5459-40-5Relevant articles and documents
Fast and Regioselective Polymerization of para-Alkoxystyrene by Palladium Catalysts for Precision Production of High-Molecular-Weight Polystyrene Derivatives
Liao, Guangfu,Xiao, Zefan,Chen, Xiaolin,Du, Cheng,Zhong, Liu,Cheung, Chi Shing,Gao, Haiyang
, p. 256 - 266 (2020/01/09)
Polymerization of polar vinyl monomers by a coordination-insertion approach is a topic of fundamental importance to the field of polymer synthesis. Herein, we initially report the coordination-insertion polymerization of para-alkoxystyrene (pAOS) monomers by the dibenzobarrelene-based α-diimine palladium catalysts. The unprecedented polymerization characteristics including rapid initiation, fast chain growth, controlled chain transfer, and high-molecular-weight polymer with a narrow distribution (Mw > 1000 kg/mol, PDI 1.32) reflected previously unrecognized aspects of palladium-catalyzed pAOS polymerization. Chain-end analysis and characterization of palladium intermediates showed that the pAOS monomer was rapidly inserted into the primary palladium species in a full 1,2-regioselectivity, and the chain transfer took place by monomer-assisted β-H abstraction at high monomer concentrations. The resultant polymers showed improved mechanical properties and thermal stabilities and were also attractive candidates of hydrophilic styrenic resin.
Electrooxidative 1,2-Bromoesterification of Alkenes with Acids and N-Bromosuccinimide
Wan, Chao,Song, Ren-Jie,Li, Jin-Heng
supporting information, p. 2800 - 2803 (2019/04/30)
A simple three-component 1,2-bromoesterification of alkenes with acids and N-bromosuccinimide under electrochemical oxidative conditions is described. This transformation enables the construction of β-bromoalkyl esters via oxidative C-Br/C-O difunctionalization, where a variety of alkenes, including styrenes and cycloolefins, were well tolerated to react efficiently with a wide range of acids, such as aromatic acids, aliphatic acids, and amino acids.
Flow Chemistry Syntheses of Styrenes, Unsymmetrical Stilbenes and Branched Aldehydes
Bourne, Samuel L.,O'Brien, Matthew,Kasinathan, Sivarajan,Koos, Peter,Tolstoy, Paeivi,Hu, Dennis X.,Bates, Roderick W.,Martin, Benjamin,Schenkel, Berthold,Ley, Steven V.
, p. 159 - 172 (2013/03/13)
Two tandem flow chemistry processes have been developed. A single palladium-catalysed Heck reaction with ethylene gas provides an efficient synthesis for functionalised styrenes. Through further elaboration the catalyst becomes multi-functional and performs a second Heck reaction providing a single continuous process for the synthesis of unsymmetrical stilbenes. In addition, the continuous, rhodium-catalysed, hydroformylation of styrene derivatives with syngas affords branched aldehydes with good selectivity. Incorporation of an in-line aqueous wash and liquid-liquid separation allowed for the ethylene Heck reaction to be telescoped into the hydroformylation step such that a single flow synthesis of branched aldehydes directly from aryl iodides was achieved. The tube-in-tube semi-permeable membrane-based gas reactor and liquid-liquid separator both play an essential role in enabling these telescoped flow processes.
