Novel lactam-cation-based Brønsted acid ionic liquids (ILs) were prepared through a simple and atom-economic neutralization reaction between a lactam, such as caprolactam and butyrolactam, and a Brønsted acid, HX, where X is BF4-, CF3COO-, phCOO-, ClCH2COO-, NO3-, or H2PO4-. The density, viscosity, acidic scale, electrochemical window, temperature dependency of ionic conductivity, and thermal property of these ILs were measured and investigated in detail. The results show that protonated caprolactam tetrafluoroborate (CPBF) has a relatively strong acidity with -0.22 of Hammett acidic scale H0 and caprolactam trifluoroacetate (CPTFA) and pyrrolidonium trifluoroacetate (PYTFA) ILs possess very low viscosities, that is, 28 cP and 11 cP, respectively. An investigation of thermal property showed that a wide liquid range (up to -90 degrees C), moderate thermal stability (up to 249 degrees C for 10% of decomposition), and complex polymorphism were observed in these ILs. In comparison to imidazolium-cation-based ILs, the lactam-cation-based Brønsted acid ILs have a relatively lower cost, lower toxicity, and comparable ion conductivity and heat storage density (more than 200 MJ/m3). They have wide applicable perspectives for fuel cell devices, thermal transfer fluids, and acid-catalyzed reaction media and catalysts as replacements of conventional inorganic acids.

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Refined methyl, ethyl, propyl, 1-butyl, and 2-butyl biodiesels as well as unrefined methyl biodiesels containing glycerides were prepared, and their solvent power was evaluated by measuring the kauri-butanol value. By analysis of the kauri-butanol values of biodiesels with different fatty acid profiles and different alcohol types, some interesting results were obtained. The pure methyl esters have larger kauri-butanol values than those containing glycerides. The unsaturated fatty acid esters have larger kauri-butanol values than saturated fatty acid esters, while the number of double bonds of the unsaturated fatty acid has little effect on the value. The shorter the carbon chain of the fatty acid group or alcohol group, the larger the kauributanol value of biodiesel. Biodiesel with straight chains has a larger kauri-butanol value than that with branched chains.

ABSTRACT[RhCp*Cl 2 ] 2 can catalyze the oxidative coupling of N-aryl and N-alkyl benzamidines with alkynes to give N-substituted 1-aminoisoquinolines in high selectivity.Transition-metal catalyzed organic reactions via activation of CÀH bonds have attracted increasing attention. 1 This process is attractive in that CÀH bonds are ubiquitous and prefunctionalization of CÀH bonds is no longer necessary. Therefore, selective and efficient functionalization of CÀH bonds under mild conditions has been long sought, and this should allow the construction of complex molecules in an energy-efficient and step-economic fashion. Significant progresses have been made, and this topic has been extensively reviewed. 2 Among the various promising activation strategies is the utilization of a proximal directing group, which facilitates the activation of substrate ortho CÀH bonds. By utilizing this strategy with oxygen and nitrogen directing groups, rhodium complexes have stood out as efficient catalysts in the functionalization of CÀH bonds using unsaturated coupling partners. 3 Recently, Rh(III)-catalyzed oxidative CÀH functionalization of arenes with alkynes has been increasingly explored, which allowed for the synthesis of a broad spectrum of heterocycles. 4 A number of research groups, including ours, 5 have successfully applied this method to the synthesis of isoquinolines, 6 isoquinolones, 5c,7 indoles, 8 isocoumarins, 9 indenols, 4b,d pyrroles, 10 and pyridones. 5d,11 † The Chinese Academy of Sciences. ‡ Northwest Normal University.

A convenient method for the copper(I)-catalyzed arylation of substituted imidazo[1,2-a]pyridine has been developed. This method is applicable to a variety of aryl electrophiles, including bromides, iodides, and triflates. It represents the first general process for C-3 arylation of substituted imidazo[1,2-a]pyridine by Cu(I) catalysis to construct various functionalized imidazo[1,2-a]pyridine core π-systems.

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Put it on a ring: A rhodium(III) complex can catalyze the oxidative coupling of azomethine imines with olefins, leading to the synthesis of 1,2‐dihydrophthalazines, olefinated aldehydes, or fused pyridines, depending on the conditions used.

Rh(III)-catalyzed oxidative coupling reactions between isoquinolones with 3-aryl groups and activated olefins have been achieved using anhydrous Cu(OAc)(2) as an oxidant to give tetracyclic products. The nitrogen atom acts as a directing group to facilitate ortho C-H activation. This reaction can be one-pot starting from methyl benzohydroxamates, without the necessity of the isolation of isoquinolone products. A broad scope of substrates has been demonstrated, and both terminal and internal activated olefins can be applied. In the coupling of N-methylmaleimide, a Wacker-like mechanism was proposed, where backside attack of the NH group in isoquinolones is suggested as a key step. Selective C-H activation has also been achieved at the 8-position of 1-naphthol, leading to an olefination product.