Characterization of Reactive Intermediates in Palladium-Catalyzed Arylation of Methyl Acrylate(Heck Reaction)

1996 ◽  
Vol 35 (6) ◽  
pp. 657-659 ◽  
Author(s):  
John M. Brown ◽  
King Kuok(Mimi) Hii
Keyword(s):  
Methyl Acrylate ◽  
Heck Reaction ◽  
Reactive Intermediates ◽  
Palladium Catalyzed

Recent Developments in Heck-Type Reaction of Unactivated Alkenes and Alkyl Electrophiles

Synthesis ◽  
2020 ◽  
Author(s):  
Lili Shi ◽  
Junkai Fu ◽  
Shuangqiu Gao ◽  
Le Chang ◽  
Binglin Wang
Keyword(s):  
Heck Reaction ◽  
Alkyl Radicals ◽  
Type Reaction ◽  
The Past ◽  
Alkyl Electrophiles ◽  
Recent Developments ◽  
Palladium Catalyzed ◽  
Initial Work ◽  
Activated Olefins ◽  
Pseudo Halides

AbstractThe Mizoroki–Heck reaction is considered as one of the most ingenious and widely used methods for constructing C–C bonds. This reaction mainly focuses on activated olefins (styrenes, acrylates, or vinyl ethers) and aryl/vinyl (pseudo) halides. In comparison, the studies on unactivated alkenes and alkyl electrophiles are far less due to the low reactivity, poor selectivity, as well as competitive β-H elimination. In the past years, a growing interest has thus been devoted and significant breakthroughs have been achieved in the employment of unactivated alkenes and alkyl electrophiles as the reaction components, and this type of coupling is called as Heck-type or Heck-like reaction, which distinguishes from the traditional Heck reaction. Herein, we give a brief summary on Heck-type reaction between unactivated alkenes and alkyl electrophlies, covering its initial work, recent advancements, and mechanistic discussions.1 Introduction2 Intramolecular Heck-Type Reaction of Unactivated Alkenes and Alkyl Electrophiles2.1 Cobalt-Catalyzed Intramolecular Heck-Type Reaction2.2 Palladium-Catalyzed Intramolecular Heck-Type Reaction2.3 Nickel-Catalyzed Intramolecular Heck-Type Reaction2.4 Photocatalysis and Multimetallic Protocol for Intramolecular Heck-Type Reaction3 Intermolecular Heck-Type Reaction of Unactivated Alkenes and Alkyl Electrophiles3.1 Electrophilic Trifluoromethylating Reagent as Reaction Partners3.2 Alkyl Electrophiles as Reaction Partners4 Oxidative Heck-Type Reaction of Unactivated Alkenes and Alkyl Radicals5 Conclusions and Outlook

scholarly journals Fabrication and Characterization of Electrospun Poly(acrylonitrile-co-Methyl Acrylate)/Lignin Nanofibers: Effects of Lignin Type and Total Polymer Concentration

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 992
Author(s):  
Suchitha Devadas ◽  
Saja M. Nabat Al-Ajrash ◽  
Donald A. Klosterman ◽  
Kenya M. Crosson ◽  
Garry S. Crosson ◽  
...  
Keyword(s):  
Methyl Acrylate ◽  
Lignin Content ◽  
Polymer Concentration ◽  
Weight Ratio ◽  
Electrospun Nanofibers ◽  
Polymer Content ◽  
Blend Ratio ◽  
Blend Ratios ◽  
Poly Acrylonitrile

Lignin macromolecules are potential precursor materials for producing electrospun nanofibers for composite applications. However, little is known about the effect of lignin type and blend ratios with synthetic polymers. This study analyzed blends of poly(acrylonitrile-co-methyl acrylate) (PAN-MA) with two types of commercially available lignin, low sulfonate (LSL) and alkali, kraft lignin (AL), in DMF solvent. The electrospinning and polymer blend solution conditions were optimized to produce thermally stable, smooth lignin-based nanofibers with total polymer content of up to 20 wt % in solution and a 50/50 blend weight ratio. Microscopy studies revealed that AL blends possess good solubility, miscibility, and dispersibility compared to LSL blends. Despite the lignin content or type, rheological studies demonstrated that PAN-MA concentration in solution dictated the blend’s viscosity. Smooth electrospun nanofibers were fabricated using AL depending upon the total polymer content and blend ratio. AL’s addition to PAN-MA did not affect the glass transition or degradation temperatures of the nanofibers compared to neat PAN-MA. We confirmed the presence of each lignin type within PAN-MA nanofibers through infrared spectroscopy. PAN-MA/AL nanofibers possessed similar morphological and thermal properties as PAN-MA; thus, these lignin-based nanofibers can replace PAN in future applications, including production of carbon fibers and supercapacitors.

Mono- and Bidentate Phosphine Ligands in the Palladium-Catalyzed Methyl Acrylate Dimerization

2003 ◽  
Vol 345 (3) ◽  
pp. 402-409 ◽  
Author(s):  
Jörg Zimmermann ◽  
Igor Tkatchenko ◽  
Peter Wasserscheid
Keyword(s):  
Methyl Acrylate ◽  
Phosphine Ligands ◽  
Palladium Catalyzed ◽  
Bidentate Phosphine

Synthesis and Characterization of Novel Hyperbranched Polymers with Discrete Conjugated Units via Heck Reaction

1996 ◽  
Vol 28 (12) ◽  
pp. 1071-1076 ◽  
Author(s):  
Lioudmila Fomina ◽  
Sergei Fomine ◽  
Roberto Salcedo ◽  
Takeshi Ogawa
Keyword(s):  
Heck Reaction ◽  
Hyperbranched Polymers ◽  
Synthesis And Characterization

Palladium-Catalyzed Olefinations of Aryl Halides (Heck Reaction) and Related Transformations

ChemInform ◽  
2005 ◽  
Vol 36 (44) ◽  
Author(s):  
Matthias Beller ◽  
Alexander Zapf ◽  
Thomas H. Riermeier
Keyword(s):  
Heck Reaction ◽  
Aryl Halides ◽  
Palladium Catalyzed

scholarly journals Continuous-flow Heck synthesis of 4-methoxybiphenyl and methyl 4-methoxycinnamate in supercritical carbon dioxide expanded solvent solutions

2013 ◽  
Vol 9 ◽  
pp. 2886-2897 ◽  
Author(s):  
Phei Li Lau ◽  
Ray W K Allen ◽  
Peter Styring
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Methyl Acrylate ◽  
Heck Reaction ◽  
Continuous Flow ◽  
Flow Reactor ◽  
Product Distribution ◽  
Internal Diameter ◽  
Palladium Metal ◽  
Supercritical Carbon

The palladium metal catalysed Heck reaction of 4-iodoanisole with styrene or methyl acrylate has been studied in a continuous plug flow reactor (PFR) using supercritical carbon dioxide (scCO2) as the solvent, with THF and methanol as modifiers. The catalyst was 2% palladium on silica and the base was diisopropylethylamine due to its solubility in the reaction solvent. No phosphine co-catalysts were used so the work-up procedure was simplified and the green credentials of the reaction were enhanced. The reactions were studied as a function of temperature, pressure and flow rate and in the case of the reaction with styrene compared against a standard, stirred autoclave reaction. Conversion was determined and, in the case of the reaction with styrene, the isomeric product distribution was monitored by GC. In the case of the reaction with methyl acrylate the reactor was scaled from a 1.0 mm to 3.9 mm internal diameter and the conversion and turnover frequency determined. The results show that the Heck reaction can be effectively performed in scCO2 under continuous flow conditions with a palladium metal, phosphine-free catalyst, but care must be taken when selecting the reaction temperature in order to ensure the appropriate isomer distribution is achieved. Higher reaction temperatures were found to enhance formation of the branched terminal alkene isomer as opposed to the linear trans-isomer.

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