基杯[4]芳烃,其结构经FT—IR,^1H NMR和FAB-MS表征。     

新型杯[4]芳烃衍生物的合成

以对叔丁基杯[4]芳烃为起始原料,通过一步或两步取代反应合成了对叔丁基杯[4]芳烃的衍生物(1和2),其结构经FT-IR,^1H NMR,FAB-MS表征．     

Synthesis of New Rigid Dimeric Calix[4]arene

A new Dimeric calixarene from the head to head linkage of two calix[4]arene units fixed in the cone conformation was synthesized via Sonogashira cross-coupling reaction. The structure of 10 was confirmed by NMR, MS and IR-spectroscopy.     

Chiral Calix[3]pyrrole Derivatives: Synthesis,Racemization Kinetics,and Ring Expansion to Calix[9]- and Calix[12]pyrrole Analogues

Chiral pyrrolic macrocycles continue to attract interest. However, their molecular design remains challenging. Here, we report a calixpyrrole-based chiral macrocyclic system, calix[1]furan[1]pyrrole[1]thiophene ( 1 ), synthesized from an oligoketone. Macrocycle 1 adopts a partial cone conformation in the solid state, and undergoes racemization via ring inversion. Molecular dynamics simulations revealed that inversion of the thiophene is the rate determining step. Pyrrole N-methylation suppressed racemization and permitted chiral resolution. Enantioselective N-methylation also occurred in the presence of a chiral ammonium salt, although the stereoselectivity is modest. A unique feature of 1 is that it acts as a useful synthetic precursor to yield several calix[n]furan[n]pyrrole[n]thiophene products (n=2–4), including a calix[12]pyrrole analogue that to our knowledge constitutes the largest calix[n]pyrrole-like species to be structurally characterized.     

Extraction of Americium with Substituted Calix[4]Arenes from Alkaline Solutions

Extraction of ²⁴¹Am and ¹⁵²Eu from carbonate-alkaline medias with solutions of functionalized calix[4]arenes and their nonmacrocyclic analogs in m-nitrobenzotrifluoride was studied. The dependencies of the Am distribution ratios on pH of the aqueous phase in the range 10 -13.5 and on the position and nature of functional groups in the calixarene core were examined. The composition of extractable solvates of americium with functionalized calix[4]arenes was determined. Thiacalixarenes extract americium more efficiently from alkaline solutions, as compared to calixarenes, demonstrating higher Am/Eu separation factor. Functionalization of the calixarenes improves the Am extraction efficiency and Am/Eu separation factor as well. In the case of thiacalixarenes, functionalization considerably decreases the extraction efficiency and selectivity.     

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。     

一种新型含喹啉环杯[4]芳烃衍生物的合成

以对叔丁基苯酚为起始原料,把酯基和具有荧光性质的喹啉环引入杯芳烃大环分子中,通过缩合,两步取代反应,获得了具有荧光性质的新型含喹啉环杯[4]芳烃衍生物。其结构经1H NMR,IR,MS和元素分析表征。     

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 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.     

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 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.     

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 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).     

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。     

四硫脲基杯[4]芳烃衍生物的合成

对叔丁基杯[4]-1,3-二乙酸乙酯与过量的二乙基三胺反应,生成含有游离氨基的杯芳烃酰胺衍物(2),2再与异硫氰酸苯酯反应合成了含4个硫脲基的杯[4]芳烃衍生物,其结构经1H NMR,IR,MS和元素分析表征。     

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

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

Syntheses of Lower-Rim-1,3-Crowned Calix[6]Arenes and their Complexation Abilities Toward Cations

An approach to lower-rim-1,3-crowned calix[6]arene and its derivatives in one-pot process has been accomplished. In the presence of very excess Na2C03 (27-150 equivalent per mole p-tert-butyleal ix[6]arene 1) in acetonitrile, the lower-rim-1,3-bridged calix[6]crown-3 (4), the bistosylethoxy-ethyl derivative of 4 (5), as well as the intermediate of 4, monotosylethoxyethyl p-tert-butylcalix[6]arene 3, were obtained in rational yields, the distribution of the three compounds varied with the amount of the base used and other selected experimental conditions. 4 exhibits high selectivity towards Li⁺. 3 may be the first example of ionophore with high Et2NH2⁺ selectivity.     

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.     

Calix[4]arenequinazolinones. Synthesis and structure

The synthesis of calix[4]arenes bearing two quinazolin-4-ones group at the upper rim is decribed. ¹H NMR spectra and quantum chemical calculations make it possible to suggest that calix[4]arenequinazolinones form three rotamers in solutions at room temperature, due to the restricted rotation of the quinazolinone fragments. The X-ray structure investigation indicates that quinazolin-4-onecalix[4]arene exists in the crystal state as the methanol 1:1 inclusion complex.