Heteroatom oxidations phosphorus

Since dioxiranes are electrophilic oxidants, heteroatom functionalities with lone pair electrons are among the most reactive substrates towards oxidation. Among such nucleophilic heteroatom-type substrates, those that contain a nitrogen, sulfur or phosphorus atom, or a C=X functionality (where X is N or S), have been most extensively employed, mainly in view of the usefulness of the resulting oxidation products. Some less studied heteroatoms include oxygen, selenium, halogen and the metal centers in organometallic compounds. These transformations are summarized in Scheme 10. We shall present the substrate classes separately, since the heteroatom oxidation is quite substrate-dependent. 

Reaction of tricoordinated phosphorus compounds with heteroatomic oxidizing agents... 

Oxidation of Phosphorus. In addition to the previously mentioned heteroatom oxidations, the oxidation of trialkyl phosphines to the corresponding trialkylphosphine oxides has been accomplished with nitric acid (eq 25). ... 

Phosphorus is the other heteroatom of major coupling importance to the organic chemist. Like 19F,31P has a spin of V2 and a 100 % natural abundance, so you know what to expect The actual size of the couplings observed with 31P can vary considerably, depending on the oxidation state of the 31P atom. You ll find some useful examples in Table 6.3. 

The reactivity of cyclic aminomethylphosphines is of special interest due to the presence of two or more heteroatoms capable of quartemization in a 1,3-position. Besides the ordinary oxidation of tricoordinated phosphorus, mutual transformations and rearrangements are typical. 

FAD dependent oxidation of nucleophilic nitrogen, sulfur and phosphorus heteroatoms, e.g. conversion of nicotine to nicotine l -iV-oxide, cimetidine to cimetidine S-oxide... 

The hydrolysis of VX and GB in hot sodium hydroxide solution and of mustard in hot water results in the formation of complex organic compounds. These molecules contain heteroatoms such as sulfur, chlorine, fluorine, and phosphorus, which, when oxidized, form acids. The excess sodium hydroxide present in the hydrolysate neutralizes these acids to form salts. For example, the following reactions are likely ... 

The products of hydrocarbon oxidation in SCWO are carbon dioxide and water. Heteroatoms are converted to inorganic compounds, usually acids, salts, or oxides in high oxidation states. Phosphorus is converted into phosphate, and sulphur to sulfate nitrogen-containing compounds are oxidized to nitrogen gas. Working at temperatures below 700 °C, no NOx is formed. 

Sections 10.5 through 10.8 envisage single or, more commonly, multiple replacements of the peptide bond functionality. In particular, substitutions characterized by single, double, or triple C—C bonds are covered in Section 10.5, while substitutions containing C/O, C/N, and C/N/O amide bond replacements are described in Sections 10.6,10.7, and 10.8, respectively. Sections 10.9 and 10.10 focus on the known types of sulfur- or phosphorus-based peptide bond replacements, 1,2 6 7 including different oxidation states of the heteroatoms. 

Anodic oxidation of organosilicon compounds bearing heteroatoms and its synthetic applications have been studied intensively. The oxidation potentials of organosilicon compounds bearing nitrogen, sulfur and phosphorus atoms at the a-, ji- and /-positions were shown in Table 512-21-23. it should be noted that the silyl group a to the heteroatom decreases appreciably the oxidation potential. 

The use of hypervalent iodine reagents for heteroatom-heteroatom bond forming reactions is well established in the context of classical oxidation chemistry [1-11]. For example, oxidations of anilines to azobenzenes, thiols to disulfides, and sulfides to sulfoxides with aryl-A3-iodanes were documented decades ago [1-5]. During the last ten years, particular attention has also been given to oxidative transformations of compounds derived from heavier elements, including the interception of reaction intermediates or initially formed products with external nucleophiles. A second important development is the utilization of sulfonyliminoiodanes, ArI = NS02R, for heteroatom-nitrogen bond formation, especially for imidations of sulfur, selenium, phosphorus and arsenic com-... 

FMOs, like CYP, are located in the endoplasmic reticulum and are involved in the oxidation of numerous organic xenobiotics containing nitrogen, sulfur, or phosphorus heteroatoms as well as some inorganic ions. 

Phosphacyclobutene P-oxides 64 are produced by the reaction of titanacyclobutenes with dichlorophenylphosphine <07CEJ4077>. The large instability of heterophosphete compounds 65, composed of a four-membered unsaturated ring with a pentavalent phosphorus atom and a heteroatom, has been identified and characterised by first-principle molecular orbital computations, at several levels of theory showing that strong electron-... 

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