Nitrogen sulfide, selenide

Nitrogen and sodium do not react at any temperature under ordinary circumstances, but are reported to form the nitride or azide under the influence of an electric discharge (14,35). Sodium siHcide, NaSi, has been synthesized from the elements (36,37). When heated together, sodium and phosphoms form sodium phosphide, but in the presence of air with ignition sodium phosphate is formed. Sulfur, selenium, and tellurium form the sulfide, selenide, and teUuride, respectively. In vapor phase, sodium forms haHdes with all halogens (14). At room temperature, chlorine and bromine react rapidly with thin films of sodium (38), whereas fluorine and sodium ignite. Molten sodium ignites in chlorine and bums to sodium chloride (see Sodium COMPOUNDS, SODIUM HALIDES). 

The organic substrates in Chart 8 can be divided into two main categories in which (i) the oxidation of olefins, sulfides, and selenides involves oxygen atom transfer to yield epoxides, sulfoxides, and selenoxides, respectively, whereas (ii) the oxidation of hydroquinones and quinone dioximes formally involves loss of two electrons and two protons to yield quinones and dinitrosobenzenes, respectively. In order to provide a unifying mechanistic theme for the seemingly disparate transformations in Chart 8, we note that nitrogen dioxide exists in equilibrium with its dimeric forms, namely, the predominant N—N bonded dimer 02N—N02 and the minor N—O bonded isomer ONO—N02 (equation 88). 

Oxidation-sensitive functionalities other than alcohols are remarkably resistant to the action of the TFAA-mediated Moffatt oxidation. Functional groups resistant to this oxidation include p-methoxybenzyl ethers133 and esters,143 sulfides,143a 144 thioacetals,145 nitrogen heterocycles146 and most peculiarly even selenides,147 and p-hydroquinones.148... 

Two kinds of donors can be considered (1) a-donors that possess nonbonding electrons, such as various nitrogen bases (e.g. amines, pyridines, and nitriles), oxygen bases (e.g. alcohols, ethers, and carbonyl compounds), and organic sulfides and selenides, forming a-a complexes (2) tt-donors in which the donor function is performed by bonding n-orbitals such as in aromatic compounds (e.g. benzene and polycyclic aromatics), forming a-n complexes. 

Solubilities given for those gases which react with water, namely ozone, nitrogen oxides, chlorine and its oxides, carbon dioxide, hydrogen sulfide, hydrogen selenide and sulfur dioxide, are recorded as bulk solubilities i.e., all chemical species of the gas and its reaction products with water are included. 

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