Trans— nitrate

M.I. Fauth H. Stalcup, AnalChem 30,1670— 72(1958) Be CA 53, 2929(1959) [Evaluation of six methods for detn of nitrogen in NGu. (Nitro N methods tested are modified nitrometer — greatest precision of the six acetate-buffered titanous chloride transnitration with sulfuric acid and Bowman-Scott). Total N methods are modified Kjeldahl and micro-Dumas — better of these two. The titanous chloride and trans-nitration methods are satisfactory]... 

Both isomers hydrolyze in water to the corresponding aquo complexes. The rate of hydrolysis may be decreased by keeping the solutions at 0°. The cis isomer exhibits a broad absorption band in the visible region of the spectrum at 540 mu, while the trans form absorbs at 640 m/. The cis isomer has a solubility of 2.6 X 10 mol/1. in water at 0°, while the trans nitrate dissolves to the extent of 7.7 X 10 mol/1. Evaporation of the aqueous solutions with concentrated hydrobromic acid converts the complexes into the corresponding dibromo compounds. 

ClHgNjOgPt, Platinum(II), diamineaqua-chloro-, trans-, nitrate, 22 125 CIIrOPCi7H22, Iridium(I), carbonylchlorobis-(dimethylphenylphosphine)-, trans-, 21 97... 

Another, lengthier, method Involving trans-nitration of salicylic acid by the NGu is described in Ref 4. It may not retain otherwise gpod accuracy on very finely divided NGu. 

PtClH N304, Platinum(Il), dianunineaqua-chlmo-, trans-, nitrate, 22 125 PtClo3i S2N4C4, Platinate, tetracyano-, cesium chloride (1 2 0.30), 21 142 PtClo.3oN4Rb]C4 3H2O, Platinate, tetracyano-, rubidium chloride (1 2 0.30), trihydiate, 21 145... 

Cupric nitrate (3H2O) [10031-43-3 (3H2O) 3251-23-8 (anhydr)] M 241.6, m 114 , b 170 (dec), d 2.0. Crystd from weak aqueous HNO3 (0.5mL/g) by cooling from room temperature. The anhydrous salt can be prepared by dissolving copper metal in a 1 1 mixture of liquid NO2 and ethyl acetate and purified by sublimation [Evans et al. J Chem Soc, Faraday Trans 1 75 1023 1979], The hexahydrate dehydr to trihydrate at 26°, and the anhydrous salt sublimes between 150 and 225°, but melts at 255-256° and is deliquescent. 

Lead nitrate [10099-74-8] M 331.2, m 470°. Ppted twice from hot (60°) cone aqueous soln by adding HNO3. The ppte was sucked dry in a sintered-glass funnel, then transferred to a crystallising dish which was covered by a clock glass and left in an electric oven at 110° for several hours [Beck, Singh and Wynne-Jones Trans Faraday Soc 55 331 1959], After 2 recrystns of ACS grade no metals above 0.001 ppm were detected. 

Another way of replacing chloride trans to phosphine involves using silver salts reaction with AgPF6 and AgN03 introduces, respectively, a water molecule (XII) and a nitrate group (IX), which may in turn be replaced by a range of Lewis bases, giving (VIII), (X) and (XXV). 

Another example of reactivity difference lies in the reaction with silver nitrate. Solutions of the c/s-isomer react with silver nitrate in a few hours at room temperature while the trans-isomer needs refluxing for many hours to remove all the chloride [71, 72, 74], A quantitative method for measuring concentrations of each isomer in mixtures involves reaction... 

Trans-l and ds-3-bromoflavanone Ih were synthesized by the use of the v procedure of Bognar et al. (ref. 9). Cyclohexyl amine and N,N-dimethylformamide (DMF) was purified by distillation, potassium nitrate (Reanal) was used as received. 

Detection of an Intermediate. In many cases, an intermediate cannot be isolated but can be detected by IR, NMR, or other spectra. The detection by Raman spectra of NOj was regarded as strong evidence that this is an intermediate in the nitration of benzene (see 11-2). Free radical and triplet intermediates can often be detected by ESR and by CIDNP (see Chapter 5). Free radicals [as well as radical ions and EDA complexes] can also be detected by a method that does not rely on spectra. In this method, a doublebond compound is added to the reaction mixture, and its fate traced. One possible result is cis-trans conversion. For example, cis-stilbene is isomerized to the trans isomer in the presence of RS- radicals, by this mechanism ... 

S. Santi, A. de Marco, G. Locci, S. Cesco, R. Pinton, and Z. Varanini. Possible involvement of root plasma membrane H -ATPa.se isoforms in the induction of nitrate tran.sport. Proc. 6th hit. Symp. Genetics and Molecular Biology of Plant Nutrition. Elsinore, Denmark, 1998, Mbl. 

Figure 3 Gradient separation of anions using suppressed conductivity detection. Column 0.4 x 15 cm AS5A, 5 p latex-coated resin (Dionex). Eluent 750 pM NaOH, 0-5 min., then to 85 mM NaOH in 30 min. Flow 1 ml/min. 1 fluoride, 2 a-hydrox-ybutyrate, 3 acetate, 4 glycolate, 5 butyrate, 6 gluconate, 7 a-hydroxyvalerate, 8 formate, 9 valerate, 10 pyruvate, 11 monochloroacetate, 12 bromate, 13 chloride, 14 galacturonate, 15 nitrite, 16 glucuronate, 17 dichloroacetate, 18 trifluoroacetate, 19 phosphite, 20 selenite, 21 bromide, 22 nitrate, 23 sulfate, 24 oxalate, 25 selenate, 26 a-ketoglutarate, 27 fumarate, 28 phthalate, 29 oxalacetate, 30 phosphate, 31 arsenate, 32 chromate, 33 citrate, 34 isocitrate, 35 ds-aconitate, 36 trans-aconitate. (Reproduced with permission of Elsevier Science from Rocklin, R. D., Pohl, C. A., and Schibler, J. A., /. Chromatogr., 411, 107, 1987.)...

Figure 4 The variation of the zeta potential of vitreous silica as a function of pH in potassium nitrate solutions. (Based on Wiese, G. K., James, R. O., and Healy, T. W., Trans. Farad. Soc., 52, 1298, 1971.)...

Satsuma, A., Enjoji, T., Shimizu, K.I. et al. (1998) Reactivity of surface nitrate species in the selective reduction of NO with propene over Na-H-mordenite as investigated by dynamic FTIR spectroscopy,./. Chem. Soc., Faraday Trans., 94, 301. 

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