29559-55-5Relevant academic research and scientific papers
Steric effect of the dithiolato linker on the reduction mechanism of [Fe2(CO)6{μ-(XCH2)2CRR′}] hydrogenase models (X = S, Se)
Trautwein, Ralf,Almazahreh, Laith R.,G?rls, Helmar,Weigand, Wolfgang
supporting information, p. 18780 - 18794 (2015/11/11)
Studying the redox features of the [FeFe]-hydrogenase models is essential for understanding the function of the H cluster. The reduction of the [FeFe]-hydrogenase models of the type [Fe2(CO)6{μ-(XCH2)2E}] (X = S, Se) is described to occur either via sequential transfer of two electrons at and for the first and the second reduction steps, respectively, where, or via transfer of two electrons at the same applied potential due to potential inversion of the two reduction steps, i.e. Typically, the phenomenon of potential inversion is observed when a structural change intervenes in the cathodic process stabilizing the reduced species. In this report, we investigate the mechanism of the cathodic process of series of models [Fe2(CO)6{μ-(XCH2)2E}] (X = S or Se and E = CH2, CHMe or CMe2) applying cyclic voltammetry. The studies herein show the remarkable influence of the steric bulk of E toward the cathodic process, such that only complexes with E = CMe2 are reduced with inverted potentials due to occurrence of an ECE mechanism (E = electrochemical process, C = chemical process) of reduction. Moreover, we describe the catalytic behaviour of these models toward reduction of protons using acetic acid, AcOH, as a proton source.
Method for Chlorinating Alcohols
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Page/Page column 5, (2008/12/07)
A process for preparing organic chlorides in which the chlorine atom is bonded to a CH2 group by reacting the corresponding alcohols with thionyl chloride in the presence of a triaylphosphine oxide at a temperature of from 20 to 200° C. and a pressure of from 0.01 to 10 MPa abs, which comprises using the triarylphosphine oxide in a molar ratio to the amount of OH groups to be chlorinated of from 0.0001 to 0.5.
Viscosity-dependent cage reactions. Multiple substitutions in radical-chain chlorinations
Tanner, Dennis D.,Oumar-Mahamat,Meintzer, Christian P.,Tsai, Eve C.,Lu, Thanh T.,Yang, Dilun
, p. 5397 - 5402 (2007/10/02)
The mechanism by which the free-radical chlorination of alkanes produces polychlorides has been explained by the assumption that the geminate chlorine atom-chloroalkane pair react in their solvent cage at rates competitive with their diffusion from, and rotation in, the cage in which they are born. The major piece of evidence supporting this mechanism is that as the concentration of alkane is increased, polyhalogenation decreases. As the hydrocarbon that makes up the "cage walls" becomes more concentrated, the surrounding hydrocarbon scavenges the caged chlorine atoms before they react with their geminate chloroalkane. In the inert solvents in which these reactions take place, CCl4 or various Freons, the viscosity of the solvent is decreased with increasing concentration of hydrocarbon, and the diffusion rates are therefore increased. The diffusion dependence (i.e., viscosity) of the amount of polychlorination is an important component of the observed concentration dependence. The influence of the changing viscosity upon the production of polychlorination becomes more important as the hydrocarbon (neopentane, 2,3-dimethylbutane, or cyclohexane) makin up the cage walls becomes less reactive. The viscosity dependence of cage rotation was observed in solvents of high viscosity for the least reactive hydrocarbon, neopentane.
