An Unprecedented Photochemical Reaction for Anthracene‐Containing Derivatives

A series of anthracene‐containing derivatives have been synthesised and characterised. The photochemical behaviour of these derivatives have been investigated by ¹H NMR spectroscopy. An unprecedented photolysis reaction for anthracene‐containing derivatives was observed in the case of anthracenes directly armed with a ‐CH₂O‐R group upon UV irradiation. The photolysis reaction process has been demonstrated to occur in three steps. Firstly, the anthracene‐containing derivatives are converted into the corresponding endoperoxide intermediate upon UV irradiation in the presence of air; then, the endoperoxide intermediate is decomposed to the corresponding starting compound and 9‐anthraldehyde; finally, 9‐anthraldehyde is further oxidised to anthraquinone. Additionally, the photolysis reaction of anthracene‐containing derivatives is significantly promoted in the presence of a thiacalix[4]arene platform.     

四（对叔丁基）硫杂杯[4]芳烃选择性包合四氟硼酸分子：晶体结构和理论研究

X－射线晶体衍射测定了4－(对叔丁基)硫杂杯[4]芳烃选择性地包合四氟硼酸分子。晶体学数据为：C₄₀H₄₉O₄S₄BF₄，M_r=808.88， 四方锥， 空间群 P4/nmm，a=1.5887(2), b=1.5887(2), c=0.8428(0) nm, V=2.127(2) nm³, Z=2, D_c=1.263 g·cm^-3, R₁=0.0405, _WR[I>2σ(I)]=0.1218. ¹⁹F NMR谱中，在-151.4 ppm处出现的峰，证实了四氟硼酸的存在。用Bader的分子中的原子理论方法计算了分子结构中的非共价键相互作用。结果显示，在四氟硼酸包合物中，除了F…H－C氢键作用和阳离子－阴离子的静电作用外，F^δ--C^δ+静电作用的存在也对4－(对叔丁基)硫杂杯[4]芳烃憎水空腔包合氟硼酸分子起到了稳定作用。     

Self-assembly of nanosized aggregates based on the photoswitchable <Emphasis Type="Italic">p-tert</Emphasis>-butyl thiacalix[4]arene derivative and Fe <Superscript>III</Superscript>, Cu<Superscript>II</Superscript>, and Ag<Superscript>I</Superscript> cations

New p-tert-butyl thiacalix[4]arene tetrasubstituted at the lower rim and containing the azobenzene fragments in the 1,3-alternate configuration was synthesized. Its receptor properties with respect to d-metal cations (Fe ³⁺, Cu²⁺, Ag⁺) were studied using UV spectroscopy and dynamic light scattering (DLS). The ability of p-tert-butyl thiacalix[4]arene to molecular recognition of silver cations was estimated by UV spectroscopy. The aggregation of these systems was studied by the dynamic light scattering method.     

Synthesis and Inclusion Properties of a Novel Thiacalix[4]arene-Based Hard–Soft Receptor with 1,3-Alternate Conformation

A novel ditopic receptor possessing two complexation sites and bearing 1,3-alternate conformation based on thiacalix[4]arene was prepared. The binding behaviors with alkali metals and silver ion have been examined by ¹H NMR titration experiment. Although the formation of the heterogeneous dinuclear complexes was not observed, the exclusive formation of mononuclear complexes of 1,3-alternate-3 with metal cations is of particular interest in negative allosteric effect in the thiacalix[4]arene family. These findings demonstrate that preorganization, subtle conformational changes and affinity have a pronounced effect on the complexation process between the two different arms placed at the two edges of the thiacalix[4]arene cavity.     

Hard–Soft Receptors, Tetrakis[(N,N-diethylaminocarbonyl)methoxy] thiacalix[4]arene Derivatives with cone and 1,3-alternate Conformation

Direct O-alkylation of p-tert-butyltetrathiacalix[4]arene with N,N-diethylchloroacetamide afforded two conformational isomers (1,3-alternate and cone) of tetrakis[(N,N-diethylaminocarbonyl)methoxy]thiacalix[4]arene and 1,3-disubstituted bis[(N,N-diethylaminocarbonyl)methoxy]thiacalix[4]arene, depending on the base used. The complaxation behaviors of the tetrakis isomers were assessed by ¹H NMR titration experiments. Evidence of 1:2 (homo- and hetero-dinuclear) complexes formation of 1,3-alternate-tetrakis[(N,N-diethylaminocarbonyl)methoxy]thiacalix[4]arene with alkali (K⁺ and Na⁺) or transition (Ag⁺) metal ions was obtained. Interestingly, it was found that the cone-tetrakis[(N,N-diethylaminocarbonyl)methoxy]thiacalix[4]arene required a prior Ag⁺ complexation to form 1:2 heterodinuclear complex. Received in final form: 26 January 2005     

Synthesis and Properties of New Thiacalixarene Derivatives with Palladium Ion

Three new thiacalix[4]arene derivatives, 5,11,17,23-tetra-tert-butyl-25,27-di(2-hydroxyethoxy)-26,28-dihydroxythiacalix-{}[4]arene (2), 5,11,17,23-tetra-tert-25, 26,27,28-tetrakis[(methylcarboxyl)methoxy]thiacalix[4]arene (3),5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis(2-hydroxy-1-propanoxy)thiacalix[4]arene (4), were synthesized for the first time. The coordination properties of thiacalix[4]arene(1) and its derivatives (2 and 4) were investigated by detecting the interactions betweenthese compounds and two palladium complexes, cis-[Pd(en)(H₂O)₂]²⁺ and cis-[Pd(dtco-3-OH)(H₂O)₂]²⁺, by means of electrospray ionization mass spectrometry (ESI-MS) technique.     

一种基于硫杂杯[4]芳烃的高效银离子载体

合成了基于下缘含有酰肼基团的硫杂杯芳烃衍生物的银离子载体1,其核磁研究证实硫杂杯芳烃以1,3-交替构象存在,并且通过非竞争萃取实验和竞争萃取实验研究了它对碱金属和过渡金属离子（Li⁺, Na⁺, K⁺, Cs⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺ and Ag⁺）的键合能力和选择性。实验结果表明：将酰肼基团引入1,3-交替构象的硫杂杯芳烃骨架的下缘可以提高其对Ag⁺的键合能力和选择性,同时,对Cu²⁺的萃取能力较弱,对碱金属离子和其它的重金属离子几乎没有萃取能力。进一步的核磁滴定和电喷雾质谱实验显示化合物1与银离子形成配合物的配合计量比为1：1,由此推断主要由“N-Ag⁺”配位键以及硫杂杯芳烃骨架的协同作用构成了化合物1与银离子的配合模式。     

Synthesis,crystal structure and complexation behaviour of a thiacalix[4]arene bearing 1,2,3-triazole groups

The structure and complexation behaviour of 1,3-alternate-1,2,3-triazole based on thiacalix[4]arene,1,3-alternate-1 and 2 have been determined by means of X-ray analysis, fluorescence and ¹H NMR spectroscopy. The X-ray results suggested that the nitrogen atom N3 on triazole ring can act as hydrogen bond acceptors in the self-assembly of a supramolecular structure. The fluorescence spectra changes indicated that the thiacalix[4]arene bearing 1,2,3-triazole groups were highly selective for Ag⁺ in comparison with other tested metal ions by enhancement of the monomer emission of pyrene. The ¹H NMR results suggested that Ag⁺ can be strongly bonded by the triazole groups with the cooperation of the ionophoric cavity formed by the two inverted benzene rings and the sulfur atoms of the thiacalix[4]arene.     

Aminolysis of p‐tert‐Butyl‐tetrakis[(ethoxycarbonyl)methoxy]thiacalix[4]arene

A convenient method for preparation of thiacalix[4]arene tetraamides in high to good yields by reacting conic or 1,3‐alt‐p‐tert‐butyl‐tetrakis[(ethoxycarbonyl)methoxy]‐thiacalix[4]arene with excess monoamines or diamines is reported. In most cases, corresponding tetraamides with original conformation were obtained. However, when the cone one was reacted with ethylenediamine or propylenediamine, the obtained tetraamides possessed partial conic conformation, which meant that conversion of conformation occurred.     

Sulfur‐linked Phenolates as Ligands for the Syntheses of Low‐Nuclearity Iron(III) Complexes

Exploiting thiacalix 4 arene and sulfur‐bridged bisphenolates as ligands for bioinorganic studies involving iron(III) requires the prior development of synthetic routes (varying substituents and reaction conditions) to construct complexes with low nuclearities and accessible coordination sites, which was in the focus of this investigation. Treating p‐tert‐butylthiacalix 4 arene (H₄TC) and 1, 4‐dimethyl‐p‐tert‐butylthiacalix 4 arene (Me₂H₂TC) with Fe[N(SiMe₃)₂]₃ yielded in the formation of the iron(III) complexes [(Me₃SiTC)₂Fe₂] ( 1 ) and [(Me₂TC)₃Fe₂] ( 3 ), respectively. While 1 is a sandwich compound, in 3 one [Me₂TC]^2– unit is bridging two [Me₂TCFe]⁺ moieties. Employing thiobisphenolates as ligands it turned out, that in dependence on the residues R and the preparation method it is possible to selectively access sandwich, anionic or neutral complexes, which were shown to contain central high‐spin iron(III) atoms. The syntheses, structures, and electronic properties of three iron(III) bisphenolate complexes, [^ClL₂Fe]NEt₃H ( 4 ), [^MeLFeCl₂]NEt₃H ( 5 ), and [^tBuLFeCl(thf)] ( 7 ) are discussed.     

Synthesis and Structure of a 1,3-alternate-Thiacalix[4]arene diamide Derivative

A novel receptor possessing two complexation sites and bearing 1,3-alternate conformation based on thiacalix[4]arene, confirmed by single crystal X-ray analysis, was prepared. The tetrathiacalix[4]arene diamide shows strong intramolecular hydrogen bonding. The binding behavior towards K⁺ and halides has been examined by ¹H NMR titration experiments.     

Molecular Design of Calixarene 5. Syntheses and Cation Selectivities of Novel Schiff's Base p‐tert‐Butylcalix[4]arenes

Five novel Schiff's bases p‐tert‐butylcalix[4]arenes have been synthesized in high yields by the reaction of 1,3‐distally disubstituted p‐tert‐butylcalix[4]arene amine (1) with the corresponding aromatic aldehydes, and their cation binding abilities and selectivities with alkali and heavy metal ions have been evaluated by solvent extraction of aqueous metal picrates to show the highest Ag⁺ extractability for Schiff's base p‐tert‐butylcalix[4]arene (6) and the best Na⁺/Li⁺ and Ag⁺/Ti⁺ selectivities for Schiff's base p‐tert‐butylcalix[4]arene (4 and 2) over any other calix[4]arene derivatives, respectively.     

Comparative study of calix[4]arene derivatives: implications for ligand design

The first comparative theoretical study of three parent calix[4]arene analogues (calix[4]arene, thiacalix[4]arene, and homooxacalix[4]arene) has been performed using molecular dynamic simulations and density functional theory (MPWB1K/6-311G^∗∗//B3LYP/6-311G^∗∗) methods. The theoretical observations herein including optimized geometry, polarity, and atomic charge data provide that homooxacalix[4]arene would offer more efficient platform for metal ion recognition compared to thiacalix[4]arene or calix[4]arene.     

Ionselective electrodes based on adamantylthiacalix[4]arenes for alkali cations determination

The possibility of using three derivatives of p-R-thiacalix[4]arene: tetraethyl ester of p-(1-adamantyl)thiacalix[4]arene acid (I) and asymmetric p-tert-buthylcalix[4]-p-R-thiacalix[4]arene “molecular tubes” [R = tert-Bu(II), 1-adamantyl(III)] as ionophores in PVC-membrane ISEs for the determination of Na⁺, K⁺ and Rb⁺ ions was studied. It was found that an electrode based on thiacalix[4]arene (I) exhibited high selectivity toward Na⁺ ions, and electrodes with (II) and (III) demonstrated a good potentiometric response of the Rb⁺ ion; Rb⁺ can be determined in the presence of excess amounts Na⁺ and K⁺.     

系列新型硫杂杯[4]芳烃氮杂衍生物的合成

在对叔丁基硫杂杯[4]芳烃的下缘1,3位引入芳醛基, 合成了硫杂杯[4]二醛基衍生物2. 化合物2与苯胺、水杨酰肼、烟酰肼、异烟酰肼等通过席夫碱缩合反应得到新型硫杂杯[4]氮杂衍生物3a～3d, 产率分别为83%, 80%, 77%和79%. 化合物2与邻苯二胺、乙二酰肼、丙二酰肼、己二酰肼等通过“1＋1”分子间缩合得到新型1,3-桥联硫杂杯[4]氮杂衍生物4a～4d, 产率53%, 51%, 59%和66%. 新化合物的结构经IR, ¹H NMR, MS和元素分析等证实.     

单氧代-二硒烷基-1, w-二氧取代杯[4]衍生物的合成,结构及萃取性能研究

Novel macrocyclic monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a were synthesized by the reaction of calix[4]arene dibromides 1-5 with the disodium salt of bis（2-selenylethyl）ether in the yields between 28% and 64%. Their structures were characterized by proton and carbon NMR spectra. X-Ray structure analysis of la further confirmed the cone conformation of compounds 1a-5a. An interesting host-guest complex of la with dichloromethane via CH/π and C1/π interactions was elucidated. Extraction experiments showed that these novel monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a had strong extraction ability towards mercury ion. The interaction of Hg^2＋with the calix ligand has also been investigated by 1^H NMR titration.     

Synthesis and Rh(I)‐catalyzed polymerization of 1,3‐diphenylyne–calix[4]arene compounds: Novel conjugated,calixarene‐based polymers

The synthesis of two 1,3‐bis(4‐ethynylbenzyloxy)calix[4]arenes, 5,11,17,23‐tetrakis(1,1‐dimethylethyl)‐25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene ( 1 ) and 25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene ( 2 ), was accomplished through Sonogashira coupling of appropriate calixarene derivatives. Methods for the polymerization of these bifunctional building blocks with Rh(I) as a catalyst, leading ultimately to conjugated polymers having calix[4]arene units incorporated into the main chain, were explored. Calixarenes 1 and 2 were efficiently polymerized with rhodium‐based initiators and afforded the conjugated polymers poly{5,11,17,23‐tetrakis(1,1‐dimethylethyl)‐25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene} ( poly 1 ) and poly{25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene}. Depending on the conditions, high conversions and good yields were obtained. The effects of adding cocatalysts (NHEt₂ and/or PPh₃) were studied in connection with the number‐average molecular weight and the molecular weight distribution of the resultant polymer ( poly 1 ) and tentatively correlated with the formation of low‐molecular‐weight materials. A catalytic system containing triphenylphosphine as the sole additive ([Rh(nbd)Cl]₂; [Rh]/[PPh₃] = 0.5) proved to be the best for the polymerization of p‐tert‐butylcalixarene compound 1 . Linear polymers having high number‐average molecular weights (up to 1.1 × 10⁵ g mol^?1) with low polydispersities were produced under these conditions. For debutylated homologue 2 , its polymerization was best carried out in the absence of any added cocatalyst. A cyclopolymerization route, comprising the intramolecular ring closing of the calix[4]arene pendant ethynyl groups followed by an intermolecular propagation step, is advanced to explain the results. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 7054–7070, 2006     

Bis‐tert‐Alcohol‐Functionalized Crown‐6‐Calix[4]arene: An Organic Promoter for Nucleophilic Fluorination

A bis‐tert‐alcohol‐functionalized crown‐6‐calix[4]arene (BACCA) was designed and prepared as a multifunctional organic promoter for nucleophilic fluorinations with CsF. By formation of a CsF/BACCA complex, BACCA could release a significantly active and selective fluoride source for S_N2 fluorination reactions. The origin of the promoting effects of BACCA was studied by quantum chemical methods. The role of BACCA was revealed to be separation of the metal fluoride to a large distance (>8 Å), thereby producing an essentially “free” F^?. The synergistic actions of the crown‐6‐calix[4]arene subunit (whose O atoms coordinate the counter‐cation Cs⁺) and the terminal tert‐alcohol OH groups (forming controlled hydrogen bonds with F^?) of BACCA led to tremendous efficiency in S_N2 fluorination of base‐sensitive substrates.     

Synthesis of p‐tert‐Butyl‐calix[6] ‐biscrown‐3 via Intramolecular Ring‐closure of 1,4‐Bis (2‐(2‐chloroethoxy) ethoxy) ‐p‐tert‐butyl‐calix[6]arene

With a variation in reaction conditions, 1, 4‐bis (2‐(2‐chloroethoxy)ethoxy)‐calix[6]arene (3) and l,3,5‐tris(2‐(2‐chloroethoxy) ethoxy)‐calix [6] arene (4) or 4 and 4‐chloroethoxyethoxy‐calix[6]crown‐3 (5) were selectively synthesized from p‐tert‐butyl‐calix [6] arene and 2‐(2‐chloroethoxy)ethyltosylate. l,3–4,6‐p‐tert‐butylcalix[6]‐bis‐crown‐3 (6) with (u,u,u,d,d,d) conformation and 1,3–4,5‐p‐tert‐butylcalix[6]‐biscrown‐3 (7) with self‐anchored (u,u, u, u, u, d) conformation were synthesized through an intramolecularly ring‐closing condensation of 1, 4‐bis (2‐(2‐chloroethoxy)ethoxy)‐p‐tert‐butyl‐calix[6]arene (3) in 25% and 15% yield, respectively. Using 5 instead of 3, only 7 was obtained in 65% high yield. 6 and 7 show different complexation properties toward alkali metal and ammonium ions.     

Studies on Properties of p—Nitrophenylazo Calix[4]arene Derivatives

The p-nitrophenylazo calix[4] arene derivatives la-ld with nonlinear optical(NLO)properties were prepared by the diazo-coupling reaction of calix[4]arene with p-nitrophenyl diazonium.The diazotization reaction of p-nltroaniline was caried out with isoamyl nitrite as a source of nitrous acid in EtONa/EtOH under refluxing conditon.X-Ray crystallographic analysis and ^1H NMR sptectra reveal that they exist as cone conformation in crystal state or in soution.HRS measurements at 1064 nm in THF indicate that p-nitrophenylazo calix[4]arenes have higher hyperpolarizability βz values than the corresponding reference compound 4-(4-nitrophenylazo)-2,6-dimethyl-phenol,without red shift of the charge transfer band.The tetrakis p-nitropheylazo calix[4]arene(2)with longer alkyl chains can form monolayer aht the air/water interface.