Metal deuterium oxide

When we allowed pentafluorophenyl-lithium to decompose in ether in the presence of an excess of N, ZV-dimethy laniline we obtained the compounds (92) 70, X = F), (94), the latter as the major compound, and a product which was shown to be (97). That this latter compound did not arise by metallation of 2V,lV-dimethylaniline followed by addition to tetrafluorobenzyne was shown by quenching the reaction mixture with deuterium oxide. No deuterium incorporation was detected. The compound (97) provides a rare example of a product derived by a Stevens rearrangement in which aryl migration has occurred b>. 

See Pentafluorophenyllithium Deuterium oxide See Diprotium monoxide See other non-metal oxides... 

Various organolithium intermediates may be posmlated for the synthesis of functionalized indoles and other heterocyclic compounds, from substituted Af-allylanilines (331a-c) or the cychc analog 332, on treatment with f-BuLi. For example, in equation 81 intermediate 333, derived from 331a, was quenched with deuterium oxide. Participation of benzyne metallated intermediates, such as 334, derived from 332, is surmised in equation 82 and other processes. The products of equations 81 and 82 can be characterized by H and NMR spectra . 

A mechanism which is consistent with the various experimental results for olefin formation involves the initial abstraction of the hydrazone proton (103 - 106)82 In this case, however, expulsion of the tosylate anion is associated with the abstraction of a second hydrogen from C-16 instead of hydride attack on the C=N bond (compare 97 - 98 and 106 - 107). Expulsion of nitrogen from the resulting intermediate (107) yields an anion (108) which is most probably stabilized in the form of a metal complex and can be readily decomposed by water to give an olefin (109). This implies that 17-d1-androst-16-ene (104) can be prepared by using deuterium oxide as the sole deuterated reagent.82... 

The metal-containing hydrogenases also catalyze hydrogen isotope exchange [44], for example, between H2 gas and deuterium oxide, yielding varying proportions of isotopically labeled hydrogen gas ... 

When deuterium oxide is used as D source, the reaction temperature should be considered. When water in a closed pot is heated beyond the boiling point, it becomes subcritical and, eventually, supercritical [12]. Water under these conditions should also have potential in organic reactions [13, 14]. The same should happen with deuterium oxide. The value of p K%v for subcritical water should be noted. It has the low value of ca. 11 under typical hydrothermal conditions (250°C/4—5 MPa). This means that hydrothermal deuterium oxide ionizes to a greater extent than under ambient conditions (1000 times more) and several acid-catalyzed reactions can actually be performed conveniently under supercritical or subcritical conditions without adding any acid. It is also interesting to perform transition metal-catalyzed reactions under hydrothermal conditions. Under these conditions, one should consider the redox equilibrium shown in Scheme 4 [15]. 

For each of the alkali metals used the e.s.r. spectrum at 77°K consisted of a single narrow line (Fig. 12a, b). The relevant features of the e.s.r. spectra are summarized in Table 4. The absence of any effect of the cation on the line width or p-factors shows conclusively that the electron has been transferred completely from the alkali metal atom and is therefore not held in an expanded orbital around the cation, as suggested by Jortner and Sharf (1962). The difference in line width between the spectra in D2O (3-2 G) and in water (9-2 G) suggests that there is a hyperline interaction between the electron and the protons in water. This was shown conclusively by the observation of seven equally spaced hyperfine lines when a deposit prepared from water was warmed carefully (Fig. 12c), whereas no hyperfine structure was observed from a sample containing deuterium oxide. The hyperfine structure shows that the electron interacts primarily with six protons and that it is not delocalized over a large number of water molecules but is located in a well-defined trap surrounded by these protons. 

When copper or iron strips were placed in water after long exposure to benzyl bromide vapors, they showed much greater dissolution than unexposed strips (Table IV) (97). Replacement of water by deuterium oxide as the reaction medium yielded CHjD as the primary gaseous products (97). While this would arise from the hydrolysis of a metal-methyl bond ... 

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