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Iodine-azide reagent

Kudzin ZH, Kotynski A, Kielbasinski P. 1991. Application of the iodine-azide reagent for selective detection of thiophosphoryl compounds in thin-layer chromatography. J Chromatogr 588 307-313. [Pg.199]

Mix a drop of the test solution and a drop of the iodine-azide reagent on a watch glass. A vigorous evolution of bubbles (nitrogen) ensues. [Pg.307]

Thiosulphates and thiocyanates act similarly and must therefore be absent. The sulphide can, however, be separated by precipitation with zinc or cadmium carbonate. The precipitated sulphide may then be introduced, say, at the end of a platinum wire into a semimicro test-tube or centrifuge tube containing the iodine-azide reagent, when the evolution of nitrogen will be seen. [Pg.310]

There are numerous methods for sulfur(II) detection in thin-layer chromatography (TLC). Most of them are based on general, rather than specific, techniques. The iodine-azide reaction takes place only in the presence of a sulfur(II) compound (selective induction), and only these compounds are visible on the thin-layer plate after treating with an iodine-azide reagent. The detection limits are as low as a picomol per spot. The factors that have an impact on the detection limits are discussed in this entry. The developed method has been applied to detect various thiols in biological samples (urine and blood serum), pesticides, and dmgs. [Pg.1226]

Kotynski, A. Kudzin, Z.H. Okmszek, A. Krajewska, D. Olesiak, M. Sierzchala, A. Iodine-azide reagent in detection of thiophosphoryl nucleotides in thin-layer chromatography systems. J. Chromatogr. A, 1997, 773, 285-290. [Pg.1233]

A postcolumn detection system based on the reaction between azide ions and iodine, induced by sulfur(II) compounds, is presented. The method involves separation of sulfur(II) compounds using varied chromatographic systems, followed by spectrophotometric measurement of the residual iodine from the postcolumn reaction after mixing with the iodine-azide reagent. The obtained chromatograms show a negative peak as a result of the decrease in background absorbance. Various factors that have an impact on the determination of sulfur(II) compounds are discussed. [Pg.1234]

Procedure. A few milligrams of the solid and a particle of metallic potassium are placed in a capillary tube and heated until the jwtassium melts. The tube is then heated strongly and the hot capillary is dropped into a micro test tube containing a few drops of water. A drop of cadmium chloride solution is added, the mixture is acidified with acetic acid, and iodine-azide reagent is introduced. In the presence of sulfide (implying sulfate in the original sample) nitrogen bubbles appear. [Pg.595]

Each TLC plate was spread consecutively with the following reagents (a) 2N sodium hydroxide (b) the iodine-azide reagent of Awe et al., Naturwissenschaften, 41 (1954) 528 (c) 1% starch soln. [Pg.99]

Iodine-azide soln. Dissolve I g sodium azide in a mixture of 10 ml 0.1 M iodine soln. and 90 ml water. Starch soln. 0.5% soln. of soluble starch. Dry in air and spray well with starch soln. Finally dry with warm air and spray with iodine-azide reagent repeat this alternate drying and spraying with iodine-azide until the white spots are distinct (2-3 times)... [Pg.288]

Iodine azide is a highly selective reagent addition to the 16-double bond of androsta-4,16-diene-3-ones is possible and some selectivity in addition to the 16-double bond of A -dienes has been observed.Hydroxy groups in the steroid should be protected, e.g., by acetylation, since in some instances oxidized side products are formed. [Pg.24]

Ridomil, with which the treatment with starch solution was not carried out, is said to yield brown chromatogram zones on a pale yellow background [14]. Hence, it may be assumed that this detection is based not on the iodine azide reaction but on the physical adsorption and enrichment of iodine in the lipophilic chromatogram zones (cf. Iodine Reagents ). [Pg.159]

The isolated solid is a very shock- and friction-sensitive explosive [1], but the preparation and safe handling of dilute solutions in solvents other than ether have been described [2], The need to use appropriate techniques and precautions when using iodine azide as a reagent is stressed [3], The purer the more explosive explosive properties are characterised (lead-block test, etc.) in a footnote to [4],... [Pg.1713]

Significant amounts of the bicyclo[3.3.1]nonane adduct and of the octahydropental-enes were isolated also from the reaction of 3 with preformed iodine acetate and iodine acetate thallium (equation 75)94 whereas only the monocyclic 1,2-adducts were obtained from treatment of 3 with iodine azide, iodine isocyanate or iodine nitrate95. The different propensity to give transannular products with these latter reagents has been related to the different positive charge density on carbons in the corresponding iodonium ion intermediates. [Pg.591]

A hypervalent iodine(III) reagent, Ph—1=0, together with TMS-azide, promotes direct a-azidation of cyclic sulfides the reaction opens up a route to unstable N,S-acetals. ... [Pg.3]

In the case of electrophilic addition, the reactions of tricyclic dienes 1 with several electrophilic reagents have been investigated.1 7 Interestingly, some of these compounds undergo addition reactions with remarkable syn stereoselectivity. For example, the reaction of dimethyl tricy-clo[4.2.2.02,5]deca-3,9-diene-7,8-dicarboxylate with iodine azide solution, prepared in situ from an excess of sodium azide and iodine monochloride, in acetonitrile at — 5 C provided the. yyn-4-azido-3-iodo derivative 2 (Table 1) in 90% yield.1,2,4,6 The formation of the 5,>,n-4-azido-3-iodo derivative 2 is thought to be the first example of a syn addition of iodine azide to an alkene.1,2 The formation of the syn-product is best explained by the twist strain theory,8 according to which the syn transition structure A is favored over the an/7-coplanar transition structure B.1... [Pg.29]

Imino thioethers,2 The reagent, prepared in situ, converts the dimethyl thioketal of a cyclic ketone (2) into the imino thioether 3 in high yield. The reaction can also he carried out with azidotrimethylsilane (1 equivalent), stannic chloride (1 equivalent), and iodine (10 mole %). but yields arc lower. This reaction was examined because of the reaction of thiokctals with iodine azide (this volume). [Pg.120]

LACTAMS Di-n-butyltin oxide. Ily-droxylamine-O-sulfonic acid. Iodine azide. Sodium eyanoborohydride. (3-LAC TAMS Cyanuric chloride. Grignard reagents. Ion-exchange resins. Lithium phenylethynolate. Sodium dicarbonyl-cyclopentadienylferrate. Titanium(lll) chloride. Titanium(IV) chloride. Tri-phenylphosphino-Carbon tetrachloride. Triphenylphosphine-Die thyl azodicar-boxylate. Triphenylphosphine-2,2 -Dipyridyl disulfide. [Pg.475]


See other pages where Iodine-azide reagent is mentioned: [Pg.477]    [Pg.155]    [Pg.236]    [Pg.777]    [Pg.404]    [Pg.435]    [Pg.477]    [Pg.155]    [Pg.236]    [Pg.777]    [Pg.404]    [Pg.435]    [Pg.84]    [Pg.87]    [Pg.82]    [Pg.22]    [Pg.15]    [Pg.50]    [Pg.158]    [Pg.49]    [Pg.785]    [Pg.893]    [Pg.113]    [Pg.273]    [Pg.84]    [Pg.607]   
See also in sourсe #XX -- [ Pg.84 , Pg.435 , Pg.437 , Pg.442 , Pg.453 , Pg.454 , Pg.463 , Pg.590 , Pg.591 , Pg.595 , Pg.610 ]




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Azide reagent

Iodinating reagents

Iodination Reagents

Iodination reagents iodine azide, addition

Iodine azide

Iodine azide, as reagent

Reagents iodine

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