N-based compounds

Many of the complexes which fall into this class are Pt(N N)-based compounds, where N N is a bidentate diimine ligand such as bipyridine or phenanthroline and derivatives thereof. As noted in Sect. 3, those where X = Cl are rarely significantly emissive, because the d-d state is either the lowest-energy excited state or is thermally accessible from a lower-lying CT or LC state [13]. 

Snarey M, N K Terrett, P Willett and D J Wilton 1997. Comparison of Algorithms for Dissimilaritj based Compound Selection. Journal of Molecular Graphics and Modelling 15 372-385. 

The first step is an example of 12-52 and intermediate N-halo amides (69) have been isolated. In the second step, 69 lose a proton to the base. Compound 69 are acidic because of the presence of two electron-withdrawing groups (acyl and halo) on the nitrogen. It is possible that the third step is actually two steps loss of bromide to... 

These calculations have been conducted on the basis of RHF optimized geometries, considering the 6-31G basis set for the n-alkane compounds (11), and the 6-31G basis set for the polyacene series (12). In both cases, the basis set contention has been checked by comparison with more thorough investigations on small compounds, such as ADC[3] calculations (11a) on n-butane based on the 6-31IG, 6-31G and 6-31G basis, or the MRSDCI ionization spectrum of ethylene as obtained by Murray and Davidson (33) using a 196-CGTO basis set. 

S. Bandyopadhyay, S.L. Agrawal, P. Sajith, N. Mandal, S. Dasgupta, R. Mukhopadhyay, A.S. Deuri, and S.C. Ameta, Research on the application of recycled waste RFL (Resorcinol-Formaldehyde-Latex) dip solid in Styrene Butadiene Rubber based compounds. Progress in Rubber, Plastics and Recycling Technology, 23(1), 21, 2007. 

The different classes of Ru-based catalysts, including crystalline Chevrel-phase chalcogenides, nanostructured Ru, and Ru-Se clusters, and also Ru-N chelate compounds (RuNj), have been reviewed recently by Lee and Popov [29] in terms of the activity and selectivity toward the four-electron oxygen reduction to water. The conclusion was drawn that selenium is a critical element controlling the catalytic properties of Ru clusters as it directly modifies the electronic structure of the catalytic reaction center and increases the resistance to electrochemical oxidation of interfacial Ru atoms in acidic environments. 

An attempt to estimate human daily impact of N nitroso compounds is shown in Table I. The apparent intake from food of preformed nitrosamines is comparatively low, at least in these surveys of a Western diet in England (3). The Intake directly to the respiratory tract from smoking could be somewhat larger. However, if the blood levels reported are confirmed as correct, then inputs of up to 700 meg per day of at least N nitrosodimethylamine (NDMA) may be calculated, based on pharmacokinetic considerations of data obtained in animals and extrapolated to man. It should be emphasized that no information is available at present on nitrosamide intake or in vivo formation, largely because of analytical limitations. 

The 2D model was built from a wide array of descriptors, including also E-state indices, by Simulations Plus [89], The model is based on the associative neural network ensembles [86, 87] constructed from n=9658 compounds selected from the BioByte StarList [10] of ion-corrected experimental logP values. The model produced MAE = 0.24, r = 0.96 (R. Fraczkiewicz, personal communication). 

Furthermore, a series of ternary compounds have been crystallized. Most work has been done on adducts with N bases. 

See Other PERCHLORATE SALTS OF NITROGENOUS BASES, N-O COMPOUNDS... 

See Phenylhydroxylaminium chloride See other N-O COMPOUNDS, ORGANIC BASES... 

See related N-S COMPOUNDS See other oxosalts of nitrogenous bases... 

Reaction of 2-oxo-4-thioxo-6-aminopyrimidine and the biselectrophile 218 under base catalysis formed either the pyrimido[l,6- ]pyrimidine 219 or the pyrido[2,3-<7]pyrimidine 220, depending on the X subsituent in 218. The N-bridgehead compound 219 formed if X = CONH2, CC Et, COPh, while 220 was obtained when X = CN, CSNH2 (Scheme 35) <2000HC0301>. 

The use of nitrogen fertilization results in higher content of N-containing compounds, including free amino acids, and also increases in terpene content in wood plants, whilst starch, total carbohydrates, phenylpropanoids and total carbon-based phytochemicals decreased (Koricheva et al., 1998). Higher levels of nitrogen favoured its uptake and increased the nitrate content of the crop, which is critical for salad vegetables and baby foods. 

The nature of the substituent directly attached to the N-atom influences the properties (basicity, reduction potential, etc.) of the C = N function more than the substituents at the carbon atom. For example, it was found that Ir-dipho-sphine catalysts that are very active for N-aryl imines are deactivated rapidly when applied for aliphatic imines [7], or that titanocene-based catalysts are active only for N-alkyl imines but not for N-aryl imines [8, 20, 21]. Oximes and other C = N-X compounds show even more pronounced differences in reactivity. 

N-Nitroso compounds have been found to exist as syn and anti rotamers [30, 31] due to restricted rotation of the N-N bond resulting from nitrogen lone-pair delocalization (Fig. 3.2). This delocalization causes the hydrogens at the a-carbons to become acidic as evident by their base-catalyzed reactions, such as exchange with deuterium... 

Data pertaining to affinity of organic N-bases towards nitrosonium cation are numerous 74-80), however, those for N-heteroaromatic compounds are limited 77-80). 

---