Jianwei Xie

2-Pyrrolecarbaldiminato–Cu(II) complex catalyzed three-component 1,3-dipolar cycloaddition for 1,4-disubstituted 1,2,3-triazoles synthesis in water at room temperature

2-Pyrrolecarbaldiminato–Cu(II) complexes were established as efficient catalysts for the three-component 1,3-dipolar cycloaddition reaction of benzyl halides and sodium azide with terminal alkynes in water at room temperature, and several regioselective 1,4-disubstituted 1,2,3-triazoles have been synthesized under the reaction conditions in 55–97% yields.

A simple and efficient synthesis of 9-arylfluorenes via metal-free reductive coupling of arylboronic acids and N-tosylhydrazones in situ

A general, yet efficient synthesis method of 9-arylfluorenes via metal-free reductive coupling of N-tosylhydrazones and arylboronic acids has been developed. This methodology is realized by a one-pot protocol in two steps involving the preparation of N-tosylhydrazones by reacting tosylhydrazide with 9-fluorenone derivatives, followed by the reductive coupling of arylboronic acid in the presence of potassium carbonate to afford various 9-arylfluorenes analogues in moderate to excellent yields. Importantly, the catalytic system presented here enables the use of easily accessible starting materials and can be employed on a wide variety of substrates with good functional group tolerance. This protocol could also be particularly useful for the synthesis of 9-fluorenyl-substituted carbazolyl compounds.

Efficient and recyclable copper-based MOF-catalyzed N-arylation of N-containing heterocycles with aryliodides

Copper-based MOF-199 was used as an efficient heterogeneous catalyst to catalyze cross-coupling reactions between N-containing heterocycles and aryliodides with high yields. The catalyst can be easily separated from the reaction mixture, and can be reused at least 5 times without significantly decreasing the activity. The XRD results showed that the crystallinity and structure of MOF-199 can be maintained well during the coupling reaction.

Salen–Cu(II) complex catalysed N-arylation of pyrazole under mild conditions

Three inexpensive and air-/moisture-stable complexes (Salden)Cu (Salden = N, N’-bis(salicylidene)-1,2-dimethylethylenediamine), (Saldch)Cu (Saldch = N, N’-bis(salicylidene)-1,2-cyclohexenediamine), and (Salph)Cu (salph = N, N’-bis(salicylidene)-1,2-phenylenediamine) were synthesised and evaluated as catalysts for the N-arylation of pyrazole with aryl halides. A variety of aryl iodides and bromides underwent coupling with pyrazole, promoted by the (Saldch)Cu complex, in moderate to excellent yields without the protection by an inert gas.

Two new cucurbitane-type triterpenoid saponins isolated from ethyl acetate extract of Citrullus colocynthis fruit

Two new cucurbitacins I (1 and 2), together with eight known compounds (3–10), were isolated from the ethyl acetate extract of the fruit of Citrullus colocynthis. Compounds 3, 5–9 were isolated from C. colocynthis for the first time. The structures of new compounds were determined primarily from IR, HR-MS, 1D-, and 2D-NMR analysis.

Copper-catalysed N -arylation of pyrrole with aryl iodides under ligand-free conditions

A simple, inexpensive and ligand-free copper-catalysed N-arylation of pyrrole with aryl iodides has been developed giving N-arylated products in moderate to excellent yields. The catalyst loading is relative low (5 mol%) and the catalyst system was stable in air.

Efficient synthesis of 3-substituted indoles via a base-free copper-catalysed three-component reaction in water

The preparation of sixteen 3-substituted indoles in good to excellent yields under environmentally friendly conditions has been achieved via a three-component reaction in water of an indole, an aldehyde and malononitrile (or ethyl 2-cyanoacetate) catalysed by 5 mol% of 2-pyrrolecarbaldiminato-Cu(II).

Water-soluble (salicyladimine)2Cu complex as an efficient and renewable catalyst for Michael addition of indoles to nitroolefins in water

ABSTRACT An efficient and environmentally friendly protocol has been demonstrated for water-soluble (salicyladimine)2Cu complex-catalyzed Michael addition of indoles to nitroolefins in water at 30 °C. A variety of substituted indoles and β-nitrostyrenes could be worked well to provide the title products in 81–97% yields. Moreover, the catalyst can be reused directly at least for four times without significantly decreasing activity. GRAPHICAL ABSTRACT

Cu2O/Cs2CO3/DMF: An efficient catalytic system for N-arylation of imidazole with aryl halides under ligand-free conditions

ABSTRACT A ligand-free Cu-catalyzed protocol for the Ullmann-type N-arylation of N-containing heterocycles with aryl or heteroaryl iodides and bromides has been established. A broad range of functional groups is well tolerated on both of the cross-coupling partners, producing the desired products in good to excellent yields. GRAPHICAL ABSTRACT