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A-lodination

V. SULFONYL HALIDES AS SYNTHONS A. lodination of Sulfonyl Chlorides... [Pg.417]

Silylation. Transsilylation from a < lodination of the double bond, rendering 1 as 2-iodomethyltetrahydrofuran). [Pg.48]

Jprgensen et al. and Macmillan et al. independently reported on the successful enantioselective a-chlorination and a-bromination of carbonyl groups using amino catalysts. a-lodination remained unsolved until the recent discovery of the binol-derived catalysts by Maruoka et A general catalytic cycle, involving an enamine... [Pg.1293]

A positive value for A/7° signifies an endothermic re action The reactants are more stable than the prod ucts and so lodination of alkanes is not a feasible reaction You would not want to attempt the prepa ration of lodomethane by lodination of methane... [Pg.174]

J a lodo acids are not normally prepared by direct lodination of... [Pg.816]

Cinnolin-4(lF/)-one and its 6-chloro, 6-bromo, 6-nitro and 8-nitro derivatives react with sulfuryl chloride or bromine in acetic acid to give the corresponding 3-halo derivatives in about 20% yields. lodination of 8-hydroxycinnolin-4(lF/)-one with a mixture of potassium iodide and potassium iodate gives the 5,7-diiodo derivative the 6,8-diiodo derivative is formed from 5-hydroxycinnolin-4(lF/)-one. [Pg.21]

GAREGG - SAMUELSSON Olefin Synthesis Conversion of vie Irans-dwl groups into a double bond by lodine-lnphenylphosphine-imidazole reagent. [Pg.141]

HASSNER -RUBOTTOM a-Hydroxytation a-Hydroxyiatlon, lodination, or oximation of carbonyls via silyl snol ethers. [Pg.160]

In all countries with developed medical care, X-ray contrast media can be expected to be present at appreciable quantities in sewage water. Clara et al [13] detected iopromide at a mean concentration of 3.84 pg in the influent of a WWTP receiving hospital wastewater, while in WWTPs without a hospital within their drainage area this contrast media was not present. lodinated X-ray contrast media are proved to contribute significantly to total absorbable organic iodine in clinical wastewaters up to 130 pg of iodine in the influent of municipal WWTP in Berlin and 10 mg in hospital sewage was detected [23]. [Pg.202]

Cao XY, Jiang XM, Kareem A, Don ZH, Rakeman MA, Zhang ML, Ma T, O Donnell K, DeLong N, DeLong GR. 1994. lodination of irrigation water as a method of supplying iodine to a severely iodine-deficient population in Xinjiang, China. Lancet 344 107-110. [Pg.262]

Following a similar strategy, an ingenious mixed resin bed quench and purification strategy was devised for the Dess-Martin periodinane mediated conversion of alcohols to carbonyls. This hypervalent iodine oxidant was viewed as containing an inherent masked carboxylic acid functionality that was revealed at the end of the reaction (Species (11) Scheme 2.30). Therefore purification was easily achieved by treatment of the reaction mixture with a mixed-resin bed containing both a thiosulfate resin and a polymeric base. The thiosulfate polymer was used to reduce excess hypervalent iodine lodine(V) and (III) oxidation states species to 2-iodoben-zoic acid (11), which was in turn scavenged by the polymeric base [51]. [Pg.74]

Most contrast agents elicit nephrotoxicity because they are primarily excreted by the kidneys. However, when administered in small doses, they constitute a rich source of GFR markers. The two major classes of contrast agents that are finding clinical utility as GFR markers are iodinated aromatic compounds and metal complexes. lodinated aromatics such as iohexol and iothalamate (Fig. 13) are commonly used as contrast agents for computed tomography (GT). They also have pharmacokinetics similar to inulin and hence are useful indicators of renal status [215]. The iodinated molecules used for GFR measurements consist of a triiodo-benzene core and hydrophilic groups to enhance solubility in aqueous medium. [Pg.56]

We describe a new series of monodisperse, macromolecular lodinated contrast agents. The synthesis, analysis and pharmacokinetics of these molecules are presented. [Pg.151]

Molecular iodine is oxidised in acetonitrile at about the same potential as alkyl iodides. It forms iodine(l), co-ordinated with one molecule of acetonitrile [18]. lodine(l) will oxidise alkyl iodides to form a carbonium ion and molecular iodine. Thus the iodine generated during electrochemical oxidation of an alkyl iodide can function as an electron transfer agent in the latter stages of reaction [19]. [Pg.33]

Sigler, P. B. (1970). lodination of a single tyrosine in crystals of alpha-chymotrypsin. Biochem. 9,3609. [Pg.95]

Crich and Rumthao reported a new synthesis of carbazomycin B using a benzeneselenol-catalyzed, stannane-mediated addition of an aryl radical to the functionalized iodocarbamate 835, followed by cyclization and dehydrogenative aromatization (622). The iodocarbamate 835 required for the key radical reaction was obtained from the nitrophenol 784 (609) (see Scheme 5.85). lodination of 784, followed by acetylation, afforded 3,4-dimethyl-6-iodo-2-methoxy-5-nitrophenyl acetate 834. Reduction of 834 with iron and ferric chloride in acetic acid, followed by reaction with methyl chloroformate, led to the iodocarbamate 835. Reaction of 835 and diphenyl diselenide in refluxing benzene with tributyltin hydride and azobisisobutyronitrile (AIBN) gave the adduct 836 in 40% yield, along with 8% of the recovered substrate and 12% of the deiodinated carbamate 837. Treatment of 836 with phenylselenenyl bromide in dichloromethane afforded the phenylselenenyltetrahydrocarbazole 838. Oxidative... [Pg.254]

Stille cross-coupling and reductive N-heteroannulation steps. lodination of 1033, followed by Stille cross-coupling of the corresponding iodo derivative 1034 with the arylstannane 1035, gave the annotation precursor 1036. Reductive N-heteroannula-tion of 1036 afforded the carbazolone 1001, which was previously (99) (see Scheme 5.143) used to prepare clausenalene (90) via a Wolff-Kishner reduction followed by aromatization (659) (Scheme 5.155). [Pg.290]

Bromine bromate, 0276 Bromine dioxide, 0258 Bromine perchlorate, 0235 Bromine trioxide, 0259 Bromyl fluoride, 0239 Chlorine dioxide, 4042 Chlorine perchlorate, 4101 Chlorine trifluoride oxide, 3982 Chlorine trioxide, 4044 Chloiyl hypofluorite, 3973 Chloiyl perchlorate, 4104 Dichlorine oxide, 4095 Dichlorine trioxide, 4100 Dicyanogen Ai,A -dioxide, 0998 Dioxygen difluoride, 4320 Fluorine perchlorate, 3976 Hexaoxygen difluoride, 4327 Iodine dioxide trifluoride, 4334 lodine(V) oxide, 4627 lodine(VII) oxide, 4628 Oxygen difluoride, 4317 Perbromyl fluoride, 0240 Perchloryl fluoride, 3974... [Pg.166]

Ethoxy-l-iodo-3-butene, 2449 Hexamethylenetetramine tetraiodide, 2471 (Hydroxy)(oxo)(phenyl)-A, -iodanimn perchlorate, 2299 lodinated poly(sulfur nitride), 4622... [Pg.188]

A -Fluoroiminosulfur tetrafluoride, 4357 5-Hydrazino-1,2,3,4-thiatriazole, 0462 lodinated poly(sulfur nitride), 4622 Mercury (I) thionitrosylate, 4610... [Pg.272]

Indomethacin (Indocin) is an acetic acid derivative related functionally to sulindac (Clinoril), a prodrug with a long half-life, and etodolac (Lodine). They are metabolized in the liver and excreted as metabolites in the... [Pg.314]


See other pages where A-lodination is mentioned: [Pg.52]    [Pg.448]    [Pg.233]    [Pg.153]    [Pg.402]    [Pg.404]    [Pg.238]    [Pg.141]    [Pg.52]    [Pg.448]    [Pg.233]    [Pg.153]    [Pg.402]    [Pg.404]    [Pg.238]    [Pg.141]    [Pg.438]    [Pg.579]    [Pg.207]    [Pg.952]    [Pg.1139]    [Pg.293]    [Pg.89]    [Pg.11]    [Pg.120]    [Pg.190]    [Pg.267]    [Pg.386]    [Pg.26]    [Pg.26]    [Pg.698]    [Pg.284]    [Pg.99]    [Pg.120]    [Pg.332]    [Pg.353]   
See also in sourсe #XX -- [ Pg.153 ]




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