100-80-1Relevant articles and documents
Excellent Selectivity with High Conversion in the Semihydrogenation of Alkynes using Palladium-Based Bimetallic Catalysts
Liu, Jian,Zhu, Yanan,Liu, Chang,Wang, Xiaoshi,Cao, Changyan,Song, Weiguo
, p. 4053 - 4057 (2017)
A series of active-carbon-supported PdPb and PdCu bimetal catalysts were prepared for the selective semihydrogenation of alkynes in the liquid phase. The Pd0.33Pb0.67/C catalyst showed the best performance for various alkynes under mild reaction conditions (room temperature and ambient H2 pressure) and achieved 100 % conversion with 98 % selectivity to alkenes. In particular, over-hydrogenation was avoided at complete alkyne conversion.
Homogeneous Unimolecular Pyrolysis Kinetics of o-, m-, and p-Methyl-2-phenylethyl Chlorides
Chuchani, Gabriel,Medina, Jose D.,Martin, Ignacio,Hernandez A, Jose A.
, p. 3900 - 3902 (1981)
The pyrolysis kinetics of isomeric methyl-2-phenylethyl chlorides have been studied in a static system over the pressure range of 56-240 torr and the temperature range of 419-470 deg C.These eliminations in seasoned vessels and in the presence of propene inhibitor are homogeneous and unimolecular, and follow a first-order rate law.The rate coefficients are given by the following Arrhenius equations: for 0-methyl-2-phenylethyl chloride, log k1 (s-1)=13.76+/-0.27)-(231.4+/-3.6) kJ mol-1 (2.303RT)-1; for m-methyl-2-phenylethyl chloride, log k1(s-1)=12.84+/-0.26)-(219.2+/-3.5) kJ mol-1 (2.303RT)-1; for p-methyl-2-phenylethyl chloride, log k1 (s-1)=(14.03+/-0.19)-(234.1+/-2.5) kJ mol-1 (2.303RT)-1.The electron release of the methyl substituent, at the three isomeric positions of the benzene ring, is very weak and does not reinforce the phenyl participation in rate enchancement relative to 2-phenylethyl chloride.
Tandem Diazotization Heck Reactions: A General Synthesis of Substituted Styrenes from Anilines
Beller, Matthias,Fischer, Hartmut,Kuehlein, Klaus
, p. 8773 - 8776 (1994)
The palladium-catalyzed olefination of different anilines with ethylene is shown to proceed generally in good yields.The substituted styrenes were obtained highly selective in a direct tandem diazotization Heck reaction at room temperature under atmospheric pressure of ethylene without concomitant side reaction to stilbenes.
Selective transfer semihydrogenation of alkynes with nanoporous gold catalysts
Wagh, Yogesh S.,Asao, Naoki
, p. 847 - 851 (2015)
A facile, highly chemo- and stereoselective transfer semihydrogenation of alkynes to Z-olefins has been achieved by use of unsupported nanoporous gold (AuNPore) as a heterogeneous catalyst together with formic acid as a hydrogen donor. A variety of terminal/internal and aromatic/aliphatic alkynes were reduced to the corresponding alkenes in high chemical yields with good functional-group tolerance. The catalyst is robust enough to be reused without leaching.
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Marvel et al.
, p. 736 (1946)
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Photoredox Catalyzed Sulfonylation of Multisubstituted Allenes with Ru(bpy)3Cl2 or Rhodamine B
Chen, Jingyun,Chen, Shufang,Jiang, Jun,Lu, Qianqian,Shi, Liyang,Xu, Zekun,Yimei, Zhao
supporting information, (2021/11/09)
A highly regio- and stereoselective sulfonylation of allenes was developed that provided direct access to α, β-substituted unsaturated sulfone. By means of visible-light photoredox catalysis, the free radicals produced by p-toluenesulfonic acid reacted with multisubstituted allenes to obtain Markovnikov-type vinyl sulfones with Ru(bpy)3Cl2 or Rhodamine B as photocatalyst. The yield of this reaction could reach up to 91%. A series of unsaturated sulfones would be used for further transformation to some valuable compounds.
Switchable Chemoselectivity of Reactive Intermediates Formation and Their Direct Use in A Flow Microreactor
Ashikari, Yosuke,Tamaki, Takashi,Kawaguchi, Tomoko,Furusawa, Mai,Yonekura, Yuya,Ishikawa, Susumu,Takahashi, Yusuke,Aizawa, Yoko,Nagaki, Aiichiro
supporting information, p. 16107 - 16111 (2021/10/12)
A chemoselectivity switchable microflow reaction was developed to generate reactive and unstable intermediates. The switchable chemoselectivity of this reaction enables a selection for one of two different intermediates, an aryllithium or a benzyl lithium, at will from the same starting material. Starting from bromo-substituted styrenes, the aryllithium intermediates were converted to the substituted styrenes, whereas the benzyl lithium intermediates were engaged in an anionic polymerization. These chemoselectivity-switchable reactions can be integrated to produce polymers that cannot be formed during typical polymerization reactions.
Electrochemistry enabled selective vicinal fluorosulfenylation and fluorosulfoxidation of alkenes
Jiang, Yimin,Shi, Zhaojiang,Wu, Jinnan,Wu, Shaofen,Ye, Keyin,Yu, Yi,Yuan, Yaofeng
supporting information, (2021/11/17)
Both sulfur and fluorine play important roles in organic synthesis, the life science, and materials science. The direct incorporation of these elements into organic scaffolds with precise control of the oxidation states of sulfur moieties is of great significance. Herein, we report the highly selective electrochemical vicinal fluorosulfenylation and fluorosulfoxidation reactions of alkenes, which were enabled by the unique ability of electrochemistry to dial in the potentials on demand. Preliminary mechanistic investigations revealed that the fluorosulfenylation reaction proceeded through a radical-polar crossover mechanism involving a key episulfonium ion intermediate. Subsequent electrochemical oxidation of fluorosulfides to fluorosulfoxides were readily achieved under a higher applied potential with the adventitious H2O in the reaction mixture.