Aldehydes reductive iodination using

Reduction to Halocarbons. The best conditions for the reductive chlorination of ketones use the reagent combination Me2ClSiH/In(OH)3 (Eq. 241).331 Examples include conversions of aryl ketones to benzyl chlorides, ethynyl ketones to propargyl chlorides, and alkyl ketones to alkyl chlorides (Eq. 242).331 Addition of lithium iodide to the reaction mixture yields the corresponding iodide product. The combination of TMDO/I2 reductively iodinates aryl ketones and aldehydes in good yields (Eq. 243).357... 

Ana.lytica.1 Methods. Various analytical methods involve titration with oxidants, eg, hexacyanoferrate (ferricyanide), which oxidize dithionites to sulfite. lodimetric titration to sulfate in the presence of formaldehyde enables dithionite to be distinguished from sulfite because aldehyde adducts of sulfite are not oxidized by iodine. Reductive bleaching of dyes can be used to determine dithionite, the extent of reduction being deterrnined photometrically. Methods for determining mixtures of dithionite, sulfite, and thiosulfates have been reviewed (365). Analysis of dithionite particularly for thiosulfate, a frequent and undesirable impurity, can be done easily by Hquid chromatography (366). 

Hydrolysis of the 1,3-oxathiane moiety has been accomplished under mild conditions (0°C, 5 min) by the use of N-Chlorosuccinimide-Silver(l) Nitrate. This oxidative hydrolysis produces a-hydroxy aldehydes in good yields and, in addition, two diastereomeric sultines (19) (eq 8). The use of Iodine-for the oxidative hydrolysis of 1,3-oxathianes has also recently been reported. The tertiary a-hydroxy aldehydes are easily oxidized directly to the acids (Sodium Chlorite) or methyl esters (MeOH, I2, KOH) or are conveniently reduced to the diols by direct reduction of the hydrolysis mixture with Sodium Borohydride. The secondary a-hydroxy aldehydes could likewise be reduced to the glycols without racemization however, oxidation required pro-... 

Use Reduction of various organic compounds purification of aldehydes and ketones, iodine, sodium hydrosulfite antiseptic source of sulfurous acid, particularly in brewing analytical chemistry tanning bleaching straw and textile fibers chemical preservative in foods (except meats and other sources of vitamin B,). 

Oxidation of an aldehyde group to a carboxyl group has often been used for identification of the compounds. As far as can be judged from the results, such oxidations, using chromium trioxide/acetic acid, bromine-water, - peroxy acids, - or chlorite, have not been accompanied by any important side-reactions. Hypoiodite titration, using the iodine in sodium bicarbonate-sodium carbonate procedure, has sometimes been used, giving almost stoichiometric aldehyde determinations. - - Reduction by the Meerwein-Ponndorf reaction, with borohydride - - ... 

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