Ketones with water

Scheme 9.20 Ru-catalysed reductions of ketones with water-soluble analogues of Noyori s and Knochel s ligands.

Since at a high dilution of methyl ethyl ketone with water the experimental rate constants obtained do not depend on the amount of water, it may be considered that only R02. . . H20 radicals are present in the system under given conditions, and the results obtained represent the kn1 and k6n constants. 

Single Stage and Cross Current Extraction of Acetic Add from Methylisobutyl Ketone with Water... 

Figure 3-15. The formation of a hydrate (R = H) or a hemiacetal (R = alkyl or aryl) in the reaction of a ketone with water or an alcohol.

Fig. Intermolecular hydrogen bonding of a ketone with water.

An example of the reaction of aldehydes and ketones with water to form addition products called hydrates is illustrated in the following equation for the case of acetaldehyde ... 

POCI3 chlorinations (Eq. (8)) are acid-catalyzed reactions of such reaction products]. The hydrogen bonding of azinones is related to that of iV-oxides, discussed below, and to that of ketones (with water and alcohols) and has been demonstrated by infrared measurements on pjn-idinethione in alcohols and by the electronic absorption spectra of azinones in water. 6-Chloro-l,3-dimethyl-pyrimidine-2,4-dione is rapidly aminated at 20° (with heat evolution) by methyl- or ethyl-amines, etc., in protic media (water or alcohols). 

Single Stage and Cross Current Extraction of Acetic Acid from Methyliso utyl Ketone with Water The original mixture contains 35% acetic acid and 65% MIBK. It is charged at 100 kg/hr and extracted with water. 

Reaction of an aldehyde or a ketone with water forms a hydrate (Section 17.11). The mechanism is shown on page 818. 

This section and Sections 17-7 and 17-8 introduce the reactions of aldehydes and ketones with water and alcohols. These compounds attack the carbonyl group through the mechanisms just outlined, utilizing either acid or base catalysis. 

Activation by rhodium complexes has been used to achieve direct exchange of ketone methyl or aryl groups with an aryl group on ArB(OH)2, selective C(CO)-C bond cleavage on reaction of ketones with water, oxidative acylation between secondary benzamides and aryl aldehydes with subsequent intramolecular cyclization to 3-hydroxyisoindolin-l-ones, " cross dehydrogenative coupling to form xanthones from 2-aryloxybenzaldehydes, and activation of the aldehydic C-H bond to achieve hydroacylation of unactivated alkenes by salicylaldehyde derivatives and of vinylsilane by benzaldehyde. ... 

The exchange of aldehydes and ketones with water is fairly rapid as is seen from Table VI. This exchange is both acid and base catalyzed (Cohn and Urey, 1938). 

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