88563-82-0Relevant academic research and scientific papers
In Situ Generated Gold Nanoparticles on Active Carbon as Reusable Highly Efficient Catalysts for a Csp3 ?Csp3 Stille Coupling
Holz, Julia,Pfeffer, Camilla,Zuo, Hualiang,Beierlein, Dennis,Richter, Gunther,Klemm, Elias,Peters, René
supporting information, p. 10330 - 10334 (2019/06/27)
Gold nanoparticle catalysts are important in many industrial production processes. Nevertheless, for traditional Csp2-Csp2 cross-coupling reactions they have been rarely used and Pd catalysts usually give a superior performance. Herein we report that in situ formed gold metal nanoparticles are highly active catalysts for the cross coupling of allylstannanes and activated alkylbromides to form Csp3-Csp3 bonds. Turnover numbers up to 29 000 could be achieved in the presence of active carbon as solid support, which allowed for convenient catalyst recovery and reuse. The present study is a rare case where a gold metal catalyst is superior to Pd catalysts in a cross-coupling reaction of an organic halide and an organometallic reagent.
PYRIDINONE DICARBOXAMIDE FOR USE AS BROMODOMAIN INHIBITORS
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Page/Page column 71, (2017/03/21)
The present invention relates to compounds of formula (I) and salts thereof, pharmaceutical compositions containing such compounds and to their use in therapy.
MODULATORS OF METHYL MODIFYING ENZYMES, COMPOSITIONS AND USES THEREOF
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Paragraph 00340, (2013/08/28)
Agents for modulating methyl modifying enzymes, compositions and uses thereof are provided herein.
The ion-pair mechanism and bimolecular displacement at saturated carbon. VI. Razemization and radio-bromide exchange for substituted 1-phenylbromoethanes; solvent effects
Stein, Allan R.
, p. 363 - 371 (2007/10/02)
Racemization and radio-bromide exchange kinetics for 1-phenylbromoethanes in acetonitrile and in nitromethane using tetrabutylammonium bromide are reported.The results, together with those previously reported for acetone solutions, provide direct empirical support for the ion-pair mechanism for nucleophilic substitution at saturated carbon.Changing the substituents on the phenyl from the 4-nitro through to the 3,4-dimethyl substrate and the solvent from acetone to the more polar acetonitrile and nitromethane shifts the transition state for bromide substitution from an early to a late stage of the equilibria series substrate intimate ion pair various solvated ion pairs free or dissociated ions.For all the substrates in acetone and, for the species giving the less stable carbocations, in acetonitrile and nitromethane, both racemizations and exchanges are bimolecular.In the latter solvents, the substrates giving the more stable carbocations show mixed kinetics.
Studies in Nucleophilic Substitutions: Part I - Reactions between Phenylmethylcarbinols and Hydrobromic Acid and Structure-Reactivity Analysis
Ramakrishnan, S.,Venkatasubramanian, N.
, p. 60 - 62 (2007/10/02)
The kinetics of the reactions of phenylmethylcarbinol (PMC) and substituted PMCs with hydrobromic acid have been studied in 100percent acetic acid.The reaction rate follows total second order, first order each in and .The effect of substituents in the phenyl ring on the rate of substitution has been studied.The analysis of the rate data in terms of the Hammett equation gives a concave-down type of curve, though the Exner plot is linear.A stepwise mechanism involving the equilibrium formation of the conjugate acid of the alcohol followed by an attack by Br(-) accounts for the observed structure-reactivity pattern.
Process for the preparation of substituted vinylbenzyl chloride
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, (2008/06/13)
An improved continous single step vapor phase process for the preparation of substituted vinylbenzyl chloride from substituted ethyltoluene is disclosed. In this process a substituted ethyltoluene is reacted with a halogen gas in the vapor phase, at elevated temperatures via a continuous feed process. Furthermore, this process achieves halogenation followed by dehydrohalogenation in a single pass through the reactor. There is also obtained a very high total selectivity to vinylbenzyl chloride and its precursors via this continuous process.
