Flexible Semicrown Ether‐Linked Symmetric Cationic Gemini Surfactants: Synthesis and Evaluation as Catalysts for Acceleration of Diastereoselective [3 + 2] Cycloaddition Reaction in Reversed Phase Micellar Media
Novel cationicgeminisurfactants with a hydrophilic oligo‐oxyethylene spacer group were synthesized and their physicochemical properties were identified. Computational studies for these compounds were also performed; molecular geometry, frontier molecular orbitals, and quantum chemical parameters were calculated using density functional theory (DFT). After exploration for catalytic activity, it was
Synthesis and Surface Characterization Studies of Polyether-Linked Symmetric Higher Sulfanyl-1,3,4-Oxadiazoles
作者:A. Yıldırım、S. Öztürk
DOI:10.1080/10426507.2014.999067
日期:2015.9.2
The synthesis and the characterization of a series of novel symmetric double length alkyl-chained sulfanyl-1,3,4-oxadiazoles functionalized with a polyether head group are reported. In addition, surface characterization studies were conducted on the metal surface of these synthesized compounds. The metal surfaces were characterized by contact angle measurements via the sessile-drop method, and 3D images of the metal surface were obtained using an optical profilometer. The surface studies showed that the inhibitor molecule increases the hydrophobic character and decreases the wettability of the metal surface.
Molecular Receptors for Adenine and Guanine Employing Metal Coordination, Hydrogen-Bonding and π-Stacking Interactions
作者:James E. Kickham、Stephen J. Loeb、Shannon L. Murphy
DOI:10.1002/chem.19970030807
日期:1997.8
AbstractThiacyclophane ligands 1 and 2, containing a meta‐xylyldithiaether unit, an aromatic spacing unit and a polyether chain, were prepared in good yield in a three‐step synthesis. The macrocyclic organopalladium complexes [Pd(L)‐(MeCN)][BF4] (3: L = 1; 4: L = 2) were prepared through palladation of the respective thiacyclophane ligand by reaction with [Pd(MeCN)4][BF4]2. These complexes act as metalloreceptors to aromatic amines such as p‐aminopyridine (pap), m‐aminopyridine (map) and the DNA nucleobases adenine and guanine. Binding occurs through simultaneous first‐ and second‐sphere coordination. This involves three separate interactions: first‐sphere σ donation from an aromatic N atom to the Pd centre, second‐sphere hydrogen bonds between the NH2 group and polyether O atoms, and π stacking between the electron‐poor aromatic rings of the substrate and the electron‐rich aromatic spacing units of the receptor. 1H NMR spectra exhibit chemical shift changes indicative of the H‐bonding and π‐stacking interactions in solution. X‐ray structures for thiacyclophane 1, metalloreceptor [Pd(1)(MeCN)][BF4] (3), metalloreceptor/model substrate complexes [Pd(1)(pap)][BF4 (5) and [Pd(2)‐(pap)][BF4] (7), and metalloreceptor/nucleobase complexes [Pd(1)(adenine)][BF4] (13), [Pd(2)(adenine)][BF4] (14) and [Pd(1)(guanine‐BF3)][BF4] (15b) show details of these interactions in the solid state.