Deuterium hydrogenation with

On to another nuclear interaction. LeCs take a nucleus of deuterium (hydrogen with a neutron) and a nucleus of tritium (hydrogen with two neutrons) and slam... 

Researchers have been interested in heavy hydrogen since the early 1900s when Harold Urey, a chemistry professoratColum-bia University, developed a method of distilling liquid hydrogen to make deuterium—hydrogen with a neutron connected to the proton—an achievement for which he won the 1934 Nobel Prize in chemistry. 

Xi M and Bent B E 1993 Reaction of deuterium atoms with cyclohexane on Cu(111)—hydrogen abstraction reactions by Eley-Rideal mechanisms J. Phys. Chem. 97 4167... 

The earliest attempts to prepare deuterated steroids were carried out by exchange reactions of aliphatic hydrogens with deuterium in the presence of a surface catalyst. Cholesterol, for example, has been treated with platinum in a mixture of deuterium oxide and acetic acid-OD, and was found to yield... 

The rate of hydrogen (or deuterium) uptake with homogeneous catalysts is usually faster in benzene-alcohol (methanol or ethanol) solvent systems or in acetone than in tetrahydrofuran or in benzene alone. Whereas... 

The interaction of hydrogen (deuterium) molecules with a transition metal surface c an be conveniently described in terms of a Lennard--Jones potential energy diagram (Pig. 1). It cxxislsts of a shallcw molecular precursor well followed by a deep atomic chemisorption potential. Depending on their relative depths and positions the wells m or may not be separated by an activation energy barrier E as schematically Indicated by the dotted cur e in Fig. 1. 

Neither tritium or deuterium gas, with zero dipole moments, can be expected to interact positively with microwave radiation. Their low solubilities are seen as a further disadvantage. Our thoughts therefore turned towards an alternative procedure, of using solid tritium donors and the one that has found most favor with us is formate, usually as the potassium, sodium or ammonium salt. Catalytic hydrogen transfer of this kind is remarkably efficient as the results for a-methylcinnamic acid show [50]. The thermal reaction, when performed at a temperature of 50 °C, takes over 2 h to come to equilibrium whereas the microwave-enhanced reaction is complete within 5 min. A further advantage is that more sterically hindered al-kenes such as a-phenylcinnamic acid which are reduced with extreme difficulty when using H2 gas and Wilkinson s catalyst are easily reduced under microwave-enhanced conditions. 

A mixture of exo- and endo-isomers of 5-methylbicylo[2.2.1]hept-2-ene is hydrogenated with the aid of five equivalents of triethylsilane and 13.1 equivalents of trifluoroacetic acid to produce a 45% yield of < <7o-2-methylbicylo[2.2.1] heptane (Eq. 71). The same product is formed in 37% yield after only five minutes. The remainder of the reaction products is a mixture of three isomeric secondary exo-methylbicylo[2.2.1]heptyl trifluoroacetates that remains inert to the reaction conditions. Use of triethylsilane-l-d gives the endo-2-methylbicylo-[2.2.1]heptane product with an exo-deuterium at the tertiary carbon position shared with the methyl group. This result reflects the nature of the internal carbocation rearrangements that precede capture by the silane.230... 

Fig. 6. Raman spectra of localized vibrations due to nB and 10B in Si before (control) and after passivation by hydrogen or deuterium. [ Reprinted with permission from The Materials Research Society, Stutzmann, M. and Herrero, C.P. (1988). Defects in Electronic Materials, MRS Proceedings 104 (eds. M. Stavola, S.J. Pearson and G. Davies), p. 271. Also from Stutzmann and Herrero, 1988. And with permission from The American Physical Society, Herrero, C.P. and Stutzmann, M. (1988). Phys. Rev. B 38, 12668.]...

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