Amines analytical reagents

Dinitrobenzenesulfenyl chloride is a versatile analytical reagent for the characterization of a wide variety of organic compounds, including alcohols, mercaptans, ketones, olefins, amines, aromatic compounds, olefin oxides, and hydroxysteroids. Review articles summarize these applications.9 10... 

Benzoyl chloride is used in the manufacture of benzoyl peroxide and dye intermediates, for acylation (introduction of the benzoyl group into alcohols, phenols and amines), and as an analytical reagent (Lewis, 1993 Budavari, 1996). 

The procedure described for the preparation of ethylenediamine-bisborane is general for the synthesis of amine-boranes and of borane adducts of other electron donors in which elements such as phosphorus and sulfur serve as the donor atom. In addition to the procedure used here for triphenylphosphine-borane, borane adducts of phosphines have been prepared by Analytical reagent grade (Mallinckrodt). 

Use Analytical reagent for active hydrogen atoms in organic compounds also to determine water, alcohols, and amines in inert solvents. 

Tertiary amines that also contain carboxylic acid groups form remarkably stable chelates with many metal ions. Gerold Schwarzenbach first recognized their potential as analytical reagents in 1945. Since this original work, investigators throughout the world have described applications of these compounds to the volumetric determination of most of the metals in the periodic table. 

N,N -Dimethyl-1,2-diphenylethylenediamine and related chiral diamines are not only useful chiral auxiliaries in asymmetric synthesis, but they have also found applications as analytical reagents. They allow the resolution and the determination of enantiomeric composition of aldehydes by formation of diastereomeric aminals.31 34 Combined with PCI3, they allow determination of the enantiomeric composition of alcohols, biphenols, thiols and amines.35 36 The diamine described here is used most extensively. 

Benzoin Oxime. 2-Hydroxy-l,2-diphenyiethanone Mime 2-hydroxy -2-phenylacetophenone oxime. C Hts-NOji mol wt 227.25. C 73.99%, H 5.76%, N 6.16%, O 14.08%. Two isomers occor a or anti and /S or syn. Both have been prepd from benzoin and hydroxyl amine hydrochloride. Prepn of a-form Werner, Detscheff, Ber. 38, 69 (1905) F. J. Welcher, Organic Analytical Reagents vol. Ill (Van Nosttand, New York, 1947) pp 239-251. Prepn of 3-form Werner, Detscheff, loc. cit, Configuration of a - and Worms Meisenheimer, Meis, Ber. 57, 289 (1924). 

The spirolactone fluorescamine (432) reacts with primary amines to form highly fluroescent products making it a useful analytical reagent for the fluorometric determination of primary amines <72JA5927>. Diphenylisobenzofuran (433) continues to be useful as a trap for singlet oxygen and reactive alkenes. An example is its reaction with cyclopropabenzene (434), which is postulated to... 

Amines such as amino acids, polyamines, catecholamines, and peptides exist in most of the biological samples. In general, amino groups are so reactive that chemical reactions with the analytical reagents proceed under fairly mild conditions, and the numerous reagents for amines have been developed and applied to the highly sensitive determination of a large variety of analytes. 

Rgure 3 The reaction scheme for DNS-Cl with amine and analytical reagents containing sulfonyl chloride group. 

An acyl chloride such as benzoyl chloride can react with secondary and primary amines and amino acids to form N-substituted benzamide derivatives. Analytical reagents used for precolumn derivatizations are p-nitrobenzene azobenzoyl chloride for LC-UV, o-acetylsalicyloyl chloride for LC-ECD, and 3,4-dihydro-6,7-dimethoxy-4-methyl-3-oxoquinoxa-line-2-carbonyl chloride (DMEQ-COCl) and 4-(4,5-diphenyl-lf/-imidazol-2-yl)benzoyl chloride (DIB-Cl) for LC-FL, respectively. Pentafluorobenzoyl chloride (PFBC) is used as an acylating reagent for GC with electron-capture detection (Figure 4). Many of those described above can also react with hydroxyl and phenol groups. 

Figure 4 Analytical reagents with acyl chloride for amines.

Chloroformates are useful analytical reagents for primary, secondary, and tertiary amines. The reaction of these reagents with amines can be performed easily, and the resultant carbamate derivatives are suitable for GC analysis. The carbamate derivatives obtained from primary and secondary amines are determined selectively and sensitively by GC-MS and -BCD. After dealkylation, tertiary amines are derivatized to carbamates in the same manner for primary and secondary amines. The carbamate derivatives obtained with pentafluorobenzyl chloro-formate are determined with high sensitivity by GC-ECD. Chloroformates also react with phenols, thiols, imidazoles, as well as amines. 

Hydroxy compoimds such as alcohols, carbohydrates, steroids, and phenols are known to play important physiological roles. Although many analytical reagents have been developed for determination of hydroxy compounds, some of them can be also applied to amines as described in the previous section (e.g., isocyanates, sulfonyl chlorides, acyl chlorides, halogenobenzofurazans, acyl amides, and chloroformates). The derivatization conditions for hydroxy compounds are relatively more drastic than those for amines. By using fairly different conditions from those for amino compounds. 

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