Outline of CHN Elementary and CN Environmental Analysis

Wydrukowano z dostarczonych Wydawnictwu UŁ gotowych materiałówA review on the CHN analysis of organic compounds and the CN environmental analysis is described. The review contains outline of the evolutionary development of elementary analysis, since Gay-Lussac, Dumas and Liebig era until a present slate analysis, with computer controlled, fully automated analyzers. Physical principles of high temperature and low temperature combustions are discussed. Technical foundations on conjunctions of the high temperature combustion with chromatographic separations of the ultimate combustion products of organic samples, is delineated. Commercially available elemental analyzers are compared and their construction and operating principles are described. The basic methods of determination of environmental carbon and nitrogen are discussed. The representative analyzers for environmental carbon and nitrogen analysis are presented and their operating principles are described.Zadanie pt. Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki nr 885/P-DUN/2014 zostało dofinansowane ze środków MNiSW w ramach działalności upowszechniającej naukę

Analysis of Organophosphorus Compounds. 1. Application of Iodine-Azide Reaction for Detection of Thiophosphoorganic Compounds in Thin-Layer Chromatography

Wydrukowano z dostarczonych Wydawnictwu UŁ gotowych materiałówZadanie pt. Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki nr 885/P-DUN/2014 zostało dofinansowane ze środków MNiSW w ramach działalności upowszechniającej naukę

Aminophosphonic acids: phosphorus analogues of natural amino acids, part 1 : syntheses of alpha-aminophosphonic acids

This review presents a comprehensive account of methods which are commonly applied for the synthesis of alpha- aminophosphonic acids. In the following order, protocols based on the methodologies listed below are discussed: a) simultaneous formation of P-C-N systems; b) nucleophilic substitution with phosphoroorganic nucleophiles; c) additions of the P-H functions to multiple C-N bonds; d) alpha-amination of phosphonates and functionalized alkylphosphonates; e) modifications of the side chain of aminoalkylphosphonates; f) modifications of phosphorus functions and h) modifications of functions containing nitrogen

Reactivity of aminophosphonic acids: oxidative dephosphonylation of 1-aminoalkylphosphonic acids by aqueous halogens

The reactions of 1-aminoalkylphosphonic acids with bromine-water, chlorine-water and iodine-water were investigated. The formation of phosphoric(v) acid, as a result of a halogen-promoted cleavage of the C-alpha-P bond, accompanied by nitrogen release, was observed. The dephosphonylation of 1-aminoalkylphosphonic acids was found to occur quantitatively. In the reactions of 1-aminoalkylphosphonic acids with other halogen-water reagents investigated by P-31 NMR, scission of the C-alpha-P bond was also observed, the reaction rates being comparable for bromine and chlorine, but much slower for iodine

1-(Acylamino)alkylphosphonic Acids—Alkaline Deacylation

The alkaline deacylation of a representative series of 1-(acylamino)alkylphosphonic acids [(AC)-AAP: (AC) = Ac, TFA, Bz; AAP = GlyP, AlaP, ValP, PglP and PheP] in an aqueous solution of KOH (2M) was investigated. The results suggested a two-stage reaction mechanism with a quick interaction of the hydroxyl ion on the carbonyl function of the amide R-C(O)-N(H)- group in the first stage, which leads to instant formation of the intermediary acyl-hydroxyl adducts of R-C(O−)2-N(H)-, visible in the 31P NMR spectra. In the second stage, these intermediates decompose slowly by splitting of the RC(O−)2-N(H)- function with the subsequent formation of 1-aminoalkylphosphonate and carboxylate ions

1-(<i>N</i>-Acylamino)alkylphosphonic acids—Deacylation in aqueous solutions

<p></p> <p>The 1-(<i>N</i>-acylamino)alkylphosphonic acids (AC)-AA^P belong to the interesting and potentially of pharmacological importance group of 1-aminoalkylphosphonic acids derivatives. Since susceptibility of (AC)-AA^P on hydrolytic deacylation can form important factor influencing their biological activity, we have undertaken deacylation investigations of these compounds in aqueous media.</p> <p>In this article, we present our results on deacylation of various types of 1-(<i>N</i>-acylamino)alkylphosphonic acids (AC)-AA^P, including 1-(<i>N</i>-acetylamino)alkyl-phosphonic Ac-AA^P, 1-(<i>N</i>-chloroacetylamino)alkylphosphonic acids Mca-AA^P, 1-(<i>N</i>-trifluoroacetylamino)alkylphosphonic acids TFA-AA^P, and 1-(<i>N</i>-benzoylamino)-alkylphosphonic Bz-AA^P, derived from representative 1-aminoalkylphosphonic acids AA^P (Gly^P, Ala^P, Val^P, Pgl^P, and Phe^P) in neutral and 2 M HCl solutions.</p