Propylene oxide deuterated

The propylene oxide complex not only dissociated into its components but also transformed to either an oligomer or a polymer of propylene oxide when it was allowed to stand in solution. This transformation could be followed by H-NMR techniques with the use of a-deuterated propylene oxide instead of the non-deuterated one. Its rate depended on the nature of solvent and on the temperature. This experimental result implies that the monomer liberated by dessociation of the complex is polymerized by the catalyst, that only a minute fraction of the organozinc component of the complex actually acts as a catalyst for polymerization, and that the rate of propagation is far faster than that of initiation. These implications together with the evidence that coordination of the monomer to the catalyst is a prerequisite for the stereospecific polymerization led us to the detailed studies of the bulk polymerization, that is, the polymerization of propylene oxide in propylene oxide solution. 

Oguni,N., Fujita,T., Tani.H. Stereospecific polymerization of propylene oxide and its a-deuterated derivative by bis(ethylzinc) t-butylamine in the presence of water as a catalyst (in preparation). 

The use of isotopic tracers has demonstrated that the selective oxidation of propylene proceeds via the formation of a symmetrical allyl species. Probably the most convincing evidence is presented by the isotopic tracer studies utilizing, 4C-labeled propylene and deuterated propylene. Adams and Jennings 14, 15) studied the oxidation of propylene at 450°C over bismuth molybdate and cuprous oxide catalysts. The reactant propylene was labeled with deuterium in various positions. They analyzed their results in terms of a kinetic isotope effect, which is defined by the probability of a deuterium atom being abstracted relative to that of a hydrogen atom. Letting z = kD/kH represent this relative discrimination probability, the reaction paths shown in Fig. 1 were found to be applicable to the oxidation of 1—C3He—3d and 1—QH —1 d. 

Oxidation of Deuterated Propylene over Bismuth Molybdates" ... 

Studies using a deuterated version of 9 revealed that the non-coordinating l-methoxypropan-2-olate groups initiated the polymerization by attack on the propylene oxide monomer, whereas the coordinated l-methoxypropan-2-olate groups provided the chiral structure, which remained unchanged during the polymerization. When these... 

To test this hypothesis, propylene was oxidized on a deuterated catalyst surface. The ir-allyl route would yield acrolein containing no deuter-... 

The reaction of propylene on ZrC>2 exhibits the same characteristics as on other oxides. Propane-d2, for example, is selectively formed in the deuteration process, with no hydrogen exchange in propylene215. New features appear, however, when zirconia is dispersed on other oxides (alumina, silica, titania)215,216. A considerable rate increase is observed and exchange in propylene proceeds simultaneously with addition via the associative mechanism through the common intermediate n-propyl and s-propyl species. 

The simplest alkene of this subgroup is propylene. Its first vacuum UV photochemistry study was published in 1965 (33) and was followed by several others (34-36). For example, at 147.0 nm, many products were identified. From partially deuterated material, as well as from the effect of added nitric oxide, the molecular formation of hydrogen and methane was observed as well as those of hydrogen... 

PDMS polydimethylsiloxane, PE polyethylene, PVP polyfiV-vinylpyrrolidone), PEP polyfethyl-ene propylene), dPEP deuterated polyfethylene propylene), PLA polyfc.L-lactide), PEO poly (ethylene oxide)... 

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