Cyclohexanone oximes 3- methyl

Organoaluminum-promoted Beckmann rearrangement/methylation of cyclohexanone oxime mesylate, followed by allylation of ketimine 40a and Mannich cyclization of the intermediate iminium-allylsilane, provides piperidine 40b possessing cxo-unsaturation (08BKC1669). 

In some very early work the conformation of a-methyl groups in cyclohexanone oximes (76) was assigned from solvent shifts. Results are summarized in Table 17. In solutes bearing a lone pair of electrons on nitrogen, the benzene-solute collision complex is likely to occur at a site as far as possible from the nitrogen. Shifts have been summarized for aziridines, oximes and imines, and for the latter a complex of type 77 was proposed. 

In an aqueous medium, acetylene and ketoximes react in quite a different manner to form pyridines instead of pyrroles (75KGS1427, 75MI3). Thus, acetone oxime gives a symmetric collidine (75KGS1427), whereas cyclohexanone oxime affords 6-methyl-l,2,3,4,7,8,9,10-octa-... 

The reaction was carried out at 200-220°C in a rotating autoclave for 8 hr. Maximum pressure developed in the course of synthesis is 27 atm. Under these conditions, when acetylene instead of CaC2 is used, the yield of pyridines grows to 20-30% (80KGS1299 84MI1). Thus, from cyclohexanone oxime 6-methyl-l,2,3,4,6,8,9,10-octahydrophenanthridine (106) can be prepared. 

Ozonolysis. Ozonolysis of cyclohexanone O-methyl oxime 163 in the presence of 1,4-cyclohexanedione 164 gave a complex reaction mixture containing hydroxylamines 164, as a main product (Scheme 71 <1997T5463>). 

Reaction of cyclohexanone O-methyl oxime 163 with chloroacetone gave a similar spectrum of products with a similar ratio and yield (Scheme 72 <1997LA1381>). 

Ozone was produced with an OREC ozone generator (0.6L/min O2, 60 V), cooled to —78°C, and then bubbled through a solution of 0-methyl-cyclohexanone oxime (10 mmol) and 2-adamantanone (20 mmol) dissolved in 200 ml pentane for approximately 3-6 minutes. Thereafter, the solution was flushed with oxygen for 5 minutes before the mixture was concentrated, the residue purified by flash chromatography using silica gel in petroleum ether/diethyl ether, 98 2, and the product isolated. H- and C-NMR data supplied. 

The photoaddition of an excess of 1-nitrosopiperidine to 3-methylcyclohexene is diastereo-selective and afforded exclusively rran. -2-methyl-6-(l-piperidinyl)cyclohexanone oxime (4) as a mixture of (E)- and (Z)-isomers. The reaction with Ar-nitrosodimethylamine was less efficient and also produced a small amount (2%) of the (E)-trans-regioisomer the major product was separated and reduced to the corresponding 1,2-diamines 5 with slightly different diastereo-selectivity32. The relative ratio of diastereomeric diamines and the relative stereochemistry of the three substituents in the predominant diamine diastereomer were established by HNMR of the. V-acetyl derivative, while those of the minor diastereomer were proposed from mechanistic considerations. The photoaddition of A -nitrosodimethylamine with 4-fer/-butylcyclohex-ene, however, afforded a mixture of diastereomers and regioisomers21,32. 

The reaction of ammoximation is generally apphcable and provides an efficient route to many other oximes in addition to the industrially relevant cyclohexanone oxime. Acetone, butanone, acetophenone, C5—Cg cycUc ketones and methyl-substituted cyclohexanones produced the corresponding oximes with high conversion and selectivity. Even the ammoximation of cyclododecanone and 4-butylcyclohexa-none, unable to diffuse in TS-1, occurred with high yields [121-123]. Other ammo-ximation catalysts are carbon-supported TS-1, TS-2, Ti-MOR and Ti-MWW, with conversions and selectivities close to those of TS-1 [124—128]. 

The reaction is reversible, but the state of equilibrium highly favors the desired products. Preparations of large quantities for synthetic work are illustrated for methyl ethyl ketoxime, cyclohexanone oxime, hept-aldoxime, and benzophenone oxime, the procedures varying somewhat with the nature of the carbonyl compound. In some instances, a readily available and cheap reagent like sodium hydroxylamine disulfonate, HON(SO,Na)j, is first prepared from sodium nitrite and sodium bisulfite and, without isolation, treated with the carbonyl compound, Hydioxylamine-O sulfonic add, Ii,NOSO,H, is still another reagent and, like sodium hydroxylamine disulfonate, is used in the absence of a base. The preparation of hydroxylamine hydrochloride is described. ... 

Secondary amines reacted to form hydrazines in yields of 90% and better. Aniline can be converted to phenylhydrazine. Sometimes the addition was followed by the elimination of water rather than the aminated nucleophile. For example, treatment of 3,3-pentamethyleneoxaziridine with methoxide ion produced cyclohexanone oxime (9-methyl ether. Formanilide reacted with 3-phenyloxaziridine in the presence of sodium ethoxide to produce benzaldehyde phenyUiydrazone. " Of considerable interest is the reaction of Schiff bases with these oxaziridines to produce diaziridines. Other examples are given in Schmitz recent review. One intramolecular version of this kind of amination is known oxaziridine 57 was converted to benzophenone and 5,6-dihydro-4H-l, 2-thiazine 58 upon heating. ... 

Trapping of the Beckmann intermediates with enol silyl ethers affords facile entry to a variety of en-amino ketones. This condensation takes place with retention of regiochemical integrity in both oxime sulfonates and enol silyl ethers. Reaction of 6-methyl-l-(trimethylsiloxy)-l-cyclohexene (41) or 1-methyl-2-(trimethylsiloxy)-l-cyclohexene (42) with cyclohexanone oxime mesylate furnishes (43) or (44), respectively, as the sole isolable products (equation 25). Another striking feature of the reaction is the high chemospecificity. The condensation of the enol silyl ether (45), derived from p-acetoxyaceto-phenone, occurs in a chemospecific fashion with cyclododecanone oxime mesylate, the acetoxy moiety remaining intact (equation 26). Oxime sulfonates of aromatic ketones and cyclopentanones are not employable since complex reaction mixtures are formed. 

Further aminations are the formation of cyclohexanone oxime 0-methyl-ether from 34 and methanol, and of benzaldehyde phenylhydrazone from 3-phenyloxaziridine 41 and formanilide. ... 

Cyclization of oximes with olefins is another route to isoxazolidines. Only a few oximes are reactive, however, and so this method is not very versatile. Reaction of formaldoxime with acrylonitrile104-106 or methyl acrylate104,105 gives 5-substituted isoxazolidines together with N-alkylated species. Benzophenone oxime reacts with but-l-en-3-one to give a similar mixture. 0,107 However, oximes such as acetaldehyde or cyclohexanone oxime do not react with acrylonitrile or acrylic ester,106 although they do react with dimethyl acetylenedicarboxylate to give a 1 2-adduct.108... 

A related reaction employs bis(trimethylsilyl)peroxide in the presence of trimethylsilyl triflate. This procedure works efficiently with various aldehydes and ketones to give good yields of tetroxanes 48 (Equation 26) <2001COR601, 2002RMC113>. Alternatively, dispirotetroxanes can be prepared unambiguously by ozonolysis of cyclohexanone 0-methyl oximes (see Section 9.14.8.2.1) <2001COR601>. 

Ribeiro, D. S., Ohvato, P. R., Rittner, R. (2000), Axial/equatorial populations in a-heterosubstituted cyclohexanone Oximes and O-methyl oximes. Magn. Resort Chem., 38, 627. 

SCHEME 1.151 Formation of 6-methyl-l,2,3,4,7,8,9,10-octahydrophenanthridine from cyclohexanone oxime and acetylene in aqueous KOH. 

The reaction of acetone, cyclopentanone, and cyclohexanone oximes with methyl propynoate (MeOH, 55°C-60°C) affords a mixture of products among which... 

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