Chemistry of α-Nitrohetero-organic Compounds

Abstract

We study the level spacing distribution p(s) in the spectrum of random networks. According to our numerical results, the shape of p(s) in the Erdős-Rényi (E-R) random graph is determined by the average degree k and p(s) undergoes a dramatic change when k is varied around the critical point of the percolation transition, k = 1. When k 1, the p(s) is described by the statistics of the Gaussian orthogonal ensemble (GOE), one of the major statistical ensembles in Random Matrix Theory, whereas at k = 1 it follows the Poisson level spacing distribution. Closely above the critical point, p(s) can be described in terms of an intermediate distribution between Poisson and the GOE, the Brodydistribution. Furthermore, below the critical point p(s) can be given with the help of the regularized Gamma-function. Motivated by these results, we analyse the behaviour of p(s) in real networks such as the internet, a word association network and a protein-protein interaction network as well. When the giant component of these networks is destroyed in a node deletion process simulating the networks subjected to intentional attack, their level spacing distribution undergoes a similar transition to that of the E-R graph.

A DFT Study on the Mechanism of the Annulation Reaction of Trichloronitroethylene with Aniline in the Synthesis of Quinoxalinone-N-oxides

“…These processes may be used to readily assemble molecules with extended carbon frameworks . Heteroatom-substituted nitroalkenes are particularly useful compounds for the controlled synthesis of heterocyclic or related molecules. − Halogenated nitroalkenes as reactive electrophiles undergo Michael addition reactions with nucleophiles. In these reactions, the halogen substituent is usually displaced after the Michael addition.…”

Synthesis, reactions, and properties of oxygen-nitrogen-oxygen systems

“…This reaction has been studied in detail and widely applied in organic synthesis due to the easy transformation of its products, 2-alkoxy-or 2-(silyloxy)isoxazolidines into compounds of various types. [15][16][17][18][19][20][21][22][23] Some other trends in this field were successfully developed along with the above mentioned, and at the present time almost all possible types of acyclic and cyclic compounds of general formula XN(OR)j, where X = alkyl, RO, H, Hal, (RO)2N, RCO or unpaired electron have been synthesized. They are of special interest mainly due to the fact that, for example, the first two in this series represent the nitrogen analogues of such well-studied compounds as acetals, orthoesters of carboxylic acids or phosphonous diesters and trialkyl phosphites, respectively.…”