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Iodine compounds, systematics

On the other hand, if one were interested in the medicinal uses of iodine and its compounds, it would be necessary to carry out quite a different kind of search, for the use of such iodine compounds undoubtedly carries back to a time long preceding the discovery of the element itself indeed, it appears that the ancient Assyrians used crude iodide preparations for medicinal purposes, and since these early days the ashes of sponges and kelps have been systematically so used. [Pg.85]

The periodinane (10) may also be prepared from o-iodobenzoic acid by oxidation with potassium bromate and then treatment with acetic anhydride18 (see Expt 6.36 for detailed formulation). It should be noted that the organic derivatives of pentacoordinate iodine(v) are termed periodinanes.18b This compound (the systematic name is l,l,l-triacetoxy-2,l-benzoxiodol-3(3//)-one) has found use as an oxidant of primary alcohols to aldehydes and alicyclic ketones to secondary alcohols it is claimed to have advantages over the chromium-based oxidation reagents. [Pg.869]

A systematic study of substitution reactions of oxazole itself has not been reported. Bromination of 2-methyl-4-phenyloxazole or 4-methyl-2-phenyloxazole with either bromine or NBS gave in each case the 5-bromo derivative, while 2-methyl-5-phenyloxazole was brominated at C(4). Mercuration of oxazoles with mercury(II) acetate in acetic acid likewise occurs at C(4) or C(5), depending on which position is unsubstituted 4,5-di-phenyloxazole yields the 2-acetoxymercurio derivative. These mercury compounds react with bromine or iodine to afford the corresponding halogenooxazoles in an electrophilic replacement reaction (81JHC885). Vilsmeier-Haack formylation of 5-methyl-2-phenyloxazole with the DMF-phosphoryl chloride complex yields the 4-aldehyde. [Pg.190]

The rather low semi-conducting behavior of [PcFeL] compounds (L = pyz, dib) can be increased not only by oxidative doping with iodine as reported earlier [5] systematic investigations on electrochemical doping processes are carried o t. As an example electrochemical doping of [PcFe(pyz)] 2 10 ) with a variety of counterions BF, ... [Pg.177]

Henrich developed a comprehensive TLC method for identification of surfactants in formulations (4). She specified two reversed-phase and four normal phase systems, with detection by fluorescence quenching, pinacryptol yellow and rhodamine B, and iodine. Prior to visualization, one plate was scanned with a densitometer at 254 nm, and UV reflectance spectra were recorded for each spot detected. Tables were prepared showing the Rf values of 150 standard surfactants in each of the six systems, along with the reflectance spectra and response to the visualizers. This system allows for systematic identification of compounds of a number of surfactant types (LAS, alcohol sulfates and ether sulfates, alkane sulfonates, sufosuccinate esters, phosphate compounds, AE, APE, ethoxylated sorbi-tan esters, mono- and dialkanolamides, EO/PO copolymers, amine oxides, quaternary amines, amphoterics and miscellaneous compounds). Supplementary analysis by normal phase HPLC aided in exactly characterizing ethoxylated compounds. For confirmation, the separated spots may be scraped from one of the silica gel plates and the surfactant extracted from the silica with methanol and identified by IR spectroscopy. [Pg.132]


See other pages where Iodine compounds, systematics is mentioned: [Pg.2]    [Pg.682]    [Pg.11]    [Pg.233]    [Pg.2]    [Pg.117]    [Pg.263]    [Pg.1163]    [Pg.29]    [Pg.198]    [Pg.172]    [Pg.161]    [Pg.861]    [Pg.232]    [Pg.263]    [Pg.18]    [Pg.238]    [Pg.58]    [Pg.93]    [Pg.570]    [Pg.697]    [Pg.152]    [Pg.161]    [Pg.22]    [Pg.199]    [Pg.28]    [Pg.49]    [Pg.115]    [Pg.52]    [Pg.102]    [Pg.107]    [Pg.472]   
See also in sourсe #XX -- [ Pg.467 , Pg.468 ]




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Iodinated compounds

Iodine compounds

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