Preparation of Surfactant Ruthenium Complexes Containing 6,6′-BIS(N-Alkylbenzimidazolyl)-2,2′-Bipyridine with Long Alkyl Chains

Abstract

&tractNew surfactant ruthenium complexes, [Ru(X)(Y)(L8 or 12)Jn+, were synthesized by the reaction of [R~CI~(q~-p-cymene)]~ with L8 or 12 in methanol or DMSO, where L8 or 12 stands for tetradentate 6,6'-bis(N-octyl-or lau~lbenzimidazolyl)-2,2'-bipyridine. The complexes formed stable monolayer films on the Langmuir trough at the air-water interface and were transferred to a glass plate. The K-A isotherms indicate the phase transition between expanded liquid state and the solid state at around 14 mNm-', and monolayer collapses at a pressure of 45 mNm-'. This phase transition may be interpreted in terms of a change of molecular orientation. The structure of the LB films on glass were discussed.

Characterization of Langmuir Monolayers of the Amphiphilic Ru Complex at the Air/Water Interface by Ultraviolet Photoelectron Yield Spectroscopy

“…The amphiphilic ruthenium complex, trans -RuCN 2 (C 12 -bpybim) (C 12 -bpybim = 6,6‘-bis( N -laurylbenzimidazoil)-2,2‘-bipyridine), shown in Chart , was synthesized by the reaction of [RuCl 2 (η 6 - p -cymene)] 2 with C 12 -bpybim in ethanol and the following metathesis with cyanide anion. The details of the synthesis of the complex are given elsewhere 1 Molecular Structure of the Amphiphilic Ruthenium Complex, trans -RuCN 2 (C 12 -bpybim) …”

“…The details of the synthesis of the complex are given elsewhere. 8 The surface pressure-area (π-A) isotherm was recorded on a computer-controlled LB transfer system (USI System Co. FSD-300P) at 20 °C. The surface pressure was monitored with filter paper during a constant rate compression.…”

“…The fabrication of a designed, ordered, and oriented molecular film by the Langmuir−Blodgett (LB) method has attracted recent interest . Ruthenium pyridyl complexes are suitable to be the binding blocks for the construction of molecular devices for electron transfer, energy transfer, and proton transfer using the LB method because they have redox-active and photoactive properties and catalytic activities. − We have studied the construction of the ordered multilayers organized by photoactive Ru pyridyl complexes and characterized the properties of the films. − It is well-known that, to control the two-dimensional structure of the LB film and to construct well-defined layered materials, it is important to characterize the Langmuir layer at the air/water interface in situ. Although a number of techniques have been applied to characterize the structure and the morphology of the transferred LB films on the solid substrates, spectroscopic methods, which can be applied to the analysis of the structure of Langmuir films at the air/water interface, are limited.…”

“…[2][3][4][5][6][7] We have studied the construction of the ordered multilayers organized by photoactive Ru pyridyl complexes and characterized the properties of the films. [8][9][10] It is well-known that, to control the two-dimensional structure of the LB film and to construct well-defined layered materials, it is important to characterize the Langmuir layer at the air/water interface in situ. Although a number of techniques have been applied to characterize the structure and the morphology of the transferred LB films on the solid substrates, spectroscopic methods, which can be applied to the analysis of the structure of Langmuir films at the air/water interface, are limited.…”

Fine-Tuning of the Optical and Electrochemical Properties of Ruthenium(II) Complexes with 2-Arylbenzimidazoles and 4,4′-Dimethoxycarbonyl-2,2′-bipyridine

“…The second type is C^N ligands ( Figure 1 b), where the Ru-C bond is formed with the imidazole fragment and one of the imidazole nitrogen is bonded to a pyridine [ 27 , 38 ]. The third type is the N^N ligands of the 2-benzimidazol-2-yl-pyridines class ( Figure 1 c) [ 27 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ]. The C^N ligands based on 2-arylimidazoles that interest us are presented in Figure 1 d [ 48 , 49 , 50 ].…”