Nitrogen, reactions with review

Acylation of l,3,4-thiadiazol-2-(3//)-ones is also possible although competitive reaction with the ring nitrogen atoms is often observed. This reaction has been reviewed in the Houben-Weyl Science of Synthesis <2004HOU(13)349>. 

Spencer and Brewer [144] have reviewed methods for the determination of nitrite in seawater. Workers at WRc, UK [ 145] have described an automated procedure for the determination of oxidised nitrogen and nitrite in estuarine waters. The procedure determines nitrite by reaction with N-1 naphthyl-ethylene diamine hydrochloride under acidic conditions to form an azo dye which is measured spectrophotometrically. The reliability and precision of the procedure were tested and found to be satisfactory for routine analyses, provided that standards are prepared using water of an appropriate salinity. Samples taken at the mouth of an estuary require standards prepared in synthetic seawater, while samples taken at the tidal limit of the estuary require standards prepared using deionised water. At sampling points between these two extremes there will be an error of up to 10% unless the salinity of the standards is adjusted accordingly. In a modification of the method, nitrate is reduced to nitrite in a micro cadmium/copper reduction column and total nitrite estimated. The nitrate content is then obtained by difference. 

Brief mentions of kinetics and mechanisms of reactions of nitrogen bases with a selection of palladium(II) complexes with ammine, amines, pyridine-2-carboxylate, pyridoxine, and related ligands are included in a review of analogous platinum(II) reactions (194). 

Although the generation of the corresponding a-nitrogen-substituted compound can be achieved in general in a highly enantioselective manner, a complication can result from the observation that the stereochemical outcome of the reaction with electrophiles (i.e. retention or inversion) depends on the nature of the electrophile and is not always uniform. The chemistry of lithiated carbamates has been reviewed in a comprehensive manner. ... 

Insertion of the Si=N bond into polar bonds is the most used reaction for the characterization of very reactive and transient silanimines. Especially, the reaction with alcohols is often the first reaction to be carried out with silicon-nitrogen multiple bond systems. Other reagents used for insertion reactions are amines, water and alkoxysilanes (equation 269)300,303,306,311,351-353. The insertion into E—X bonds (E = Si, Ge, Sn X = Cl, OR, NR2, N3) has been shown earlier in this review for the insertion into the Si—N bond of silyl azides310,351. A reaction reported is the insertion of 678 into the C—H... 

This review summarizes some earlier qualitative work as well as recent quantitative studies of redistribution equilibria and describes the principles underlying the mathematical treatment of such equilibria as well as the general implications of these equilibria with respect to general chemistry. In line with the general objective of the Advances in Organometallic Chemistry series, this article is limited to carbon-metal-bonded systems, metal hydrides, metal carbonyl compounds, metallocenes, and similar complexes. Excluded therefore are halogen-, sulfur-, nitrogen, and phosphorus-based systems.Various aspects of redistribution reactions were reviewed previously (42, 74, 87, 88,150,186, 285, 286, 288). 

The effect of substituents on benzenoid reactivity has been one of the most extensively investigated branches of chemistry. The scattered data on pyridine substitution are now assembled in a review by R. A. Abramovitch and J. G. Saha which is as valuable for showing what remains to be done as for what has been achieved. R. E. Lyle and P. S. Anderson survey reactions of nitrogen heterocycles with complex hydrides, and the heterocyclic chemistry of nitriles and nitrilium salts is covered by F. Johnson and R. Madronero. 

Flavor notes of products of amino compounds-sugars reaction were reviewed with emphasis on amino-ribose system. Meat-like flavor was imparted by browning reaction products of camosine-, citrul-line-, histidine-, glutamic-, 2-pyrrolidone-5-carboxylic-, methionine-, cysteine-, cysteic-, and taurine-ribose. Recent advancements in nitrogen-, oxygen- and sulfur hetercyclics and lipid browning were presented. 

Metal nitrene complexes were used in a number of C-H amination reactions (recent reviews [358, 359]). Copper ketiminate complexes react with azides to nitrene complexes, which were isolated [360]. (p-Ketiminate)copper(I) complex 262 (2.5 mol%) serves therefore as an efficient catalyst for the intermolecular C-H amination of alkylarenes, cycloalkanes, or benzaldehydes 260 using adamantyl azide 261 as the nitrogen source ig. 68) [361]. The corresponding adamantyl amines or amides 263 were isolated in 80-93% yield. Copper complex 262 forms initially a dinuclear bridged complex with 261. From this a copper nitrene complex is generated by elimination of nitrogen, which mediates the hydrogen abstraction from 260. 

The early syntheses of cyclic tin-nitrogen compounds were reviewed by Jones and Lappert in 1966 (108). The two most common preparative routes are transamination reactions (109) and reactions between R2SnCl2 and an alkali metal amide (110). Some examples are shown in Eqs. (24)-(26). Dilithio reagents analogous to 28 can react with other metal dihalides... 

Abstract Synthesis methods of various C- and /V-nitroderivativcs of five-membered azoles - pyrazoles, imidazoles, 1,2,3-triazoles, 1,2,4-triazoles, oxazoles, oxadiazoles, isoxazoles, thiazoles, thiadiazoles, isothiazoles, selenazoles and tetrazoles - are summarized and critically discussed. The special attention focuses on the nitration reaction of azoles with nitric acid or sulfuric-nitric acid mixture, one of the main synthetic routes to nitroazoles. The nitration reactions with such nitrating agents as acetylnitrate, nitric acid/trifluoroacetic anhydride, nitrogen dioxide, nitrogen tetrox-ide, nitronium tetrafluoroborate, V-nitropicolinium tetrafluoroborate are reported. General information on the theory of electrophilic nitration of aromatic compounds is included in the chapter covering synthetic methods. The kinetics and mechanisms of nitration of five-membered azoles are considered. The nitroazole preparation from different cyclic systems or from aminoazoles or based on heterocyclization is the subject of wide speculation. The particular section is devoted to the chemistry of extraordinary class of nitroazoles - polynitroazoles. Vicarious nucleophilic substitution (VNS) reaction in nitroazoles is reviewed in detail. 

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