Wednesday 14 May 2014

Comparing Catalysts










The selectivity of ligand-capped palladium catalysts in hydrogenation reactions is compared with their lead-poisoned equivalents
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Giant Vesicles from Sophorolipids










Sophorolipids based on linolenic acid self-assemble into giant-vesicle-type structures with membranes similar to those of cell walls
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Oxacycle Synthesis










New approach to synthesis of spirocyclic ethers, aryl ethers, and various oxacycles including oxetanes
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Making Mushroom Molecules









A synthetic route to prepare an unusual tricyclic fungal alkaloid has been developed
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Saturday 19 April 2014

A highly efficient approach to vanillin starting from 4-cresol




Green Chem., 2014, Advance Article
DOI: 10.1039/C4GC00003J, Paper
Jian-An Jiang, Cheng Chen, Ying Guo, Dao-Hua Liao, Xian-Dao Pan, Ya-Fei Ji
A highly efficient three-step approach to vanillin has been developed starting from 4-cresol.

A highly efficient approach to the famous flavor and fragrance compound vanillin has been developed starting from 4-cresol with the attention focused on improving the sustainability of all the reactions. The approach involves a three-step sequence of the quasi-quantitative selective clean oxybromination of 4-cresol, the high-yield selective aerobic oxidation of 2-bromo-4-cresol, and the quantitative methoxylation of 3-bromo-4-hydroxybenzaldehyde with the recovery of pure methanol. Herein, the pivotal oxidation and methoxylation reactions are logically investigated and developed into two concise methodologies. As a green alternative, the approach holds significant value for the sustainable manufacturing of vanillin.

Oxyhalogenation of thiols and disulfides into sulfonyl chlorides/bromides using oxone-KX (X = Cl or Br) in water




A simple and rapid method for efficient synthesis of sulfonyl chlorides/bromides by oxyhalogenation of thiols and disulfides with oxone-KX (X = Cl or Br) using water as the solvent is described.


Green Chem., 2014, Advance Article
DOI: 10.1039/C4GC00246F, Paper
Sridhar Madabhushi, Raveendra Jillella, Vinodkumar Sriramoju, Rajpal Singh
A simple and efficient method for synthesis of sulfonyl chlorides/bromides by oxyhalogenation of thiols and disulfides with oxone-KX (X = Cl or Br) using water as the solvent is presented



Sunday 16 March 2014

Aqueous-phase selective hydrogenation of phenol to cyclohexanone over soluble Pd nanoparticles

Aqueous-phase selective hydrogenation of phenol to cyclohexanone over soluble Pd nanoparticles

Green Chem., 2014, Advance Article
DOI: 10.1039/C3GC42408A, Paper
Jing-Fang Zhu, Guo-Hong Tao, Hang-Yu Liu, Ling He, Qian-Hui Sun, Hai-Chao Liu


Corresponding authors
a
College of Chemistry, Sichuan University, Chengdu 610064, China
b
College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
c
Kunming Sino-Platinum Metals Catalyst Co., Ltd., Kunming 650101, China

The water-soluble Pd nanoparticles are highly-efficient catalysts for the selective hydrogenation of phenol to cyclohexanone in water under mild conditions.


The water-soluble metal nanoparticles (NPs) stabilized by poly(N-vinyl-2-pyrrolidone) (PVP) were prepared and examined as catalysts for the one-step selective hydrogenation of phenol to cyclohexanone in water. More than 99% conversion of phenol and selectivity to cyclohexanone was obtained at 90 °C and 1 atm H2 for 16 h over “soluble” Pd NPs that were reduced by NaBH4and stabilized by PVP. These Pd NPs were stable, and no leaching or aggregation was detected after five successive runs, showing their advantage for catalyzing the efficient synthesis of cyclohexanone via the one-step selective hydrogenation of phenol under mild conditions.