Synthesis and Crystal Structure of Macrocyclic Cavitand Cucurbit[5]uril and Its Supramolecular Adduct with Cu（Ⅱ）

The first supramolecular adduct (H₃O)₂[Cu(H₂O)₄](SO₄)₂·2(C₃₀H₃₀N₂₀O₁₀)·₂₄(H₂O) based on cucurbit[5]uril was synthesized and characterized by single crystal X‐ray diffraction analysis. In the adduct, copper ion is coordinated by four oxygen atoms from H₂O. The latter links two cucurbit[5]uril molecules due to a complicated hydrogen bonding containing lattice water molecules.     

Synthesis and crystal structure of a supramolecular adduct of the aqua nitrato complex of gadolinium [Gd(NO<Subscript>3</Subscript>)(H<Subscript>2</Subscript>O)<Subscript>7</Subscript>]<Superscript>2+</Superscript> with macrocyclic cavitand cucurbit[6]uril

A supramolecular adduct of gadolinium aqua nitrato complex and cucurbit[6]uril { [Gd(NO₃)(H₂O)₇](C₅H₅N)@(C₃₆H₃₆N₂₄O₁₂)}(NO₃)₂·10H₂O is obtained by slow diffusion of methanol into an aqueous solution containing gadolinium nitrate, pyridine, and cucurbit[6]uril. According to single crystal X-ray diffraction data, water molecules coordinated to metal atom make hydrogen bonds to polarized carbonyl groups of the macrocycle. The heptaaquanitratogadolinium(III) [Gd(NO₃)(H₂O)₇]²⁺ cation is structurally characterized for the first time. Crystal system is triclinic, space group \(P\overline 1 \), a = 12.3137(4) Å, b = 14.2334(5) Å, c = 19.5629(6) Å; α = 80.850(1)°, β = 86.879(1)°, γ = 68.855(1)°; V = 3157.15(18) ų, Z = 2. Oriented hydrogen-bonded chains of alternating cucurbit[6]uril molecules and gadolinium aqua cations form in the crystal structure.     

Crystal structure of a La(III) complex with macrocyclic cavitand cucurbit[6]uril

Slow evaporation in air of a lanthanum nitrate solution containing macrocyclic cavitand cucurbit[6]uril yields a complex of the composition of [La(H₂O)₆(X@C₃₆H₃₆N₂₄O₁₂)(NO₃)](NO₃)₂· 6.96H₂O (X = 0.5C₅H₅N + 0.5H₂O). The complex is structurally characterized using single crystal X-ray diffraction. Lanthanum atoms are coordinated with oxygen atoms of carbonyl groups of cucurbit[6]uril portals. The compound crystallizes in the orthorhombic crystal system, space group Pnn2, unit cell parameters (150 K): a = 11.997(2) Å, b = 17.093(3) Å, c = 14.133(3) Å, V = 2899.3(10) ų, Z = 2. Lanthanum atoms are disordered, alternative positions being related by the two-fold axis. The complex has an island structure. A pyridine molecule occupies an internal cavity of one half of cucurbit[6]uril molecules, while a water molecule occupies the other.     

Synthesis and Crystal Structure of Macrocyclic Cavitand Cu-curbit[5]uril and Its Supramolecular Adduct with Cu(II)

Introduction The cucurbit[n]urils (CB[n]s) are a kind of cyclic methylene-linked glycoluril oligomers and possess a characteristic annular shape, with two identical car-bonyl-fringed portals.1-3 As the most common cucurbi-turil, CB[6], has been widely studied in supramolecular chemistry by the groups of Mock4 and Kim.5 Recently, other CB[n] (n=5, 7, 8), the molecular recognition properties of which are different from those of CB[6] itself, have been extensively utilized in molecular rec-og…     

Synthesis and crystal structures of PrIII and NdIII complexes with the macrocyclic cavitand cucurbit[6]uril

The [{Pr(NO₃)₂(H₂O)₃}{Pr(NO₃)(H₂O)₄} (C₃₆H₃₆N₂₄O₁₂)](NO₃)₃·4H₂O and [{Nd(NO₃)(H₂O)₄} ₂(NO₃@C₃₆H₃₆N₂₄O₁₂)][Nd(NO₃)₆] complexes were prepared by heating a mixture of lanthanide nitrates, cucurbit[6]uril, and water in a sealed tube. X-ray diffraction study demonstrated that the metal atoms in the former complex are linked to the macrocycle through tridentate coordination of the portal oxygen atoms of cucurbit[6]uril to the praseodymium(III) cation. The neodymium(III) complex is the first example of lanthanide compounds with cucurbit[6]uril belonging to coordination polymers. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1511–1517, September, 2006.     

Synthesis and crystal structures of supramolecular compounds of polynuclear aluminum(III) aqua hydroxo complexes with cucurbit[6]uril

Supramolecular compounds of the di-, trideca-, and triacontanuclear aluminum aqua hydroxo complexes, viz., [Al₂(OH)₂(H₂O)₈]⁴⁺, [Al₁₂(AlO₄)(OH)₂₄(H₂O)₁₂]⁷⁺, and [Al₃₀O₈(OH)₅₆(H₂O)₂₆]¹⁸⁺, respectively, with the organic macrocyclic cavitand cucurbit[6]uril (C₃₆H₃₆N₂₄O₁₂) were prepared by evaporation of aqueous solutions of aluminum nitrate and cucurbit[6]uril after the addition of pyridine, ammonia, KOH, or NaOH at pH 3.1–3.8. X-ray diffraction study demonstrated that the aqua hydroxo complexes are linked to the macrocycle through hydrogen bonds between the hydroxo and aqua ligands of the polycations and the portal oxygen atoms of cucurbit[6]uril. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 261—268, February, 2006.     

Synthesis and crystal structures of supramolecular adducts of molybdenum and tungsten selenide aqua complexes with macrocyclic cavitand cucurbituril

The supramolecular compounds {[W₃Se₄Cl₃(H₂O)₆]₂[PyHC₃₆H₃₆N₂₄O₁₂]}Cl₃·18H₂O (1) and {[Cl₃SnMo₃Se₄Cl₃(H₂O)₆][Cl₃SnMo₃Se₄Cl₂(H₂O)₇](C₃₆H₃₆N₂₄O₁₂)}Cl·26H₂O (2) were isolated from solutions of the selenium-containing tungsten and molybdenum clusters [W₃Se₄(H₂O)₉]⁴⁺ and [Cl₃SnMo₃Se₄(H₂O)₉]³⁺, respectively, and organic cavitand cucurbituril. X-ray diffraction analysis demonstrated that the macrocylcic cucurbituril molecule is coordinated on both sides by the cluster cations through the formation of complementary hydrogen bonds. Compound 1 has a chain structure stabilized by Se...Se interactions between the adjacent cluster cores. In compound 2, the bridging ₂-selenium atoms of the cluster fragment Mo₃Se₄ are coordinated to the tin atom of the SnCl₃ ^– ligand, thus losing the ability to be involved in Se...Se interactions.     

六元瓜环与磺基水杨酸主客体配合物的晶体结构

合成了六元瓜环与磺基水杨酸主客体配合物,并测定了其单晶结构.晶体结构表明六元瓜环包结了3个水分子,磺基水杨酸位于六元瓜环的外侧,且与水分子通过氢键与六元瓜环相连,瓜环之间通过端口的羰基O原子、磺基水杨酸以及水分子间的氢键作用形成一维超分子.     

Use of the macrocyclic ligand cucurbit[6]uril for isolation of tetranuclear lanthanide aquahydroxo-carboxylate complexes from aqueous solutions

The tetranuclear lanthanide complexes {[Ln₄(μ₃-OH)₄(μ₂-OH)₂(C₅NH₄COO)₂ (H₂O)₄-(C₃₆H₃₆N₂₄O₁₂)₂][Ln(H₂O)₈]_1.5[Ln(H₂O)₆(NO₃)₂]_0.5} (NO₃)₉·nH₂O (Ln = Ho, Gd, or Er) were prepared by heating (130 °C) aqueous solutions of lanthanide nitrates, cucurbit[6]uril (C₃₆H₃₆N₂₄O₁₂), and 4-cyanopyridine. The tetradentate coordination of the macrocyclic cucurbit[6]uril ligands through the portals leads to the formation of sandwich compounds, in which the tetranuclear hydroxo complex is located between two macrocyclic molecules. The polynuclear complexes are additionally stabilized by the chelating effect of the isonicotinate ligands generated by hydrolysis of 4-cyanopyridine. In the complexes, the aromatic moiety of the isonicotinate ion is encapsulated into the hydrophobic inner cavity of cucurbit[6]uril. In the absence of cucurbit[6]uril, the reaction with 4-cyanopyridine produces only the polymeric complexes [Nd(C₅NH₄COO)₃(H₂O)₂] and [Ln(C₅NH₄COO)₂(H₂O)₄]NO₃ (Ln = Pr, Sm, or Gd), whose structures were established by X-ray diffraction. In water and aqueous solutions of nonionic and cationic surfactants, irreversible changes of the tetranuclear fragment of the complex (Ln = Gd) were observed after storage for two days, whereas the anionic surfactant stabilizes the complexes. Dedicated to Academician O. M. Nefedov on the occasion of his 75th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1885–1894, November, 2006.     

Synthesis and crystal structures of sumpramolecular compounds of cucurbit[n]urils (n = 6, 8) with polynuclear strontium aqua complexes

Crystals of the {[Sr₄(H₂O)₁₂(NO₃)₄](C₃₆H₃₆N₂₄O₁₂)}(NO₃)₄·3H₂O and {[Sr₂(H₂O)₁₂][Sr(H₂O)₃(NO₃)₂]₂(C₄₈H₄₈N₃₂O₁₆)}(NO₃)₄·8H₂O were prepared by slow concentration of aqueous solutions containing strontium nitrate and macrocyclic cavitands, viz., cucurbit[6]uril and cucurbit[8]uril ([C₆H₆N₄O₂] _n , n = 6 and 8), respectively. According to the results of X-ray diffraction analysis, the crystal structures of these supramolecular compounds are built from polymeric chains, which consist of the alternating cucurbit[n]uril molecules and Sr²⁺ cations linked through the bridging aqua ligands and nitrate anions. The supramolecular compound of cucurbit[8]uril provides the first example of compounds in which this macrocycle is bound to metal aqua complexes.     

2,7-萘二磺酸阴离子导向五元瓜环基超分子自组装体的制备及其荧光检测性能

通过引入2,7-萘二磺酸(2,7-NDA^2-)阴离子作为结构导向剂,与五元瓜环(Q[5])和过渡金属离子(Co²⁺、Ni²⁺、Zn²⁺、Cd²⁺)在水热条件下制备了4种新颖的Q[5]基超分子自组装体(Q[5]-SA),即{[M (H₂O)₄(Q[5])]·(NDA)}·xH₂O (M=Co (1)、Ni (2)、Zn (3))和{[Cd₂Cl₂(H₂O)₄(Q[5])]·(NDA)}·13H₂O (4)。单晶X射线衍射测试结果表明,自组装体1~3同构,其中Q[5]仅一端的部分端口羰基氧原子与金属离子配位形成简单配合物;而4中Q[5]的2个端口均与金属离子Cd²⁺配位形成了一维配位链。在自组装体1~4中,配体2,7-H₂NDA均全脱质子,形成2,7-NDA^2-阴离子平衡体系电荷,但均未能与金属离子配位,而在2,7-NDA^2-阴离子与Q[5]外壁之间的瓜环外壁作用下进一步形成三维超分子结构。此外,还研究了自组装体1和4的荧光传感性能,结果表明它们都能够作为抗生素诺氟沙星(NFX)的比率型荧光探针。     

2，7-萘二磺酸导向构筑的五元瓜环-碱金属及碱土金属基超分子自组装体及其溶剂识别

以2,7-萘二磺酸（2,7-H₂NDA）作为结构导向剂,与五元瓜环（Q[5]）和碱金属、碱土离子（K⁺、Rb⁺、Mg²⁺、Ca²⁺）在水热条件下制备出了4种新颖的Q[5]基超分子自组装体[K₂（H₂O）₄（Q[5]）]（2,7-NDA）·4H₂O （1）、[Rb₂（H₂O）₅（Q[5]）]（2,7-NDA）·3H₂O （2）、[Mg （H₂O）₄（Q[5]）]（2,7-NDA）·8H₂O （3）和[Ca （H₂O）₄（Q[5]）]（2,7-NDA）·10H₂O （4）。单晶X射线衍射测试结果表明,自组装体1和2具有相同的结构： Q[5]分子与金属离子配位形成的是“分子胶囊”;而在3中Q[5]与Mg²⁺配位形成的是1：1型简单配合物结构;在自组装体4中,Q[5]与Ca²⁺配位形成的是一维Q[5]-Ca²⁺配位聚合物链结构。这些结构中2,7-NDA^2-阴离子平衡了体系电荷,且通过其与瓜环外壁之间的弱相互作用,促进自组装体最终构筑成三维超分子结构。此外,还研究了自组装体4的溶剂识别荧光传感性能,结果表明其能够作为有机溶剂丙酮和DMF的猝灭型荧光探针。     

(英)两个基于大环配体五员瓜环的异核金属配合物的合成及晶体结构

设计并合成了两个五员瓜环(Q[5])桥联K+和Na+形成的新型配合物[K(H2O)2Na(H2O)Q[5]](ClO4)2·6H2O(1),[KNaH(H2O)4Q[5]]n(ClO4)3n·3nH2O(2)。利用单晶X射线衍射进行结构测定,结果表明,配合物1中Q[5]起着一个双五齿配体的作用,每个端口的5个羰基氧原子分别和钾离子和钠离子配位,形成分子胶囊;配合物2中每个钾离子分别通过与相邻的2个Q[5]端口的相邻一对羰基氧原子配位,使得配合物形成一维链状结构,同时Q[5]还提供1个羰基氧原子与Na+配位,氢键使得配合物形成三维超分子结构。     

Synthesis and crystal structure of a supramolecular adduct of the cubane cluster [CIPdMo3Se4(H2O)7Cl2]+ with macrocyclic cavitand cucurbituril

A new heterometallic selenide-bridged 60-electron complex containing the cubane cluster fragment [M0₃(μ₃-Se)₄Pd]^4τ was prepared by heating a solution of [Mo₃Se₄(H₂O)₉]Cl₄ and palladium black in 2M HCl. The cluster complex was isolated from aqueous solutions as a hydrolytically stable supramolecular adduct with macrocyclic cavitand cucurbituril. The molecular and crystal structure of {[ClPdMo₃Se₄(H₂O)₇Cl₂](C₃₆H₃₆N₂₄O₁₂)Cl}·7H₂O were established by X-ray diffraction analysis. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1905–1909, November, 2000.     

Synthesis and the crystal structure of a supramolecular adduct of the [Mo3O4(H2O)6Cl3]+ cluster complex with macrocyclic cavitand cucurbituril

The crystalline supramolecular compound of composition {(C₃₆H₃₆N₂₄O₁₂)[Mo₃O₄(H₂O)₆Cl₃]₂}Cl₂·14H₂O was obtained by slow concentration of a hydrochloric solution of the cluster aqua complex [Mo₃O₄(H₂O)₉]⁴⁺ and macrocyclic cavitand cucurbituril (C₃₆H₃₆N₂₄O₁₂). The molecular and crystal structure of the supramolecular adduct was established by X-ray diffraction analysis.     

Tuning thermal gelling behavior of <Emphasis Type="Italic">N</Emphasis>-isopropylacrylamide based copolymer through introducing cucurbit[8]uril ternary complex on side-chain

Thermo-gelation polymers have attracted increasing attention over decades. However, rare facile tuning method of sol-gel transition temperature restricted the wider application. Preceding study indicated that supramolecular interactions demonstrated a powerful means to control the structure and property of polymeric materials. Here we designed an N-isopropylacrylamide (NIPAM) based thermo-sensitive copolymer with naphthyl (Np) on its side chain. Positive-charged side-chain ternary complex was formed with cucurbit[8]uril (CB[8]) and methylviologen (MV²⁺) via CB[8]-enhanced intermolecular charge-transfer (CT) interaction. Introducing the ternary complex CB[8]/MV²⁺/Np on side-chain altered microstructure of macromolecular chains and led to a strong tendency for thermo gelation. Altering content of CB[8] and MV²⁺ changed content of the positive-charged side-chain ternary complex and varied gelation temperature. Therefore, introducing supramolecular interaction endowed the hydrogel with tunable gelation property.     

Thermodynamics of ion exchange of H<Superscript>+</Superscript> by Na<Superscript>+</Superscript> or NH<Subscript>4</Subscript><Superscript>+</Superscript> on ion-exchange resins based on <Emphasis Type="Italic">C</Emphasis>-tetramethylcalix[4]resorcinarene

The corrected selectivity coefficients of the ion exchange H⁺-Na⁺ and H⁺-NH₄ ⁺ on ion-exchange resins based on C-tetramethylcalix[4]resorcinarene were calculated from the experimental data obtained from studying ion-exchange equilibria. The preference of the ion-exchange resins for cations increases in the sequence: Na⁺ < NH₄ ⁺ < < H⁺, and the ion-exchange resin based on (2-furyl)hydroxymethyltetramethylcalix[4]resorcinarene has a higher preference for ammonium cations. According to the results of microcalorimetric measurements, the exchange H⁺-Na⁺ on this ion-exchange resin is accompanied by the highest change in the differential enthalpy. It follows from the quantum-chemical calculations that the introduction of a (2-furyl)hydroxymethyl group into the structure of the polymer induces additional electrostatic interactions between an ammonium cation and an elementary unit of the ion-exchange resin.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2560–2563, December, 2004.     

A dinuclear molybdenum cluster containing i-mnt ligand: synthesis and crystal structure of [Mo_2S_4(i-mnt)_2] (Et_4N)_2

A dinuclear molybdenum(V) cluster compound (Et4N)2[Mo2S4(i-mnt)2] (i-mnt=l,l-dicyanoethylene-2,2-dithiol, (S2C=C(CN)2]2-) has been prepared by the ligand substitution reaction of Mo2S4(iso-pr2dtp)2 (iso-pr2dtp=S2P(OC3H7)2-) with K2(i-mnt) in the presence of Bt4NI. This cluster was characterized by inrrared spectrum, UV-Vis spectrum and single crystal structure analy-sis. The cluster anion [Mo2S4(i-mnt)2]2- possesses C, symmetry with a crystallographic mirror plane through two bridging S atoms. By the S....S supramolecular interactions between two adjacent cluster anions the [Mo2S4(i-mnt)2]2- anions are linked to form infinite chains along the b axis. Crystal data: monoclinic, space group C2/m, a=1.8748(6), b=1.5360(4), c=1.4322(5) nm, ,β=112.02(2)°, V=3.823(4) nm3, Z=4, Dc=1.50 g/cm3. The final R=0.038 and .RW=0.053 for 3015 observed unique reflections.     

Inclusion of nickel(<Emphasis Type="SmallCaps">II</Emphasis>) and copper(<Emphasis Type="SmallCaps">II</Emphasis>) complexes with aliphatic polyamines in cucurbit[8]uril

The inclusion compound of macrocyclic cavitand cucurbit[8]uril (CB[8]) with the nickel(II) complex containing the tetraazamacrocyclic ligand cyclam, {[Ni(cyclam)]@CB[8]}Cl₂··16H₂O (1), and the inclusion compounds of CB[8] with the copper(II) bis-ethylene-diamine complex, {trans-[Cu(en)₂(H₂O)₂]@CB[8]}Cl₂·{CB[8]}·42H₂O (2a) and {trans-[Cu(en)₂(H₂O)₂]@CB[8]}Cl₂·17H₂O (2b), were synthesized and characterized by X-ray diffraction analysis, IR and ESR spectroscopy, and electrospray mass spectrometry. Guest—host inclusion compounds can be directly synthesized starting from a metal complex and cucurbit[8]uril, as was exemplified by the preparation of compounds 2a and 2b.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2414–2419, November, 2004.     

A concise,efficient and versatile synthesis of amino‐substituted benzo[b]pyrimido[5,4‐f]azepines: synthesis and spectroscopic characterization,together with the molecular and supramolecular structures of three products and one intermediate

A concise, efficient and versatile synthesis of amino‐substituted benzo[b]pyrimido[5,4‐f]azepines is described: starting from a 5‐allyl‐4,6‐dichloropyrimidine, the synthesis involves base‐catalysed aminolysis followed by intramolecular Friedel–Crafts cyclization. Four new amino‐substituted benzo[b]pyrimido[5,4‐f]azepines are reported, and all the products and reaction intermediates have been fully characterized by IR, ¹H and ¹³C NMR spectroscopy and mass spectrometry, and the molecular and supramolecular structures of three products and one intermediate have been determined. In each of N,2,6,11‐tetramethyl‐N‐phenyl‐6,11‐dihydro‐5H‐benzo[b]pyrimido[5,4‐f]azepin‐4‐amine, C₂₂H₂₄N₅, (III), 4‐(1H‐benzo[d]imidazol‐1‐yl)‐6,11‐dimethyl‐6,11‐dihydro‐5H‐benzo[b]pyrimido[5,4‐f]azepine, which crystallizes as a 0.374‐hydrate, C₂₁H₁₉N₅·0.374H₂O, (VIIIa), and 6,7,9,11‐tetramethyl‐4‐(5‐methyl‐1H‐benzo[d]imidazol‐1‐yl)‐6,11‐dihydro‐5H‐benzo[b]pyrimido[5,4‐f]azepine, C₂₄H₂₅N₅, (VIIIc), the azepine ring adopts a boat conformation, but with a different configuration at the stereogenic centre in (VIIIc), as compared with (III) and (VIIIa). In the intermediate 5‐allyl‐6‐(1H‐benzo[d]imidazol‐1‐yl)‐N‐methyl‐N‐(4‐methylphenyl)pyrimidin‐4‐amine, C₂₂N₂₁N₅, (VIIb), the immediate precursor of 4‐(1H‐benzo[d]imidazol‐1‐yl)‐6,8,11‐trimethyl‐6,11‐dihydro‐5H‐benzo[b]pyrimido[5,4‐f]azepine, (VIIIb), the allyl group is disordered over two sets of atomic sites having occupancies of 0.688 (5) and 0.312 (5). The molecules of (III) are linked into chains by a C—H…π(pyrimidine) hydrogen bond, and those of (VIIb) are linked into complex sheets by three hydrogen bonds, one of the C—H…N type and two of C—H…π(arene) type. The molecules of the organic component in (VIIIa) are linked into a chain of rings by two C—H…π(arene) hydrogen bonds, and these chains are linked into sheets by the water components; a single weak C—H…N hydrogen bond links molecules of (VIIIc) into centrosymmetric R₂²(10) dimers. Comparisons are made with some related compounds.