Reactions with Ketone Reagents

A wide variety of substituted isatins have reacted with hydroxyl-amine to give isatin-3-oximes (72).6,26,42,51,92,107,126,169 274 O-Substi-tuted hydroxylamines also give this reaction.275 5-Bromoisatin-3-oxime 

Isatin-3-oximes readily form complexes with a variety of metal ions.278,279 In a number of cases, these have seen analytical applications.6,42,280-283 Isatin-2-oximes1 also form metal complexes.279,284-287 

Reduction of isatin-3-oximes to the corresponding 3-aminooxindole has been carried out using stannous chloride in acetic acid51 or in hydrochloric acid.92 3-Aminooxindole has also been obtained by electrochemical reduction288 and catalytic hydrogenation.169 Reduction 

Isatin-3-oxime reacts with isocyanates to give carbamoyloximino-isatins (75).290 Irradiation of AT-inethylisatin-3-oxime causes syn-anti isomerization,291 while A -acetylindazolone is obtained from irradiation of AT-acetylisatindioxime.291 Treatment of this dioxime with acetic 

Izquierdo and U. Rauret, Inform. Quim. Anal. 23, 161 (1969) Chem. Abstr. 72, 128318(1970). 

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Section 20 20 Nitriles are useful starting materials for the preparation of ketones by reaction with Grignard reagents... 

Grignard reagents undergo a general and very useful reaction with ketones. Melhylmagnesium bromide, for example, reacts with cyclohexanone to yield a product with the formula C7HuO. What is the structure of this product if it has an IR absorption at 3400 cm-1 ... 

The reduction of carbonyl compounds by reaction with hydride reagents (H -) and the Grignard addition by reaction with organomagnesium halides (R - +MgBr) are examples of nucleophilic carbonyl addition reactions. What analogous product do you think might result from reaction of cyanide ion with a ketone ... 

Nitriles are similar in some respects to carboxylic acids and are prepared either by SN2 reaction of an alkyl halide with cyanide ion or by dehydration of an amide. Nitriles undergo nucleophilic addition to the polar C=N bond in the same way that carbonyl compounds do. The most important reactions of nitriles are their hydrolysis to carboxylic acids, reduction to primary amines, and reaction with organometallic reagents to yield ketones. 

Vilstneier reagent, reaction with ketones to form 0-chloro-a,/3- unsaturated aldehydes, 46,19... 

It has long been known that a, l -unsaturated sulfones resemble a, l -unsaturated ketones and aldehydes in undergoing addition reactions with nucleophilic reagents. These reactions are initiated by nucleophilic attack at the carbon jS to the sulfone group ... 

When the carbonyl carbon is substituted with a potential leaving group, the tetrahedral adduct can break down to regenerate a C=0 bond and a second addition step can occur. Esters, for example are usually converted to tertiary alcohols, rather than ketones, in reactions with Grignard reagents. 

Amides, especially of piperidine and morpholine, give good yields of ketones on reaction with organocerium reagents.203 It has been suggested that the morpholine oxygen may interact with the oxyphilic cerium to stabilize the addition intermediate. 

House and Trafkante suggested that magnesium alkoxides promote deprotonation of ketones in the reaction with Grignard reagents leading to by-products. See Reference 18(a). 

Double-bond compounds between heavier group 14 and 16 elements (heavy ketones) undergo ready addition reactions with various reagents to give the corresponding single-bond compounds. The details of the reactivities are described in the next section (Schemes 20 and 21). 

It should be noted that, on reaction with Grignard reagents, aldehydes will produce secondary alcohols, whereas ketones will form tertiary alcohols. Often forgotten is the possibility of synthesizing primary alcohols by using formaldehyde as the substrate. 

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