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Ether groups are well-known for their unique contribution to low viscosity and high conductivity, and hence ether-functionalized ionic liquids (ILs) have been widely studied and successfully employed in various applications. However, the ether chain length effect on physicochemical properties is complex and still lacks a systematic study. In this study, an attempt was made to provide a thorough understanding for such complexities. A series of ILs functionalized with various ether groups (CmOCn-, n, m = 1, 2, or 3) were synthesized and characterized, and their properties with irregular variations along the ether chain length were recorded and systematically analyzed. Generally, the irregular variations are mediated by three interrelated factors: the Cm- tail length, the −Cn- spacer length, and hydrogen bonding interaction. For example, though ROC2- is bulkier by a CH2 unit than ROC1-, ROC2-based imidazolium ILs are less viscous and more conductive than ROC1--based analogues, since ROC1- is apt to form intermolecular rather than the five-membered-ring intramolecular hydrogen bonding with the imidazolium ring H atoms, while for ROC2- the six-membered-ring intramolecular hydrogen bonding comes into prominence. [ABSTRACT FROM AUTHOR]

A series of new ionic liquids, based on dialkoxy-functionalized quaternary ammonium cations {side chains: 1 = CH3, 1O1 = CH3OCH2, 1O2 = CH3OC2H4, 2O2 = C2H5OC2H4; cations: [N11,1O1,1O2], [N11,1O1,2O2], [N11,1O2,1O2], [N11,1O2,2O2] and [N11,2O2,2O2]}, with BF4−, (CF3SO2)2N−(NTf2) and CH3CO2−(OAc) as counteranions, have been prepared and characterized. Their basic properties, such as spectroscopic characteristics, melting point, glass transition temperature, thermal stability, electrochemical window, density, refractive index, viscosity and conductivity, were measured and comparatively studied. The incorporation of two flexible alkoxy chains makes the quaternary ammonium salts highly qualified to be low-viscous and high-conductive room temperature ILs, and even some of them have significantly better fluidity than the popular imidazolium ILs with a similar molecular weight, e.g.[N11,1O1,2O2]BF4(151 cP and 2.11 mS cm−1, Mw: 249) vs.[HMIm]BF4(220 cP and 1.2 mS cm−1, Mw: 256) at 25 °C. The electrochemical windows of these ILs were evaluated up to 5.5 V. In addition, the dialkoxy OAc ILs were found to have excellent solvent power for cellulose under mild conditions, e.g.a solution of 18 wt% microcrystalline cellulose in [N11,2O2,2O2]OAc at 80 °C. By precipitation with water, the dissolved cellulose (I crystal structure) was regenerated as nanosized cellulose II particles with increased surface area and decreased crystallinity, determined by FE-SEM and XRD. [ABSTRACT FROM AUTHOR]

A mild one-pot method for the direct conversion of aryl, heteroaryl and alkyl aldehydes into nitriles was achieved by forming the corresponding oximes in situ with NH2OH and allowing them to react with CuO and acetonitrile. Yields of the 13 nitriles prepared were moderate to very good (62-91%). [ABSTRACT FROM AUTHOR]

A simple method for the preparation of nitriles in moderate to good yield has been achieved by treatment of aromatic and heterocyclic aldoximes with malononitrile in water at reflux in the presence of copper acetate as catalyst. Arylaldoximes with an electron-donating group showed the highest reactivity, their conversion being achievable at room temperature. [ABSTRACT FROM AUTHOR]

Chemoselective hydrogenation of aromatic nitro compounds were first efficiently achieved over Au/Fe(OH)x at 100-120 °C for 1.5-6 h (depending on different substrates) in the presence of CO and H2O. [ABSTRACT FROM AUTHOR]

Chemoselective hydrogenation of aromatic nitro compounds were first efficiently achieved over Au/Fe(OH)xat 100–120 °C for 1.5–6 h (depending on different substrates) in the presence of CO and H2O. [ABSTRACT FROM AUTHOR]