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N-benzylcinchonidinium bromide, C26H29N2O+.Br-, with the systematic name (R)-[(2S,4S,5R)-1-benzyl-5-ethenyl-1-azoniabicyclo[2.2.2]octan-2-yl](quinolin-4-yl)methanol bromide, is a quaternary ammonium salt of the cinchona alkaloid cinchonidine. This salt is widely used as a chiral phase-transfer catalyst and chiral resolution agent. Both classical and non-classical hydrogen-bonding interactions, as well as anion effects have been shown to play key mechanistic roles in the catalysis of cinchona alkaloids. In an effort to understand the effects of water on these intermolecular interactions, the structures of anhydrous Nbenzylcinchonidinium bromide, (I), and the sesquihydrate, C26H29N2O+.Br-.-1.5H2O, (II), were determined. [ABSTRACT FROM AUTHOR]

A new chloranilate compound with 1-(2-fluorophenyl)piperazine has been synthesized and characterized using spectroscopic methods and X-ray diffraction. The atomic arrangement can be described by an H-bonded 3D network, formed by anionic entities, organic cations and H 2 O molecules linked together via N H…O, O H…Cl, C H…Cl and C H…O hydrogen bonds. The vibrational absorption bands of the various characteristic groups of this compound have been identified by infrared spectroscopy. Moreover, the thermal and dielectric analyses have shown that the title compound has a phase transition at 393 K. The surface mapped over the d norm property, highlights the A⋯H (A O, C, Cl and F) as the main intermolecular contacts. On the other hand, the geometry, intermolecular bonds and harmonic vibrational frequencies of the title molecule have been investigated using the B3LYP/6-31G (d, p) method. The stability of the structure obtained, as well as the charge transfer within the molecule, have been confirmed by determining the energies of the HOMO and LUMO levels and the theoretical gap energy. Molecular docking studies of the title compound have also been conducted as part of this study. [ABSTRACT FROM AUTHOR]

The title compound, C6H4BrNS, crystallizes in the space group P21/n with one complete molecule in the asymmetric unit. The non-H atoms are nearly planar (r.m.s for non-H atoms = 0.071 Å), with the nitrile group oriented antiperiplanar with respect to the thiophene S atom. Intermolecular Type I centrosymmetric Br. Br halogen interactions are present at a distance of 3.582 (1) Å and with a C--Br. . .Br angle of 140.7 (1)°. Additional weaker C--H. . .N, C--H... S, and S... π interactions are also present. A Hirshfeld analysis indicates Br... πBr interactions comprise only 1.9% of all the interatomic contacts. [ABSTRACT FROM AUTHOR]

The new compound 1-(2-methoxyphenyl)piperazinium chloranilate (MPP.CA) was synthesized and studied by the single crystal X-ray diffraction method. Its structure was confirmed by infrared spectroscopy. The crystal structure consists of ribbons of chloranilate anions and 1-(2-methoxyphenyl)piperazinium cations linked together by NH…O hydrogen bonds. Two protons are transferred from a chloranilic acid molecule to the nitrogen of the piperazine in this structure. Measurements of AC conductivity as a function of frequency at different temperatures indicated the hopping conduction mechanism; in addition, the variation of dielectric constant as a function ofTconfirmed the transition phase indicated by the differential scanning calorimetry (DSC). The physico-chemical properties, UV-Vis, DSC and dielectric properties are described. Hirshfeld surface analyzes all the intermolecular interactions involved within the structure, which are important to stabilize the structure. [ABSTRACT FROM AUTHOR]

A new synthesis of RuII(bpy)(sal)2 (1) (bpy=2,2′-bipyridyl, sal=salicylaldehyde) has been developed and the separation and characterization of all three geometric isomers have been completed. The isomers are denoted 1a (phenolic oxygens trans), 1b, (aldehyde oxygens trans), and 1c (aldehyde oxygen trans to phenolic oxygen). All three isomers have been characterized by 1H NMR, high resolution FAB-MS, UV–Vis, and cyclic voltammetry. Additionally, 1a has been characterized by solid-state UV–Vis and a single-crystal X-ray structural study. The solid-state packing of the RuII(bpy)(sal)2 molecules in the structure of 1a displays intermolecular π–π interactions between bpy ligands of adjacent molecules. The bpy interactions form infinite π-stacks with alternating short stacking distances of 3.437 and 3.402 Å. Synthesis, separation, and characterization of all three geometric isomers of RuII(bpy)(sal)2 (bpy=2,2′-bipyridyl, sal=salicylaldehyde) was completed. An X-ray structure of one isomer displays short intermolecular π–π interactions (3.437 and 3.402 Å). [Copyright &y& Elsevier]

Monoanionic N 2 P 2 beta-diketiminate (BDI) ligands with phosphine pendant arms were prepared and metallated with zinc(II) iodide. With a goal of understanding the ligands' sterics, methyl and methoyx substituents were introduced on the phenyl linkers. Two different binding modes were observed based on the presence of a substituent at position 6. [Display omitted] Monoanionic mixed N 2 P 2 donor beta-diketiminate (BDI) ligands with phosphine pendant arms, 2-(4-tolyl)-bis(2-diisopropylphosphinophenyl)propenediimine (abbreviated as Tol-BDI(DIPPP)2H), were prepared and metallated with zinc(II) iodide. Three ligand variations have been synthesized by incorporating different substituents (methyl or methoxy) on the linker phenyl rings at positions 4 and 6. In the 4-methyl zinc complex [Tol-BDI(DIPPMeP)2ZnI] and 4-methoxy zinc complex [Tol-BDI(DIPPMeOP)2ZnI], the metal is bound to all four donors on the ligand, rendering a distorted square pyramidal geometry around the zinc metal with τ 5 values of 0.25 and 0.29, respectively. However, the crystal structure of the 4,6-dimethyl zinc complex [Tol-BDI(DIPPMe2P)2ZnI] shows a four-coordinate zinc with only one phosphine bound to the metal, resulting in a distorted seesaw geometry around the metal. While X-ray crystallography shows no interactions between the metal center and the unbound phosphine, solution characterization reveals a symmetrical complex with both phosphines bound to the metal center in all three zinc complexes. [ABSTRACT FROM AUTHOR]

Advanced precursors to novel ferrocene-based ligands Cp 2 FeC(O)CH(R)C(O)CH 3 (R = benzyl, allyl) were synthesized from 1-ferrocenylbutane-1,3-dione via active methylene chemistry. Crystal structures were obtained and computational studies carried out to explore the structural features of these new compounds. Addition of carbonyl electrophiles resulted in the formation of unexpected products, which were identified and mechanisms for their formation proposed. [ABSTRACT FROM AUTHOR]