Hydrazine analytical

Hydrazide method, for covalent ligand immobilization, 6 396t Hydrazine, 70 727 73 562-607. See also Anhydrous hydrazine analytical methods for, 73 588-589 aqueous grades of, 73 585 chemical properties of, 73 566-576 as a corrosion inhibitor, 73 595 economic aspects of, 73 584-585 electrode potentials of, 73 566t explosive limits of, 73 566 handling and storage of, 73 586-588 as a hazardous material, 73 585... 

Figure 9 Reaction scheme for NPH with carboxylic acid and hydrazine analytical reagents.

Many of these compounds ate highly colored and have found use as dyes and photographic chemicals. Several pharmaceuticals and pesticides are members of this class. An extremely sensitive analytical method for low hydrazine concentrations is based on the formation of a colored azine. They are also useful in heterocycle formation. Several reviews are available covering the chemistry of hydrazones (80,89) and azines (90). 

As the result of the performed investigations was offered to make direct photometric determination of Nd microgram quantities in the presence of 500-fold and 1100-fold quantities of Mo and Pb correspondingly. The rare earth determination procedure involves sample dissolution in HCI, molybdenum reduction to Mo (V) by hydrazine and lead and Mo (V) masking by EDTA. The maximal colour development of Nd-arsenazo III complex was obtained at pH 2,7-2,8. The optimal condition of Nd determination that was established permit to estimate Nd without separation in solution after sample decomposition. Relative standard deviations at determination of 5-20 p.g of Nd from 0,1 g PbMoO are 0,1-0,03. The received data allow to use the offered procedure for solving of wide circle of analytical problems. 

Rondevstedt, C. S., Chem. Eng. News, 1977, 55(27), 38 Synthesis, 1977, 851-852 In an attempt to reduce 2-chloro-5-methylnitrobenzene to the aniline by treatment with excess hydrazine and Pd/C catalyst, the hydroxylamine was unexpectedly produced as major product. During isolation of the product, after removal of solvent it was heated to 120°C under vacuum and exploded fairly violently. Many aryl-hydroxylamines decompose violently when heated above 90-100°C, especially in presence of acids. GLC is not suitable as an analytical diagnostic for arylhydroxyl-amines because of this thermal decomposition. 

Hydrazine reduces potassium iodate in hydrochloric acid forming iodine monochloride, a reaction of analytical importance ... 

Hydrazine hydrate is used as a reducing agent in synthetic and analytical reactions and as a solvent for many inorganic compounds. It also is used with methanol as a propellant for rocket engines. Another apphcation is catalytic decomposition of hydrogen peroxide. 

Hydrazine sulfate is used as a reducing agent in analytical chemistry for gravimetric measurement of nickel, cobalt, and other metals, and in peptide analysis in the separation of polonium from tellurium as an antioxidant in... 

Analytical. Hydrazine content in aqueous solutions is determined by reacting with picryl chloride to form the yellow hexanitro hydrazobenzene, which, with alkali forms red or violet salts that can be measured colorimetrically (Ref 3). More concentrated solution of hydrazine can be titrated with either standard iodine or iodate solutions according to the following equations (Ref 4) ... 

Barlot and Medard (Refs 2 3) describe an analytical procedure for nickel nitrohydrazinate decompose the complex cautiously (to avoid an explosion) by means of coned H2S04 and determine Ni content by means of dimethylgly-oxime. Determine the hydrazine content by means of an iodate soln... 

In cases where peptides contained either aliphatic hydroxy (Ser or Thr) or carboxy groups (Asp or Glu, or free a-carboxy), a second deformylation procedure was employed 30 To the cyclic peptide analogous to 5 was added hydrazine monohydrate (99%, 5.4 mL, 111 mmol) in EtOH/H20/AcOH (55 35 10, 45 mL) with stirring. The mixture was kept at 37 °C for 16 h after which time completion of the deformylation was verified by analytical RP-HPLC. 

A sensor for organic chloride-containing compounds was constructed by immobilization of luminol or tris (2,2 bipyridyl) ruthenium (III) between a PMT and a poly (tetrafluoro) ethylene (PTFE) membrane [15], through which a stream of air was sampled by diffusion. A heated Pt filament incorporated in the gas line leading to the CL cell was used to oxidize the analytes prior to diffusion across the PTFE membrane. Detection limits for CC14, CHC13, and CH2C12 were 1.2-4 ppm. A similar device could also be used for the determination of hydrazine and its monomethyl and dimethyl derivatives or NH3 vapor. The detection limit for hydrazine was only 0.42 ppb [16]. 

Other molecules capable of serving as coreactants in this reaction type are aliphatic amines [26], amino acids [27-30], NAD(P)H [31], hydroxide ions [32], hydrazine [32], and NaBITt [32], although each reaction is different and there are variations in the mechanism of each analyte interacting with [(bpy)3Ru]2+. 

---