Xue-Mei Zhao

Ni(II)-Catalyzed C(sp2)–H Alkynylation/Annulation with Terminal Alkynes under an Oxygen Atmosphere: A One-Pot Approach to 3-Methyleneisoindolin-1-one

A nickel(II)-catalyzed alkynylation/annulation cascade via double C-H cleavage has been successfully achieved. This methodology adopted a removable N,O-bidentate directing group with a broad range of amide substrates and terminal alkynes being well tolerated. The catalytic system allowed for atom-economical and environmentally benign one-pot construction of the corresponding 3-methyleneisoindolin-1-one derivatives using O2 as the external oxidant.

Reactivity of p-Toluenesulfonylmethyl Isocyanide: Iron-Involved C-H Tosylmethylation of Imidazopyridines in Nontoxic Media.

A novel iron-involved tosylmethylation of imidazo[1,2-α]pyridines with p-toluenesulfonylmethyl isocyanide in a solvent mixture of H2O and PEG400 under an Ar atmosphere has been developed. This protocol provides a facile synthetic route for the functionalization of the imidazo[1,2-α]pyridine scaffold with broad substrate compatibility, which is less expensive and environmentally friendly. The current methodology could further enable regioselective C-H tosylmethylation of indole at the C3 position. Also, p-toluenesulfonylmethyl isocyanide was utilized as the tosylmethylating reagent for the first time.

Catalyst-free Friedel–Crafts hydroxyalkylation of imidazo[1,2-α]pyridines with ethyl trifluoropyruvate

A catalyst free Friedel–Crafts (F–C) hydroxyalkylation of imidazo[1,2-α]pyridines with ethyl trifluoropyruvate is herein described using isopropyl ether as a solvent. Electron-donating and electron-withdrawing functional groups at various aromatic positions were well tolerated under our optimized conditions. The method enabled the generation of desired products in moderate to excellent yields under mild conditions, which makes this transformation an attractive, environmentally benign alternative for the synthesis of the target compounds.

Model of Evaluation on Quality of Graduates from Agricultural University Based on Factor Analysis

According to the factors of affecting the employment quality for the university graduates, we established the index system of evaluation on the employment quality for the university graduates. The factor analysis was used to establish the model for evaluating the employment quality for the university graduates. Several data sets were analyzed to illustrate the proposed method with the SPSS software. The results not only included the employment quality for the graduates from different colleges, but also included the employment quality for the graduates from different departments in one university. The results coincide with the statistical data about the employment on the official website. Some advice and countermeasures were given on the personnel training and the employment promotion to the universities and education authorities, which can provide the regulatory on employment quality and services of the graduate employment.

Synthesis, Characterization, and Crystal Structures of Heteroannular Cyclopalladated Ferrocenylimine-Pyridine Complexes

Two new heteroannular cyclopalladated ferrocenylimine-pyridine derivatives, 2a and 2b, were easily prepared by the reaction of chlorine-bridged binuclear palladium complexes, 1a and 1b, with pyridine in high yields. They were characterized by ESI-MS, H-NMR, and IR spectra. The detailed structures of complexes 2a and 2b were determined by single-crystal X-ray analysis. According to the crystal structure, the palladium atom is bound to the unsubstituted Cp ring, forming a new heteroannular pyridine-cyclopalladated large-membered metallocycle. Complex 2a exists as a dimer in the crystal due to intermolecular CH(CH˭N)···Cl hydrogen bonds, while 2b has a two-dimensional network structure formed by the intermolecular hydrogen bonds between the Cl atom with the adjacent C-H groups of Cp and pyridine.