4-Nitro-o-phenylenediamine

Shimoishi [ 555 ] determined selenium by gas chromatography with electron capture detection. To 50-100 ml seawater was added 5 ml concentrated hydrochloric acid and 2 ml 4-nitro-o-phenylenediamine (1%) and, after 2 hours, the product formed was extracted into 1 ml of toluene. The extract was washed with 2 ml of 7.5 M hydrochloric acid, then a sample (5 pi) was injected into a glass gas-liquid chromatography column (lm x 4 mm) packed with 15% of SE-30 on Chromosorb W (60-80 mesh) and operated at 200 °C with nitrogen (53 ml/min) as carrier gas. There is no interference from other substances present in seawater. The detection limit is 5 ng/1 with 200 ml samples, and the precision at a Se level of 0.025 pg/1 is 6%. 

Selenium Selenium complexed with 4-nitro-o-phenylenediamine, extracted into toluene Gas chromatography — [555]... 

One millilitre of sediment solution was allowed to stand with O.lmT of the 1% 4-nitro-o-phenylenediamine hydrochloride solution in a 10 mL glass vial for 2h. One millilitre of toluene was added. The vial was capped and shaken vigorously for 2min. One microlitre of the toluene layer was injected into the gas chromatograph. 

Selenium forms a volatile derivative, piazselenol, which can be subjected to GC analysis (Scheme 5.39). Young and Christian [612] treated selenium with 2,3-diaminonaph-thalene at pH 2.0 and extracted the resulting piazselenol into -hexane. With the use of an ECD, down to 5 10-I° g of selenium could be detected. The procedure, applied to the analysis of selenium in human blood, urine and river water, led to results equivalent to those obtained by neutron activation analysis. Similarly, Nakashima and Toei [613] performed the reaction of selenium (as selenious acid) with 4-chloro-o-phenylenediamine at pH 1 and extracted the derivative into toluene. They reported a detection limit of 0.04 jug. Shimoishi [614] analysed the content of selenium in metallic tellurium by this method. The sample was dissolved in aqua regia, followed by reaction with 4-nitro-o-phenylenediamine and extraction into toluene. Down to 10 ng of selenium could be determined using only a few milligrams of sample. Common ions did not interfere even when present in a large excess. Selenium in marine water was determined after the same derivatization step [615],... 

In this method, samples are spiked with a known amount of an enriched isotope of selenium ( Se in this case) and wet digested to destroy the organic matter and render all of the selenium into the oxidation state. Next, the selenium is reacted with 4-nitro-o-phenylenediamine (NPD) to form the nitropiazselenol (Se-NPD) which is extracted into chloroform. Aliquots of the extract are then introduced into the mass spectrometer (MS) via a gas chromatograph (GC) and individual ions measured to determine isotope ratios of the various selenium isotopes. From the observed isotope ratios and the known amount of Se spike added, the amounts of enriched tracer (e.g.,... 

The Element.—Analytical methods for the determination of trace quantities of selenium in two very different materials have been described. The first275 employs the use of flameless atomic absorption spectrophotometry for the direct determination of selenium (and Pb, Bi, Se, Te, and Tl) at p.p.m. levels in high-temperature alloys. The second method276 is able to determine the selenium content of plant material at levels as low as 0.005 fxg g The method involves the reaction of SeIV with 4-nitro-o-phenylenediamine to form 5-nitropiaselenol, which may be detected by means of a gas chromatograph. 

Reaction of o-phenylenediamine and n-butyl glyoxylate gives quinoxalin-2-one in excellent yield with 4-nitro-o-phenylenediamine (5) a mixture of 6- and 7-nitro-quinoxalin-2-ones, (6) and (7), is obtained.9... 

Complexes of selenium with xanthate [17], 4-nitro-o-phenylenediamine (toluene) [18], and DDTC [19,20] have also been used in extractive separation of Se from many elements. 

Aggarwal SK, Kinter M, Herold DA. 1992. Determination of selenium in urine by isotope dilution gas chromatography-mass spectrometry using 4-nitro-o-phenylenediamine, 3,5-dibromo-o-phenylenediamine, and 4-trifluoromethyl-o-phenylenediamine as derivatizing reagents. Anal Biochem 202(2) 367-374. 

Quinoxaline-2,3-diones are conveniently prepared by boiling a mixture of the o-phenylenediamine with oxalic acid dihydrate in 4 M hydrochloric acid. Alternatively a mixture of the diamine is refluxed with excess diethyl oxalate under an air condenser so that the ethyl alcohol formed by intermolecular condensation is allowed to escape (Scheme 19). 6-Nitroquinoxaline-2,3-dione has been prepared by fusion of 4-nitro-o-phenylenediamine with oxalic acid at 160° in this preparation diethyl... 

In 1993, Kashman et al. reported the synthesis of 7-phenylascididemin (356) (Scheme 41) (160), which was obtained during their synthetic studies toward the total synthesis of eilatin (413) (160). A double Skraup reaction between 4-nitro-o-phenylenediamine (353) and two moles of 3 -chloropro-piophenone (354) gave the diphenylphenanthroline 355, which, upon heating in dodecane under N2 in the presence of (EtO)3P, unexpectedly yielded... 

Hazardous Decomp. Prods. Heated to decomp., emits toxic vapors of NOx Uses Colorant in hair dyes intermediate for prep, of oxidation color systems Trade Name Synonyms Rodol LY [Lowenstein Dyes Cosmetics http //www.Jhiowenstein.com] 4-Nitro-o-phenylenediamine CAS 99-56-9 EINECS/ELINCS 202-766-3 Synonyms 2-Amino-4-nitroaniline 1,2-Benzenediamine, 4-nitro- Cl 76020 1,2-Diamino-4-nitrobenzene 4-Nitro-1,2-benzenediamine... 

Rodol 4J. See 4-Nitro-o-phenylenediamine Rodol 1SN. See 1,5-Naphthalenediol Rodol 23N. See 2,3-Naphthalenediol Rodol 26PYR. See 2,6-Diaminopyridine Rodol 27N. See 2,7-Naphthalenediol Rodol BA. See 4-Methoxy-m-phenylenediamine Rodol BLFX. See Toluene-2,5-diamine sulfate Rodol Brown 2R. See 2-Nitro-p-phenylenediamine Rodol Brown SO. See 2-Chloro-p-phenylenediamine sulfate Rodol C. See Pyrocatechol Rodol CRS. See 4-Chlororesorcinol Rodol D. See p-Phenylenediamine Rodol DEMAP. See N,N-Diethyl-m-aminophenol Rodol DEMAPS. See N,N-Diethyl-m-aminophenol sulfate... 

Naphthalenediol 2,7-Naphthalenediol 4-Nitro-m-phenylenediamine 4-Nitro-o-phenylenediamine 4-Nitro-o-phenylenediamine HCI Toluene-2,5-diamine sulfate intermediate, oxo alcohols C14-16 alpha olefin intermediate, oxo chemicals Propylene... 

Ammonium molybdate (VI) Phosphomolybdic acid Selenious acid reagent, alpha-keto acids 4-Nitro-o-phenylenediamine reagent, aluminothermic processes Magnesium... 

Nitro-p-phenylenediamine 4-Nitro-m-phenylenediamine 4-N itro-o-pheny lenediam i ne C6H7N3O2 2CIH 4-Nitro-o-phenylenediamine HCI C6H7Na04... 

Yellow needles from MogCO.Aq. M.p. 180° (188°). Spar. soL cold EtOH, hot HjO. Cone, caustic alkalis —> 2 4-dinitrophenol. (NHg)gS —> 4-nitro-o-phenylenediamine + 2-nitro-p-phenylenediamine. Forms no salts. Acetyl see 2 4-Dinitroacetanilide. Diacetyl m.p. 112-13°. 

Nitro-o-phenylenediamine 2-Nitro-/ -phenylenediamine 4-Nitroquinoline-l-oxide (4-NQO)... 

Nitro-1,2-benzenediamine 4-Nitro-o-phenylenediamine C6H7N3O2 99-56-9 153.139 dk red nd (dilal) 199.5 s acid... 

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