Ethylenediamine dihydrochloride, reaction

Nitrite can be deterrnined by reaction with sulfanilamide to form the diazo compound, which couples with /V-(1-naphthyl)ethylenediamine dihydrochloride to form an intensely colored red azo dye. Nitrate can be deterrnined in a similar manner after reduction to nitrite. Suitable reducing agents are cadmium filings or hydrazine. This method is useful at a nitrogen concentration of 10 -lO " M. 

Spray solution Ilb Dissolve 1 g 7V-(l-naphthyl)ethylenediamine dihydrochloride in 50 ml dimethylformamide and 50 ml hydrochloric acid (< Hci = 4 mol/1) with warming. If the cooled solution is not clear it should be filtered. A pale violet coloration does not interfere with the reaction [4]. 

Titanium(III) chloride (particularly in slightly alkaline medium) reduces the p-nitro groups of the thiophosphate insecticides to amino groups, which are then reacted with nitrite in acid mediiun in a second step to yield a diazonium compound as intermediate. This is then coupled to N-(l-naphthyl)-ethylenediamine dihydrochloride to yield an azo dye [3]. In the case of benzodiazepines the first reaction step includes an additional acid hydrolysis to the corresponding benzophenone derivative [2]. 

E.K.C. 4835 is N-(l -naphthylj-ethylenediamine dihydrochloride. Recent chromatographic evidence indicates that the final colored reaction product from technical grade parathion may be a mixture of at least three and possibly four components. 

An alternative method for the preparation of the dihydrodiazepinium salt 5 involves the reaction of ethylenediamine dihydrochloride with ace-tylacetone [67JCS(C)2400]. Dihydrodiazepines have also been obtained from reactions between diketones and ethylenediamine (free base) in ethanol (71 Mil 78JIC577 78MI1). 

The benzoic acid and ethylenediamine dihydrochloride isolated after the cited reaction time amount to ca. 90%. 

Osmium tetraoxide, an expensive and toxic1 reagent, is reduced safely and quantitatively by ethanol in potassium hydroxide solution to form K2 [0s02 (OH)4]. 2 Subsequent reaction in aqueous solution with excess ethylenediamine dihydrochloride affords, in very good yield, the salt /rans-[0s02(en)2 ] Cl2.3 Both these compounds are relatively stable and can be handled easily. Furthermore, they are useful starting materials for subsequent syntheses.3 4... 

Fig. 7.18. Low-pressure interfaces to detectors based on flow injection. (A) Interface to a photometric detector across a membrane. (Reproduced with permission of the American Chemical Society.) (B) Interface to a flow-through photometric sensor with prior derivatization by the modified Griess reaction. (Reproduced with permission of the American Chemical Society.) (C) Interface to a piezoelectric detector. P peristaltic pump, C collector, CUC clean-up column, DB debubbler, SA sulfamic acid, NEDD /V-( 1-naphthyl)ethylenediamine dihydrochloride, SV switching valve, W waste, DF displacement flask, IV injection valve, FC-PZ flow-cell-piezoelectric crystal, OC oscillator circuitry, F frequency counter, PC personal computer. (Reproduced with permission of Elsevier.)...

Boyd EM, Seymour KGW. 1946. Ethylenediamine dihydrochloride or chlor-ethamine. II. Untoward and toxic reactions. Exp Med Surg 223-227. 

The cis and trans forms of dichlorobis(ethylenediamine)-rhodium(III) nitrate are obtained from solutions of the corresponding chlorides by reaction with concentrated nitric acid. Solutions of the chlorides are prepared from hydrated rhodium(III) chloride by treatment with ethylenediamine dihydrochloride, the hydrochloric acid set free being neutralized with potassium hydroxide in such a manner that no excess base is ever present. ... 

This has been implemented by making use of the MCFIA flow system shown in Figure 7.47 based on absorbance measurement of the azo dye obtained by the reaction of nitrite with iV-(l-naphthyl) ethylenediamine dihydrochloride and sulfanilamide. Nitrate was reduced to nitrite in a copperized cadmium column while the modified Berthelot s reaction (indophenol blue reaction) with salicylate... 

Twelve carbamate, urea, and anilide herbicides investigated in water and soil samples were detected with Bratton-Marshall reagent after separation on KC g reversed-phase TLC plates. These pesticides produce aromatic amines after acidic hydrolysis. These primary aromatic amines could be diazotized and detected by azo-coupling reactions giving azo-dyes. After develc ment plates were sprayed with 6 N ethanolic HCl and heated at 180 C for 10 min. After cooling they were sprayed with NaN02 solution and later with AM-naphthyl-ethylenediamine dihydrochloride solution. The colored spots were evaluated by densitometry at nanogram levels (147). 

Barbiturates in micro amounts determined by shift in spectrum going from pH 10.5 to strongly alkaline determined in extracts from blood at 260 m in 1 AT NaOH before and after addition of ethylenediamine dihydrochloride Chloral hydrate in admixture with trichloroacetic acid and trichloroethanol used reaction with pyridine Strychnine (252 m/i) mixed with brucine (262 m ) [ ]. Theobromine and caffeine in cocoa powders (after separa-tion)[ ]. 

The reaction mixture of ethylenediamine and glycolonitrile (HOCH2CN) when treated with an excess amount of hydroxylamine in methanol gave 2-hydroxyimino-piperazine (1614) [which with 3N hydrochloric acid and methanol afforded the dihydrochloride of A -(2 -aminoethyl)glycine methyl ester] (1614). 

This compound, 223, a potent and selective iXj-adrenoceptor agonist used also in studies of vasoconstriction , has been obtained according to the reaction sequence of equation 93. This involves oxidation of high-specific-activity paraldehyde-with selenous acid to ethanedial-l,2- C2 which was condensed directly with 1,2,4-benzenetriamine dihydrochloride to 6-quinoxalin-2,3- C2-amine in 56% yield, bromi-nation of 224 and conversion of 225 to its isocyanate 226 by reaction with thiophosgene, and finally the reaction of 226 with ethylenediamine in refluxing 1 1 methanol-toluene. The overall radiochemical yield of 223 was 11% starting from paraldehyde-The radiochemical purity of the tartrate 227 was 98.2%, specific activity 101.5 mCi mmor ... 

The enzyme/substrate (tyrosinase/wool hydrolysate) mixture (20 pL) was diluted widi 980 pL of distilled water, 70 pL of ethylenediamine, and 50 pL of 2M etfaylenediainine dihydrochloride (pH 11). The mixture was incubated at 50°C for 2 h in die dark, and then the fluorescence intensity was measured using a UVA IS spectrofluorom o (Tecan). The excitation and emission wavelengdis were at 420 and 543 nm, respectively. The concentrations of the DOPA residue in the preparations were estimated using a standard fluorescence curve of DOPA [8]. For the Dopa Quinone (DQ) quantification M6TH (3-methyl-2-benzothiazolinone hydrazone hydrochlcnide monohydrate) was used. MBTH reacts with DQ to form a pink pigmoit widi Xnm at 505 nm. The assay solution was prepared by mixing 480 pL of the en me/substrate reaction mixture, 980 pL of 4.3% (v/v) DMF (dimethyl formamide) in distiUed water, and 580 pL of 20.7 mM MBTH. The total volume was 2 mL. Tbe reacticm mixture was incubated at 25 C for 10 min before the absorbance measurement (at 505 nm) [8]. 

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