Cycloheptanone oxime

The lactam (2) is obtained in 87% yield by treating cycloheptanone with sodium azide and concentrated hydrochloric acid (54JA2317). Beckmann rearrangement of cycloheptanone oxime with concentrated sulfuric acid gives (2) in 88% yield (58JA1510). Alternatively, the ketone gives (2) directly by reaction with hydroxylamine sulfonate in 95% formic acid (79S537). 

The benzenesulfonate of cycloheptanone oxime rearranges readily at room temperature to give the very electrophilic O- benzenesulfonate (7), which reacts with pyridine to give the salt (8) (67CB3024). Treatment of (8) with water gives (2), and with H2S the thione (9) is produced (58CB972). The reaction of aluminum alkyls with cycloheptanone oxime mesylate provides a direct route to 2-alkyl-substituted octahydroazocines (81JA7368). 

Methylcyclohexanone and suberone (cycloheptanone) oximes correspondingly give 7-methyl-4,5,6,7-tetrahydroindole (33, yield 70%), its N-vinyl derivative [34, yield 80% (75MI1)], and 4,5,6,7,8-pentahydro-l//-cyclohepta[6]-pyrrole [35, yield 79% (76MIP1 80KGS1299)] (Table XIX). 

Hexahydroazocines. The synthesis of stable ketene aminal diphenylphosphates 46 was accomplished departing from the eight-membered iV-BOC or iV-COOPh protected lactams 45 via their potassium enolates (Scheme 13 <1998CC1757>). Azocane-2-one 45 was easily obtained from cycloheptanone 44 by Beckmann rearrangement of its cycloheptanone-oxime and subsequent protection of the amino moiety. 

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... 

Die Hydrierung des destillierten Cycloheptanon-oxims in einer Parr-Apparatur bei 3 bar fiihrt etwa zu der gleichen Gesamtausbeute. 

The synthesis of aza-2-cycloheptanone (e-caprolactam) by the Beckmann rearrangement of the oxime of cyclohexanone is of commercial importance because the lactam is an intermediate in the synthesis of a type of nylon (a polyamide called nylon-6 2) ... 

Nylon 6 can be prepared by polymerization of l-aza-2-cycloheptanone (e-caprolactam), obtained through the Beckmann rearrangement of cyclohexanone oxime (Section 24-3C) ... 

Kinetics and activation parameters for the oxidation of phenol with tetrakis(pyridine) cobalt(II) chromate have been determined.16 The oxidation of oximes of cyclopen-tanone, cyclohexanone, and cycloheptanone with pyridinium fluorochromate is first order each in the oxidant and oxime. The observed reactivity sequence has been rationalized on the basis of I-strain.17... 

The procedure described is a one-step conversion of cycloheptanone into hexahydro-2(lH)-azocinone. The method is general and is characterized by good yields, mild conditions, and easy preparation of the product in pure form from readily available starting materials. Several methods are described in the patent literature for simultaneous oximation of ketones and rearrangement to the corresponding oxime, Including the use of hydroxylamine and sulfuric... 

From cyclohexanone via suberone (cycloheptanone) by oximation to yield enantholactam, but the diazotization occurs with a poor yield ... 

A soln. of 4 kg. cycloheptanone in methanol treated with hydroxylamine hydrochloride, stirred 1 hr. at 80°, then aq. NaOH added during 4 hrs. at the same temp., refluxed 1-2 hrs., the resulting crude oxime (Y 86%) dried, dissolved in methanol, and hydrogenated with 5%-rhodium-on-alumina at 0.75-1 atm. whereby the temp, rises gradually to 60° and is maintained there until reduction is complete -> cycloheptylamine. Overall Y 80%. M. Freifelder, W. D. Smart, and G. R. Stone, J. Org. Ghem. 27, 2209 (1962). 

From cycloheptanone [201], cyclooctanone [202], and cyclododecanone [202] oximes, the corresponding pyrroles and their N-vinyl derivatives are synthesized (90°C-140°C) in high yields (up to quantitative ones. Scheme 1.31). 

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