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An efficient sodium hydrogen sulfate catalyzed alkylation of indoles or amines with tertiary enamides has been accomplished in water, affording the pharmacologically and biologically active 2-oxo-1-pyrrolidine derivatives in moderate to excellent yields. The key to our success is the use of NaHSO4 as a low loading, inexpensive, green and recyclable catalyst and the reactions could be scaled up to gram level.

The first investigation into two C[double bond, length as m-dash]O bonds of CO2 reacting in one reaction through dual 1,3-dipolar cycloaddition of CO2 with isocyanides and dialkyl acetylenedicarboxylates has been reported. The reaction proceeded efficiently at 80 °C at a pressure of 1 atm of CO2, affording symmetric 1,6-dioxospiro[4,4]nonane-3,8-diene derivatives in moderate yields.

A one-pot indium trichloride-catalyzed indium-mediated allylation of dihydropyrans and dihyfrofurans has been found to be feasible. This catalytic system afforded the allylated diols in moderate to high yields.

α-functionalization of ferrocenyl alcohols by direct C–O bond activation by indoles, active methylene compounds, electron-rich arenes, anilines, alcohols, and thiols in acetic acid is described. This protocol provides a relatively green and efficient combinatorial access to ferrocene derivatives in a metal-free manner.

Direct alkylation of indoles and amines by tertiary enamides for the synthesis of pharmaceutically active 2-oxo-1-pyrrolidine analogues was described. With only a 0.5 mol% catalyst loading, molecular iodine was demonstrated to be efficiently enough to promote the reaction under neat condition. Only Markovnikov addition product was obtained indicating that the reactions proceeded with excellent regioselectivity.

A series of newly-developed bipolar triphenylamine benzimidazole derivatives, containing both hole-transporting and electron-transporting moieties, have been completely characterized by 1H and 13C NMR and HRMS, as well as their thermal, optical, and electrochemical properties. The results indicate that these compounds exhibit high fluorescence quantum yields, desirable HOMO levels and high thermal stabilities. Quantum chemical calculations were used to obtain the optimized ground-state geometries, spatial distributions of the HOMO, and the LUMO levels of these compounds. The agreement between experimental and calculated data suggests such compounds may have potential applications in organic light emitting diodes materials.

A series of the novel ‘ethyne-linked’ compounds containing carbazole and 1,8-naphthalimide groups have been synthesized by Pd/Cu-catalyzed Sonogashira reaction. These compounds were fully characterized by means of Fourier-transform IR, 1H, 13C NMR, and high resolution mass spectroscopy. The thermal, optical, and electrochemical properties were also investigated. As we expected, the results indicated that these compounds could improve charge-transport ability and fluorescent quantum yield by introducing the electron-transporting emitting moieties naphthalimide and the alkyne group to carbazole moieties.

A practical and efficient method for the synthesis of optically active O-acetyl cyanohydrins via one-pot lipase-catalyzed kinetic resolution of the in situ generated racemic cyanohydrins or O-acetyl cyanohydrins using an ionic liquid as both reaction media and promoter has been described.

A versatile method for the preparation of 2-aryl-2H-indazoles was developed by copper(I)-catalyzed intramolecular amination reaction under the conditions of [CuI/Cs 2 CO 3 (250 mol%)/l,4-dioxane/105 °C] starting from N'-aryl-N'-(o-bromobenzyl)acetylhydrazines. The method was applied to a wide scope of substrates and afforded indazole products in high yields.

In the presence of 20 mol% of chiral catalytic complex prepared from In(OTf)3 and chiral PYBOX, allyltributylstannane reacted with achiral ketones to afford the corresponding homoallylic alcohols in moderate to high enantioselectivities (54–95% ee), which constitutes the first example of enantioselective allylation of ketones catalyzed by the chiral In(III)-PYBOX complex.

Reactions of isatins with 5-aminopyrazole afforded the 3-(5-aminopyrazol-4-yl)-3-hydroxy-2-oxindolines in good to excellent yields in refluxing water. No catalysts were required in the process. The new method exhibited the characteristics including green process, high yields, easy operation, and mild reaction conditions.

Nucleophilic substitution of ferrocenyl alcohols with various aliphatic alcohols in the presence of a catalytic amount of ytterbium triflate [Yb(OTf)3] was studied. It was found the unsymmetrical ferrocenyl ethers could be easily obtained in excellent yields when the reactions were performed in primary and secondary alcohols. However, in other organic non-alcoholic solvents such as acetonitrile, the formation of symmetrical ferrocenyl ethers rather than unsymmetrical ones was observed.