Acrolein dibromide

Aldol condensations analogous to the formose reaction have been utilized to synthesise mixtures of trioses, tetroses, pentoses, and hexoses from 3-oxo compounds. The same paper describes the synthesis of hexoses from barium hydroxide treatment of acrolein dibromide. 

Acrolein dibromide. See 2,3-Dibromopropionaldehyde Acroiex] Acronai DS 3429] Acronai DS 3458. See Acrylic resin... 

Synonyms Acrolein dibromide Dibromopropanal Dibromopropionaldehyde Propanal, 2,3-dibromo- Propionaldehyde, 2,3-dibromo-... 

Formaldehyde condenses in the presence of weak bases to form a complex mixture of sugars called formose or methose The polymerization undoubtedly proceeds through a combination of acyloin and aldol condensations. Fischer and Tafel 125) obtained a similar sugar mixture by the action of dilute alkali on acrolein dibromide. Presumably, the reaction sequence is the following (Chapter I) ... 

Fischer and Tafel s Complete Synthesis of Hexose Sugars a-ACROSE (from formaldehyde, glyceraldehyde, or acrolein dibromide) c H6NHNH2... 

After the discovery of methylenitan by Butlerow and formose by Loew, from formaldehyde (see p. 8zi), Fischer and TafeF prepared what they called a- and )S-acrose by the action of baryta water on acrolein dibromide CH2 CH-CH0 CH20H CHOH-CHO -> C3Ht20e. a-acrose was shown... 

When exposed to sunlight, it is converted to a white insoluble resin, disacryl. Oxidized by air to propenoic acid small amounts of hy-droquinone will inhibit this. Bromine forms a dibromide which is converted by barium hydroxide into DL-fructose. The acrid odour of burning fats is due to traces of propenal. It is used in the production of methionine and in controlled polymerization reactions to give acrolein polymers. ... 

Ethyl sec-amyl ketone, see 5-Methyl-3-heptanone Ethylbenzol, see Ethylbenzene Ethyl butyl ketone, see 3-Heptanone Ethyl n-butyl ketone, see 3-Heptanone Ethyl carbinol, see 1-Propanol Ethyl cellosolve, see 2-Ethoxyethanol Ethyl chloride, see Chloroethane Ethylcyclopentan, see Ethylcyclopentane Ethyldimethylmethane, see 2-Methylbutane Ethylendiamine, see Ethylenediamine Ethylene aldehyde, see Acrolein Ethylene bromide, see Ethylene dibromide Ethylene bromide glycol dibromide, see Ethylene dibromide... 

Methoxy-l-benzopyrans are prepared at or below room temperature from 2-bromophenols and 3-trimethylsilyloxyacroleins. Protection of the phenolic group and lithiation precede treatment with the acrolein when the protecting group is removed with cold mineral acid, cyclization occurs in good yield. Chalcone dibromides cyclize in a basic medium but yields of pyrans are often better under weakly basic conditions, as is demonstrated in this synthesis of a flavone in dilute alkali at room temperature. 

Toxic in contact with skin 3 Danger >200 to <1000 Acrolein, acrylamide, acrylonitrile, aniline, t-butylhydroperoxide, ethylene dibromide, formaldehyde, hydrogen peroxide, methyl iodide, phenol... 

To obtain a substituted vinyl group, acrolein acetal (11) was converted to the dibromide (12), which reacts with ethylldenetriphenylphosphorane or diethyl phenylthiomethyl-phosphonate to form (13) (eq 3). Treatment with f-butyllithium followed by HBr formed the monobromide and then reaction with f-butylllthlum produced (Im) or (Is). 

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