Di-and Polyketones

The sulfonation procedure was extended to acetylacetone (2,4-pentanedione, 77) which, on treatment with chlorosulfonic acid in dichloromethane, afforded the 

The product 78 resulted from preferential enolization of the carbonyl group involving the most reactive (acidic) 3-hydrogen atom consequently with this substrate, there was selective 3-sulfonation. 

Several -diketones are sulfonated by treatment with sulfur trioxide-dioxan, e.g. 1,3-indandione yields the 2-sulfonic acid. 2-Phenyl-1,3-indandione 79 reacts with acetyl sulfate or chlorosulfonic acid in dioxan or ether to give the 2-sulfonic acid 80 the reaction occurring via the enolic form of the diketone (Equation 31). On the other hand, when the diketone 79 was treated with chlorosulfonic acid in a non-polar solvent only the phenyl ring was sulfonated presumably because under these conditions enolization was not favoured. 

Polyketones can be sulfonated by reaction with chlorosulfonic acid the products are chemically reactive and are useful as strongly acidic esterification catalysts and ion-exchange resins. The sulfonation of ethylene-carbonyl copolymer was achieved by treatment of the substrate with chlorosulfonic acid in dichloroethane at 0 C.  

Substituted and unsubstituted aliphatic aldehydes react with the sulfur triox-ide-p5nidine complex (obtained by reaction of chlorosulfonic acid with pyridine) in boiling 1,2-dichloroethane to give good yields of the betaine salts 81 (Equation 

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The selective hydrogenation of dicarbonyl compounds involves the saturation of one of the keto groups to produce a ketol. The a-di- and polyketonic 2-74 compounds as well as acyloins 5,76 and polyhydroxyaldehydes, such as glyceraldehyde and the sugars,2.77,78 can be hydrogenated either selectively or completely to the polyhydroxy materials under mild reaction conditions. The... 

It is possible to produce polyketones by the reaction of aromatic di-carboxylic acid and aromatic compound containing two reactive groups [332]. The reaction is catalyzed by the mix of phosphoric acid and carboxylic acid anhydride having the formula of RC(0)0(0)CR (R stands for not-substituted or substituted alkyl, in which one, several or all hydrogen atoms were replaced by functional groups and each R has the Garnet constant o > 0.2). The pressed articles can be created from S5mthesized polyketones. 

Both of these types of polymers are made from inexpensive raw materials for the most part. The biphenylene di-carboxylic acid used in the polyketone is only needed to a very small extent of the total weight of the polymer, and is readily obtained by literature methods from common raw materials. Teh phenylacetylene substituted diphcnic acid used in the second polymer mentioned above is also available by straightforward reactions from relatively cheap raw materials and is only a minor component of the final resin. Thus, the new polymers should be capable of production at prices that will permit their general use. 

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