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J L Wardell

Publications and source records attributed to J L Wardell.

At least 19 recordsLinked to original sources
PubMed2001

Dibromo [N-[2-(diphenylphosphino)benzylidene]-2,6-diisopropylaniline-kappa 2N,]nickel.

In the title compound, [NiBr(2)(C(31)H(32)NP)], (I), the second reported example of a nickel-iminophosphine N,P-chelate in which the Ni atom has tetrahedral coordination, the Ni coordination is distorted as a consequence of the N-Ni-P chelate bite angle of 91.07 (6) degrees compensated by the Br-Ni-Br angle of 126.385 (18) degrees. In (I) and its analogue, viz. dichloro[[2-(4-isobutyloxazol-2-yl)phenyl]diphenylphosphine-N,P]nickel(II), the Ni-N and Ni-P distances are greater and the N-Ni-P ligand bite angles smaller than those observed in a series of related complexes with square-planar nickel.

Journal Article↗
PubMed2001

Dichlorobis(4-methylpentan-2-onato-C4,O)tin(IV) and bis(4-methylpentan-2-onato-C4,O)(2-thioxo-1,3-dithiole-4,5-dithiolato-S,S')tin(IV) at 150 K.

The structures of the ketotins determined here, [SnCl(2)(C(6)H(11)O)(2)] and [Sn(C(3)S(5))(C(6)H(11)O)(2)], respectively, along with that previously reported for [MeC(O)CH(2)CMe(2)](2)SnI(2), are compared with the structures of the analogous estertins [MeOC(O)CH(2)CH(2)](2)SnX(2). Pairwise comparison of the mean ketotin [estertin] Sn-X and Sn-O distances as Sn-X 2.4422 (4) [2.4054 (7) A], 2.4970 (4) [2.471 (2) A] and 2.8463 (4) [2.7788 (8) A] and Sn-O 2.4926 (12) [2.528 (1) A], 2.6110 (11) [2.629 (7) A] and 2.435 (3) [2.525 (4) A] (for X = Cl, S and I, respectively) clearly demonstrates the superior donor ability of the ketotin O atom in chelate formation.

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PubMed2001

Triclinic and orthorhombic polymorphs of 2-iodo-4-nitroaniline: interplay of hydrogen bonds, nitro...I interactions and aromatic pi-pi-stacking interactions.

In the triclinic polymorph of 2-iodo-4-nitroaniline, C(6)H(5)IN(2)O(2), space group P-1, the molecules are linked by paired N-H...O hydrogen bonds into C(8)[R(2)(2)(6)] chains of rings. These chains are linked into sheets by nitro...I interactions, and the sheets are pairwise linked by aromatic pi-pi-stacking interactions. In the orthorhombic polymorph, space group Pbca, the molecules are linked by single N-H...O hydrogen bonds into spiral C(8) chains; the chains are linked by nitro...O interactions into sheets, each of which is linked to its two immediate neighbours by aromatic pi-pi-stacking interactions, so producing a continuous three-dimensional structure.

Aniline Compounds↗
PubMed2001

Hydrogen-bonded chains in N-(2-nitrophenyl)phenylamine.

Molecules of the title compound, C(12)H(10)N(2)O(2), are markedly non-planar. There is an intramolecular N-H...O hydrogen bond, and the molecules are linked into zigzag chains by a single C-H...O hydrogen bond. Comparisons are made with the supramolecular aggregation in isomeric amino-nitro derivatives, and in some N-methylnitroanilines.

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PubMed2001

N,N'-Bis[tris(hydroxymethyl)methyl]-ethanediamide: six O-H...O hydrogen bonds generate only a two-dimensional structure.

Molecules of the title compound, C(10)H(20)N(2)O(8), adopt a conformation which is almost centrosymmetric. The molecules are disordered over two sets of sites with an occupancy ratio of 0.94:0.06. In the major form, there are two intramolecular O-H...O hydrogen bonds [O...O 2.756 (4) and 2.765 (4) A; O-H...O 144 and 146 degrees ], in which the two amidic O atoms act as acceptors. In addition, there are four intermolecular O-H...O hydrogen bonds [O...O 2.650 (3)-2.666 (3) A; O-H...O 158-171 degrees ]; these link each molecule to six others in a continuous sheet structure which contains five distinct ring motifs, two of the S(7) type, two of the R(3)(3)(10) type and one of the R(2)(2)(22) type.

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PubMed2001

Diphenyl(2-thioxo-1,3-dithiole-4,5-dithiolato-S,S')plumbane at 295 K and diphenyl(2-thioxo-1,3-dithiole-4,5-dithiolato-S,S')stannane at 150 K.

Molecules of diphenyl(2-thioxo-1,3-dithiole-4,5-dithiolato-S,S')plumbane, [Pb(C3S5)(C6H5)2], are linked into sheets via two intermolecular Pb...S(thione) interactions of 3.322 (4) and 3.827 (4) A; the Pb centre has a distorted octahedral geometry. In contrast, molecules of diphenyl(2-thioxo-1,3-dithiole-4,5-dithiolato-S,S')stannane, [Sn(C3S5)(C6H5)2], are linked into chains via a single intermolecular Sn--S(thione) interaction of 2.8174 (9) A; the Sn centre has a distorted trigonal-bipyramidal geometry.

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PubMed2001

Solvated and solvent-free forms of N,N'-dithiodiphthalimide.

N,N'-Dithiodiphthalimide, C16H8N2O4S2, crystallizes from ethyl acetate with two independent molecules in the asymmetric unit, in which the N-S-S-N torsion angles are -83.59 (19) and 92.9 (2) degrees. The molecules are linked by C-H...O hydrogen bonds and aromatic pi-pi-stacking interactions into a three-dimensional framework. When crystallized from either dichloromethane or ethanol, solvates are formed in which the molecules of the title compound lie across twofold rotation axes in space group C2/c, with N-S-S-N torsion angles of 93.54 (7) and 96.14 (11) degrees. There are no hydrogen bonds in these solvates, but the molecules are linked by aromatic pi-pi-stacking interactions into chains, between which there are continuous channels. Disordered solvent molecules occupy these channels, which account for ca 20% of the unit-cell volume.

Journal Article↗
PubMed2001

Hydrogen bonding in substituted nitroanilines: isolated nets in 1,3-diamino-4-nitrobenzene and continuously interwoven nets in 3,5-dinitroaniline.

Molecules of 1,3-diamino-4-nitrobenzene, C(6)H(7)N(3)O(2), are linked by N-H.O hydrogen bonds [N.O 2.964 (2) and 3.021 (2) A; N-H.O 155 and 149 degrees] into (4,4) nets. In 3,5-dinitroaniline, C(6)H(5)N(3)O(4), where Z' = 2, the molecules are linked by three N-H.O hydrogen bonds [N.O 3.344 (2)-3.433 (2) A and N-H.O 150-167 degrees] into deeply puckered nets, each of which is interwoven with its two immediate neighbours.

Journal Article↗
PubMed2001

Patterns of soft C-H...O hydrogen bonding in diaryl sulfones.

In bis(4-tolyl) sulfone, C(14)H(14)O(2)S (1), 2,5,4'-trimethyldiphenyl sulfone, C(15)H(16)O(2)S (2), and 4-chlorodiphenyl sulfone, C(12)H(9)ClO(2)S (3), the molecules are linked by soft C-H...O hydrogen bonds into three different types of one-dimensional aggregate: simple chains in (1), molecular ladders in (2) and chains of fused rings in (3). In each of 3,4-dimethyl-4'-chlorodiphenyl sulfone, C(14)H(13)ClO(2)S (4), and 2,5-dimethyldiphenyl sulfone, C(14)H(14)O(2)S (5), the C-H...O hydrogen bonds link the molecules into two different types of two-dimensional sheet, based on a (4,4) net in (4) and a (3,6) net in (5). The patterns of soft C-H...O hydrogen bonds in (1)-(5) are compared with those in other diaryl sulfones, mainly retrieved from the Cambridge Structural Database, whose substitution patterns preclude the formation of hard hydrogen bonds. Observed aggregation modes range from the formation of no C-H...O hydrogen bonds at all, via finite (zero-dimensional) arrays through one-, two- and three-dimensional systems.

Journal Article↗
PubMed2000

Conformational preferences and supramolecular aggregation in 2-nitrophenylthiolates: disulfides and thiosulfonates.

In each of the asymmetrically substituted disulfides 2-nitro-4'-methyldiphenyl disulfide, C(13)H(11)NO(2)S(2) (1), 2-nitro-4'-chlorodiphenyl disulfide, C(12)H(8)ClNO(2)S(2) (2), 2, 4-dinitro-4'-methyldiphenyl disulfide, C(13)H(10)N(2)O(4)S(2) (3), and 2,4-dinitrophenyl-2'-methoxycarbonylmethyl disulfide, C(9)H(8)N(2)O(6)S(2) (4), and in both of the symmetrically substituted disulfides bis(2-nitrophenyl) disulfide, C(12)H(8)N(2)O(4)S(2) (5), and bis(2-nitro-4-trifluoromethylphenyl) disulfide, C(14)H(6)F(6)N(2)O(4)S(2) (6), the 2-nitro groups are essentially coplanar with the adjacent aryl ring and the S atom remote from the nitrated aryl ring is also essentially coplanar and transoid to the nitro group. In S-(2-nitrophenyl) 2-nitrobenzene thiosulfonate, C(12)H(8)N(2)O(6)S(2) (7), which contains three independent molecules in the asymmetric unit, all six of the independent nitro groups are twisted out of the plane of the adjacent aryl rings. The crystal structures of (1)-(3) contain isolated molecules, that of (4) contains centrosymmetric dimers held together by C-H.O hydrogen bonds, while in the structures of (5)-(7), respectively, the C-H.O hydrogen bonds generate one-, two- and three-dimensional arrays. The interplay between molecular conformation and supramolecular aggregation is discussed.

Journal Article↗
PubMed2000

(p-Nitrobenzoato)triphenyltin at 298 K.

The structure at 298 K described here, [Sn(C(6)H(5))(3)(C(7)H(4)NO(4))], completely confirms the results at 173 K obtained previously [Weng, Das & Robinson (1990), Malays. J. Sci. 12, 57]. In both structures, weak interaction between Sn and the carbonyl O atom of the benzoate group provides a distorted trigonal-pyramidal environment at the Sn atom derived from its pseudo-tetrahedral primary coordination in both molecules of the asymmetric unit.

Journal Article↗
PubMed2000

Bis(tetraethylammonium) tetraiodozincate at 150 and 301 K.

The refinements described here for (NEt(4))[ZnI(4)] completely confirm the results previously obtained for the isostructural tetrabromocadmate at room temperature [Geselle & Fuess (1994). Acta Cryst. C50, 1582-1585]. Here again, isolated MX(4) (M = Zn and X = I) tetrahedra are accompanied by two cations in a 'swastika' conformation and a third in a virtually planar trans conformation. One of the former cations is particularly disordered.

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