Dihydro[2.2.2]cryptand di-mu-hydroxo-bis[bis(nitrato-kappa 2O,O')dioxouranium(VI)] monohydrate

In the title dinuclear uranyl complex, (C(18)H(38)N(2)O(6))[(UO(2))(2)(NO(3))(4)(OH)(2)].H(2)O, each pair of uranyl ions in the two independent centrosymmetric dianionic dimers is bridged by the two hydroxide ions, with the nitrate ions ensuring equatorial hexagonal coordination. The dihydro[2.2.2]cryptand (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) dication presents an 'in-in' conformation (endo protonation) and it is hydrogen bonded to the hydroxide ions, either directly or via a water molecule, resulting in the formation of linear hydrogen-bonded polymers.

(+/-)-6-tert-butyl-8-hydroxymethyl-2-phenyl-4H-1,3-benzodioxin and 2,2,2',2',6,6'-hexamethyl-8,8'-methylenebis(4H-1,3-benzodioxin)

Two compounds containing 1,3-benzodioxin groups are reported, namely (+/-)-6-tert-butyl-8-hydroxymethyl-2-phenyl-4H-1,3-benzodioxin, C(19)H(22)O(3), (I), and 2,2,2',2',6,6'-hexamethyl-8,8'-methylenebis(4H-1,3-benzodioxin), C(23)H(28)O(4), (II). The hydroxy groups of neighbouring molecules in (I) are hydrogen bonded to each other, giving rise to double-row chains. The molecule in (II) adopts a 'butterfly' conformation, with the O atoms in distal positions. In both compounds, the dioxin rings are in distorted half-chair conformations.

Hydrogen-bonded assemblages in 2,6-bis(hydroxymethyl)-4-R-phenol, with R = methyl, methoxy, phenoxy and 1-(4-methoxyphenyl)-1-methylethyl

Four derivatives of 2,6-bis(hydroxymethyl)phenol, with various para substituents, have been investigated; these are 2,6-bis(hydroxymethyl)-4-methylphenol, C(9)H(12)O(3), (I), 2,6-bis(hydroxymethyl)-4-methoxyphenol, C(9)H(12)O(4), (II), 2,6-bis(hydroxymethyl)-4-phenoxyphenol, C(14)H(14)O(4), (III), and 2,6-bis(hydroxymethyl)-4-[1-(4-methoxyphenyl)-1-methylethyl]phenol, C(18)H(22)O(4), (IV). All four structures display hydrogen-bonding networks resulting in sheets, with possible weak inter-sheet pi-pi interactions in one case. In all the structures but one, the molecules form centrosymmetric dimeric subunits held together by two hydrogen bonds between the hydroxymethyl groups and, in two cases, by probable pi-pi interactions.

Two triethylammonium ion complexes of monoanionic calix[4]arene

Two complexes between mono-deprotonated calix[4]arene and Et(3)HN+ are reported. The first, triethylammonium 26,27,28-trihydroxypentacyclo[19.3.1.1(3,7).1(9,13).1(15,19)]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaen-25-olate, C(6)H(16)N+ x C(28)H(23)O(4)-, comprises only the cationic and anionic species, whereas the second, tris(triethylammonium) tris[26,27,28-trihydroxypentacyclo[19.3.1.1(3,7).1(9,13).1(15,19)]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaen-25-olate] acetonitrile solvate, 3C(6)H(16)N+ x 3C(28)H(23)O(4)(-) x C(2)H(3)N, comprises one acetonitrile solvent molecule for three such units. In both cases, the units are stacked in columns so that the ammonium cation is hydrogen bonded to a phenolic or phenolate O atom of one molecule and included in the hydrophobic cavity of another neighbouring calixarene. The short contacts present indicate that cation* * *pi and C-H* * *pi interactions are likely to be involved in the inclusion phenomena.

Syntheses, X-ray crystal structures, and magnetic properties of novel linear M2[II]U[IV] complexes (M=Co, Ni, Cu, Zn)

Attempts to prepare heterobimetallic complexes in which 3d and uranium magnetic ions are associated by means of the Schiff bases H(2)L(i) derived from 2-hydroxybenzaldehyde or 2-hydroxy-3-methoxybenzaldehyde were unsuccessful because of ligand transfer reactions between [ML(i)] (M=Co, Ni, Cu) and UCl(4) that led to the mononuclear Schiff base complexes of uranium [UL(i)Cl(2)]. The crystal structure of [UL(3)Cl(2)(py)(2)] [L(3)=N,N'-bis(3-methoxysalicylidene)-ethylenediamine; py=pyridine] was determined. The hexadentate Schiff base ligand N,N'-bis(3-hydroxysalicylidene)-2,2-dimethyl-1,3-propanediamine (L) was useful for the synthesis of novel trinuclear complexes of the general formula [[ML(py)](2)U] (M=Co, Ni, Zn) or [[CuL(py)]M'[CuL]] (M'=U, Th, Zr) by reaction of [M(H(2)L)] with [M'(acac)(4)] (acac=MeCOCHCOMe). The crystal structures of the Co(2)U, Ni(2)U, Zn(2)U, Cu(2)U, and Cu(2)Th complexes show that the two ML fragments are orthogonal, being linked to the central actinide ion by the two pairs of oxygen atoms of the Schiff base ligand. In each compound, the UO(8) core exhibits the same dodecahedral geometry, and the three metals are linear. The magnetic study indicated that the two Cu(2+) ions are not coupled in the Cu(2)Zr and Cu(2)Th compounds. The magnetic behavior of the Co(2)U, Ni(2)U, and Cu(2)U complexes was compared with that of the Zn(2)U derivative, in which the paramagnetic 3d ion was replaced with the diamagnetic Zn(2+) ion. A weak antiferromagnetic coupling was observed between the Ni(2+) and the U(4+) ions, while a ferromagnetic interaction was revealed between the Cu(2+) and U(4+) ions.

First- and second- sphere coordination of the uranyl ion by bis[2-(2-hydroxyphenoxy)ethoxy]ethane

Uranyl nitrate hexahydrate reacts with bis[2-(2-hydroxyphenoxy)ethoxy]ethane (C(18)H(22)O(6)), denoted LH(2) hereafter, in the presence of triethylamine to give triethylammonium aqua[2,2'-(3,6-dioxaoctane-1,8-diyldioxy)diphenolato-kappa(2)O,O'](nitrato-kappa(2)O,O')dioxouranium(VI), (Et(3)NH)[UO(2)(H(2)O)L(NO(3))], which possesses a symmetry plane. The uranyl ion is coordinated to the two phenoxide O atoms, a nitrate ion and a water molecule (first sphere); the water molecule is itself held in the crown ether chain by hydrogen-bonding interactions, thus ensuring second-sphere coordination by the ligand L.

2,3,6,7-Tetrahydroxy-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene bis(1,4-dioxane) solvate

2,3,6,7-Tetrahydroxy-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene crystallizes with 1,4-dioxane to give a bis-solvate, C(18)H(18)O(4).2C(4)H(8)O(2). The bis(catechol) molecule is located on a twofold axis and the two aromatic rings form a dihedral angle of 130.61(4) degree. Hydrogen bonds are formed between the hydroxyl groups and either a neighbouring bis(catechol) molecule or the ether-O atom of a dioxane molecule.

An ion pair formed by protonated Fe(cp*py)2 and the octanuclear cluster U8Cl24O4(cp*py)2 [cp*py is tetramethyl-5-(2-pyridyl)cyclopentadiene]

In bis[1,1',2,2',3,3',4,4'-octamethyl-5-(2-pyridinio)-5'-(2-pyridyl)ferrocene] di-mu(3)-chloro-hexadeca-mu(2)-chloro-hexachlorodi-mu(4)-oxo-di-mu(3)-oxo-bis[(eta(5),kappaN)-1,2,3,4-tetramethyl-5-(2-pyridyl)cyclopentadienyl]octauranium(IV) dichloromethane tetrasolvate, [Fe(C(14)H(17)N)(C(14)H(16)N)](2)[U(8)Cl(24)O(4)(C(14)H(16)N)(2)].4CH(2)Cl(2), (I), two protonated Fe(cp*py)(2) units [cp*py is tetramethyl-5-(2-pyridyl)cyclopentadiene] form an ion pair with the dianionic centrosymmetric cluster U(8)Cl(24)O(4)(cp*py)(2). The latter is the highest nuclearity assemblage in the chemistry of uranium (non-uranyl) compounds reported to date.

A dinuclear uranium(IV) complex of the chelating ligand 1,2,3,4-tetramethyl-5-(2-pyridyl)cyclopentadiene

The ligand 1,2,3,4-tetramethyl-5-(2-pyridyl)cyclopentadiene (cp*py) forms a dinuclear complex with U(IV), i.e. di-mu-oxo-bis[chloro(diethyl ether-kappaO)[(eta5,kappaN)-1,2,3,4-tetramethyl-5-(2-pyridyl)cyclopentadienyl]uranium(IV)], [U2Cl2O2(C14H16N)2(C4H10O)2], in which cp*py acts as a chelating ligand, being bound to the metal atom by the cyclopentadienyl unit and also by the N atom of the pyridyl ring.

Bis[2-(2-hydroxyphenoxy)ethyl] ether methanol solvate

The title compound, 2,2'-(3-oxapentane-1,5-diyldioxy)diphenol, crystallizes as a methanol solvate, C16H18O5*CH4O. The methanol molecule, roughly perpendicular to the mean plane of the polyether molecule, is hydrogen bonded to the two polyether OH groups and to the central ether O atom. Possible C-H...pi intermolecular interactions are present.

Methoxy-ether and crown-ether derivatives of tetrahomodioxa- and octahomotetraoxacalix[4]arenes

Three methoxy-ether and one methoxy-ether/crown-ether derivatives of p-tert-butyltetrahomodioxa- and p-R-octahomotetraoxacalix[4]arenes (R = methyl, tert-butyl, H) have been investigated. The first three compounds, 7,15,21,27-tetra-tert-butyl-29,30,31,32-tetramethoxy-3,11-dioxapentacyclo[23.3.1.1(5,9).1(13,17).1(19,23)]ditriaconta-1(29),5,7,9(30),13,15,-17(31),19,21,23(32),25,27-dodecaene, C(50)H(68)O(6), 33,34,35,36-tetramethoxy-7,15,23,31-tetramethyl-3,11,19,27-tetraoxapentacyclo[27.3.1.1(5,9).1(13,17).1(21,25)]hexatriaconta-1(33),5,7,9(34),13,15,17(35),21,23,25(36),29,31-dodecaene, C(40)H(48)O(8), and 7,23-di-tert-butyl-33,34,35,36-tetramethoxy-3,11,19,27-tetraoxapentacyclo[27.3.1.1(5,9).1(13,17).1(21,25)]hexatriaconta-1(33),5,7,9(34),13,15,17(35),- 21,23,25(36),29,31-dodecaene, C(44)H(56)O(8), in the partial-cone or 1,2-alternate conformations, present the common feature of methoxy-ether self-inclusion, while the fourth, 42,43-dimethoxy-7,15,23,31-tetramethyl-3,11,19,27,34,37,40-heptaoxahexacyclo[15.15.9.1(5,9).1(21,25).0(13,41).0(29,33)]tritetraconta-5(42),6,8,13(41),14,16,21(43),22,24,29(33),30,32-dodecaene, C(42)H(50)O(9), adopts the 1,3-alternate conformation owing to the presence of a 1,3-polyether chain.

p-methyltetrahomodioxacalix[4]arene

The title compound, 7,13,21,27-tetramethyl-3,17-dioxapentacyclo[23.3.1.1(5,9).1(11,15).1(9,23)]ditriaconta-1(29),5,7,9(30),11(31),-12,14,19(32),20,22,25,27-dodecaene-29,30,31,32-tetraol, C34H36O6, assumes in the solid state a very distorted cone-like conformation stabilized by intramolecular simple and bifurcated hydrogen bonds involving both phenolic and ether O atoms. One part of the molecule, comprising an ether link, is included in the cavity of an adjacent calixarene related by a screw axis, giving rise to a one-dimensional self-inclusion polymer.