Showing papers by "Karna Wijaya published in 2001"

Polysulfonylamine, CXLIII [1], Rolle schwacher Wasserstoffbrücken (C - H···O) in den Kristallstrukturen von 2,6-Dimethylpyridinium-, 1-Hydroxypyridinium- und Imidazolium-dimesylamid / Polysulfonylamines, CXLIII [1], Role of Weak Hydrogen Bonds (C - H···O) in the Crystal Structures of 2,6-Dimethylpyridinium , 1-Hydroxypyridinium and Imidazolium Dimesylamide

Abstract: In order to study hydrogen bonding networks in ionic crystals, low-temperature X-ray structures were determined for three onium salts of general formula BH+(MeSO2)2N- , where BH+ is 2,6-dimethylpyridinium (1; monoclinic, space group P21/c, Z′ = 1), 1-hydroxypyridinium (2; triclinic, P1̅, Z′ = 1), or imidazolium (3; monoclinic, Cc, Z′ = 1). The asymmetric units consist of cation-anion pairs assembled in 1 and 3 by ordinary N+ - H···N hydrogen bonds, in 2 by a very short N+ - O - H···N- bond belonging to the class (+/-)CAHB [H···O 148(3), O···N 253.5(2) pm, O - H···N 175(3)°]. The second N -H donor of the imidazolium ion is involved in a nearly symmetric N - H (···O)2 three-centre bond to two different anions. In the pyridine derivatives, the (MeSO2 )2N- ions are associated via short C(sp3) - H···O contacts to form a three-dimensional framework of corrugated and cross-linked layers (1) or an assembly of discrete corrugated layers (2). As a common feature, these anion substructures are pervaded by hexagonal channels parallel to x, each one accommodating two stacks of cations that are linked to the channel walls by the unique strong hydrogen bond and a set of short Car - H···O contacts; moreover, cations drawn from adjacent stacks in structure 2 create inversion-symmetric dimers based upon a short Car - H···O(H) - N interaction. In contrast, the structure of 3 displays planar anion layers assembled by short C(sp3 ) - H···O contacts, intercalating the cations with their ring planes perpendicular to the layer planes and binding them by means of the strong hydrogen bonds and three Car -H···O interactions. All C - H···O taken into consideration have normalized parameters d( H···O) ≤ 267 pm and θ(C - H···O) ≥ 121°.

Polysulfonylamine, CXLII [1]. Ein supramolekulares Monomer-Dimer-Paar: Starke und schwache Wasserstoffbrücken in den Kristallstrukturen von Pyridinium-dimesylamid und 4,4´-Bipyridindiium-bis(dimesylamid) / Polysulfonylamines, CXLII [1]. A Supramolecular Monomer-Dimer Pair: Strong and Weak Hydrogen Bonding in the Crystal Structures of Pyridinium Dimesylamide and 4,4´-Bipyridinediium Bis(dimesylamide)

Abstract: In order to study packing arrangements and hydrogen bonding networks, low-temperature X-ray structures were determined for pyH⁺(MeSO₂)₂N⁻ (M, orthorhombic, space group P2₁2₁2₁, Z′ = 1) and 4,4′-bipyH₂²⁺ ·(MeSO₂)₂N⁻ (D, monoclinic, C2/c, Z′ = 0.5). The structures consist of ionic formula entities assembled by N+-H···N⁻ hydrogen bonds; the dication in D displays crystallographic C₂ symmetry and has its two pyridyl moieties twisted by 43.9°. According to the packing architectures, D represents a supramolecular dimer of the monomeric congener M. In particular, the (MeSO₂)₂N⁻ ions of the M structure are associated via short C(sp³) - H···O contacts to form a diamondoid network, whereas in D a topologically congruent framework is constructed from weakly hydrogen-bonded [(MeSO₂)N⁻]₂ nodes. Hexagonal channels in the anion substructures each include two adjacent stacks of monomeric pyH⁺ or “dimeric” 4,4-bipyH₂²⁺ cations that are linked to the channel walls by the strong hydrogen bond(s) and a set of short Cₐᵣ-H···O contacts. All C - H···O taken into consideration have normalized parameters d(H···O) ≤ 270 pm and θ(C - H···O) ≥ 115°.