Oximes, reaction with Raney nickel

By means of this reaction Caldwell and Jones (103) obtained citronell-amide in 50% yield when 20 g. of citronellaldoxime and 3 g. of Raney nickel were heated at 100-105° for 2 hours, and, after dilution with ether, the catalyst was removed by filtration through activated alumina. The oxime of tetrahydrocitral, when heated for 2 hours at 110-120° with Raney nickel, gave a 70 % yield of the amide of 2,6-dimethyloctanoic acid. 

Cycloheptanone oxime can be converted into the amine in good yield by high-pressure hydrogenation of the oxime with Raney nickel and ammonia, but Freifelder " found that the reaction is so strongly exothermal that on a large scale it may get out of hand. He then found that the hydrogenation can be accomplished smoothly by low-pressure hydrogenation in the presence of rhodium-alumina. The temperature was allowed to rise spontaneously to 60° and kept there until reduction... 

Hydrogenation of a,6-unsaturated aldehydes on Raney zinc catalysts was studied. Saturated aldehydes were obtained along with saturated alcohols. The amounts of each were dependent on reaction conditions. On reduction of nitriles and oximes with Raney alloy improved yields of primary amines were obtained. Treatment of ketoximes with Raney-nickel yields the ketones. 

A solution of 151 grams of 1-(3, 4 -dimethoxyphenyl)-2-propanone oxime in 200 cc of absolute ethanol is treated with 5 grams of Raney nickel catalyst and ammonia in an autoclave at about 25 atm of pressure and at 75 -100°C. The reduction is complete in about one-half hour and the reaction mixture is filtered and fractionated under reduced pressure to recover the a-methylhomoveratrylamine formed by the reduction. a-Methylhomoveratryl-amine thus prepared boiled at 163°-165°C at 18 mm pressure. 

The resulting 4-methylhexanone-2 oxime separates and is dried by any suitable means, such as with a dehydrating agent, for example, sodium sulfate or magnesium sulfate. After drying, 4-methylhexanone-2 oxime is reduced with hydrogen by means of a catalyst, such as Raney nickel, or by reaction of sodium and a primary alcohol, such as ethanol. The resulting 2-amino-4-methylhexane may be purified by distillation, as described in U.S. Patent 2,350,318. 

Heptamide has been prepared by heating heptanoic add with ammonia in a sealed tube 2 at 230°, by treating heptanoic anhydride with ammonia,3 by passing ammonia through heptanoic acid4 at 125-190°, by the rearrangement of heptaldehyde oxime in the presence of Raney nickel in a quartz tube at 150° for 5 minutes,6 by the Will-gerodt reaction with 2-, 3-, or 4-heptanone or heptanal,6-7 and by the action of ammonia on heptanoyl chloride.8... 

A number of organic species, including amides, oximes, and nitriles, undergo reductive amination, a variety of reduction reactions that produce cimines. In general, these processes involve imines, R=N-R, or related species. Reduction processes include hydrogenation using Raney nickel as the catalyst (for nitriles), the reaction with sodium/EtOH (for oximes), and the use of lithium aluminum hydride, LiAlH (for amides or nitriles). Figure 13-16 illustrates the preparation of amphetamine by reductive amination. 

Nitro compounds in presence of carbonyl group are selectively reduced to amines in the presence of Raney nickel catalyst. Hydrazine reduces nitrdes yielding hydrazones. Under controlled reaction conditions other functional groups, including nitroso and oxime, may be reduced. Many partially hydrogenated derivatives, such as azo-, hydrazo-, and azoxy compounds may be obtained by partial reduction with hydrazine. Reaction with chlorobenzene yields benzene. 

Heterogeneous hydrogenation of the C=N bond is a very widely used synthetic process with application to small and large-scale reactions. Many of the catalysts described in other sections may also be employed, for example those based on supported rhodium, palladium etc, and Raney Nickel. This area has been reviewed extensively recently192. Hydrogenation of oximes and hydrazones results in formation of amines. Milder conditions can be used for oxime reduction if the ethylaminocarbonyl derivative is prepared in situ prior to reduction276. 

Raney nickel) of the potassium salt of D-xy/o-5-hexulosonic acid oxime produces a mixture of 5-amino-5-deoxy-L-idonic and -D-glu-conic acid in the ratio of 2 1, which is converted into the methyl ester hydrochloride. Upon treatment with alkali, spontaneous cyclization to the pair of 1,5-lactams occurs. 5-Amino-5-deoxy-L-idono-l,5-lactam and 5-amino-5-deoxy-D-glucono-l,5-lactam were separated by recrystallization. The optical rotatory dispersion curves of both compounds were discussed. A new type of lactam, namely, 2-enamino-N,N -bis[(p-methoxycarbonyl)phenyl]-4-(D-gaiacfo-penta-acetoxypentyl)-4-butanelactam was prepared by tbe reaction of 5,6,7,8,9-penta-0-acetyl-3,4-dideoxy-D-ga/ocfo-nonulos- rcns-3-en-l-onic acid with methyl p-aminobenzoate. 

Hydrogenation with hydrazine and Raney nickel is smooth only for ket-oximes 109 yields are often comparable with those obtained by reduction with lithium tetrahydridoaluminate. The oxime and 64% hydrazine hydrate are dissolved in alcohol, and the reaction is started by addition of a little Raney... 

The nocardicin nucleus 3-aminonocardicinic acid (3-ANA) (7) has not been found in nature, but can be prepared by deacylation of nocardicin C using microbial amidases 10). The first chemical method leading to (7) involved acid treatment of the bisthiourea derivative (8) of nocardicin C 11). A more recent method 12) makes use of the reaction of the oxime grouping of nocardicin A with di-/-butyl dicarbonate. This results in (9) which on treatment with trifluoroacetic acid gives (7). Further confirmation of the structure and stereochemistry of the nocardicins was the identification of the acylamino-derivative (10) derived from 3-ANA, with a compound obtained by partial synthesis from penicillin G 11). Another semi-synthetic approach (75) to the nocardicins from penicillin is by way of the thiazoline (11), the final step being Raney nickel desulphurisation of (12). 

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