Jinwei Yuan

nBu4NI-catalyzed direct synthesis of α-ketoamides from aryl methyl ketones with dialkylformamides in water using TBHP as oxidant.

A novel and easy practical direct synthesis of α-ketoamides has been developed without metals in water. This procedure was catalyzed by nBu(4)NI using TBHP as oxidant from simple substrates, aryl methyl ketones and dialkylformamides.

Silver catalyzed decarboxylative direct C2-alkylation of benzothiazoles with carboxylic acids

A novel and efficient silver catalyzed decarboxylative direct C2-alkylation of benzothiazoles with carboxylic acids for the synthesis of 2-alkyl benzothiazoles was developed.

Cu/Ag-catalyzed double decarboxylative cross-coupling reaction between cinnamic acids and aliphatic acids in aqueous solution

A novel double decarboxylative cross-coupling catalyzed by copper and silver has been developed. This method provides a practical approach for the flexible synthesis of alkenes and alkynes from the readily affordable substrates.

Ultrasonic-assisted synthesis of chrysin derivatives linked with 1,2,3-triazoles by 1,3-dipolar cycloaddition reaction.

The 1,3-dipolar cycloaddition reaction between 7-(3-azidopropoxy)-5-hydroxyflavone and phenylacetylene was carried out to investigate the synthesis of 7-(3-(4-phenyl-1,2,3-triazol-1-yl)propoxy)- 5-hydroxyflavone in presence of ultrasound (sono-synthesis) and absence of ultrasound (conventional method) under relatively optimized solvent and catalyst conditions. The reaction rate was notably accelerated with the help of ultrasound irradiation. An experiment was especially carried out for investigating the acceleration mechanism of ultrasound on the cycloaddition. A novel series of chrysin derivatives linked with 1,2,3-triazoles were obtained by the copper(I)-catalyzed 1,3-dipolar Huisgen cycloaddition reaction using t-BuOH/H(2)O (1:1 v/v) as reaction solvents and CuSO(4)·5H(2)O/sodium ascorbate as the catalyst at room temperature in the presence of ultrasound irradiation. Their structures are elucidated by NMR, ESI MS, IR and Elemental analysis.

CuSO4 center dot 5H(2)O-catalyzed alkynylphosphonates formation - An efficient coupling reaction of terminal alkynes with H-phosphonates

National Natural Science Foundation of China [20972130, 21072178]; Innovation Specialist Projects of Henan Province [114200510023]; Technological Leading Projects of the Local Government of Zhengzhou [112PLJRC359]

Iron-catalyzed regioselective direct coupling of aromatic aldehydes with coumarins leading to 3-aroyl coumarins

An efficient protocol for iron-catalyzed cross-coupling of coumarins with aromatic aldehydes has been developed. The various 3-aroyl coumarins were selectively afforded in moderate yields. Some notable features of this protocol are high efficiency, wide functional group tolerance, and commercially available and cheap aromatic aldehydes and coumarins as starting materials. Furthermore, these reaction conditions were also applicable to N-methyl quinolinones, affording the corresponding 3-aroyl quinolinone derivatives in good yields.

NCN pincer palladium complexes based on 1,3-dipicolyl-3,4,5,6-tetrahydropyrimidin-2-ylidenes: synthesis, characterization and catalytic activities

The synthesis of novel pincer palladium complexes containing ring expanded six-membered N-heterocyclic carbenes (NHCs) via direct metallation of the precursors tetrahydropyrimidin-1-ium hexafluorophosphates in the presence of NaN(SiMe3)2 is presented. The structure has been characterized unambiguously by X-ray single crystal analysis. Catalytic activity investigation showed that the complexes catalyzed the Heck reaction of aryl bromides with acrylate/styrene efficiently when using Et3N as base and DMA as solvent.

Chelating palladium complexes containing pyridine/pyrimidine hydroxyalkyl di-functionalized N-heterocyclic carbenes: synthesis, structure, and catalytic activity towards C–H activation

The synthesis of novel chelating palladium complexes containing pyridine/pyrimidine hydroxyalkyl di-functionalized N-heterocyclic carbenes (NHCs) via direct metallation of the precursor imidazolium salts is presented. The structure has been characterized unambiguously by X-ray single crystal analysis. Catalytic activity investigation showed that the complexes catalyse the direct C–H bond arylation of (benzo)oxazoles efficiently when using tBuOLi as base and DMF as solvent.

AgNO3-catalyzed direct C–H arylation of quinolines by oxidative decarboxylation of aromatic carboxylic acids

An efficient silver-catalyzed intermolecular decarboxylative arylation of quinolines has been developed using cheap aromatic carboxylic acids as arylating reagents under microwave irradiation. The reaction demonstrates a broad substrate scope and excellent functional group tolerance. This method provided an effective and easy way to synthesize arylated quinoline derivatives. The radical trapping experiments showed that this process involved the radical mechanism.

Inclusion complexes of phosphorylated daidzein derivatives with β-cyclodextrin: Preparation and inclusion behavior study.

In the present work the feasibility of β-cyclodextrin in complexation was explored, as a tool for improving the solubility and biological ability of daidzein derivatives. A series of phosphorylated daidzein derivatives featuring different chain lengths were synthesized through a modified Atherton-Todd reaction and their inclusion complexes with βCD were prepared by coprecipitation method. The inclusion complexation behavior was studied by fluorescence, UV, FT-IR, MS and (1)H NMR. The results showed that only phosphorylated daidzein derivative carrying small substituent group ((C(2)H(5)O)(2)PO) entered the cavity of βCD and formed 1:1 inclusion complex. The formation constant was 175(mol/L)(-1).