ChemInform Abstract: An Unexpected Bromolactamization of Olefinic Amides Using a Three-Component Co-Catalyst System.

ChemInform ◽  
2016 ◽  
Vol 47 (23) ◽  
Author(s):  
Yi An Cheng ◽  
Wesley Zongrong Yu ◽  
Ying-Yeung Yeung
Keyword(s):  
Tetrahedron ◽  
2021 ◽  
pp. 132412
Author(s):  
Satavisha Kayal ◽  
Jun Kikuchi ◽  
Naoya Shinagawa ◽  
Shigenobu Umemiya ◽  
Masahiro Terada

2012 ◽  
Vol 217-218 ◽  
pp. 366-373 ◽  
Author(s):  
Guowen Wang ◽  
Dong Wang ◽  
Xiaochen Xu ◽  
Lifen Liu ◽  
Fenglin Yang

2020 ◽  
Vol 268 ◽  
pp. 118466 ◽  
Author(s):  
Xiaoyi Hu ◽  
Xiangkang Zeng ◽  
Yue Liu ◽  
Jun Lu ◽  
Shi Yuan ◽  
...  

1966 ◽  
Vol 39 (3) ◽  
pp. 508-520 ◽  
Author(s):  
Morris Gippin

Abstract The requirement of water or oxygen to activate the diethylaluminum chloride co-catalyst used with a cobalt compound to produce 98 per cent cis-1,4 poly-butadiene was reported previously. Activation is considered to form two alkylaluminum compounds differing in Lewis acidity. Several reactions presumed to lead to the formation of the higher acid were carried out with a minor proportion of the diethylaluminum chloride by partial dealkylation with organic hydroperoxide, halogen, tertiary alcohol, organic halide or aluminum. Water is neither necessary nor desirable in the ethylaluminum sesquichloride-cobalt octoate catalyst system. Polar solvents do not appreciably alter the cis-1,4 catalysis with diethylaluminum chloride/water/cobalt octoate, but do decrease the rate or extent of polymerization with increasing dielectric constant of the solvent. A mechanism of cobalt catalysis of butadiene polymerization is proposed.


2016 ◽  
Vol 49 (5) ◽  
pp. 408-421 ◽  
Author(s):  
Jieting Geng ◽  
Youguo Shao ◽  
Feng Song ◽  
Feng Li ◽  
Jing Hua

Coordination polymerization of styrene (St) using molybdenum pentachloride supported by phosphite ligand in the presence of metal organic compound was studied for the first time. The types of phosphite and co-catalysts significantly affected the catalytic activity of the molybdenum (V) (Mo(V)) active center and the number-average molecular weight ( Mn) of the resultant polymer. Among the examined catalysts, tri(nonylphenyl)phosphite (TNPP) ligand and AlOPhCH3( i-Bu)2 as co-catalyst provided the polymer with highest yield (up to 87.1%), metallocene as co-catalyst provided the polymer with highest Mn (up to 5.32 × 105). The effect of [P]/[Mo] molar ratio on catalyst activity of the polymerization was discussed and the structures of Mo·TNPP complexes were preliminarily studied by infrared (IR) and ultraviolet spectroscopies. Besides, the polystyrene (PS) samples synthesized through bulk polymerization and solution polymerization were characterized by gel permeation chromatography, IR, carbon 13 nuclear magnetic resonance, and differential scanning calorimetry, respectively, and the results indicated both of the PS had high molecular weight (approximately 105) and atactic structure. All these results demonstrated that Mo(V) catalyst system was very effective for St polymerization.


2014 ◽  
Vol 50 (23) ◽  
pp. 3052-3054 ◽  
Author(s):  
Thomas J. Williams ◽  
Alan J. Reay ◽  
Adrian C. Whitwood ◽  
Ian J. S. Fairlamb

The C2-arylation of tryptophan derivatives, and small peptides containing tryptophan, is possible using a Pd/Cu co-catalyst system. The products are highly fluorescent, with potential for studying protein function.


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