Oxime reactions

Reactions with Amines and Amides. Hydroxybenzaldehydes undergo the normal reactions with aUphatic and aromatic primary amines to form imines and Schiff bases reaction with hydroxylamine gives an oxime, reaction with hydrazines gives hydrazones, and reactions with semicarbazide give semicarbazones. The reaction of 4-hydroxybenzaldehyde with hydroxylamine hydrochloride is a convenient method for the preparation of 4-cyanophenol (52,53). 

Dihydrocinchonicine, 452 Dihydrocinchonidine, 429 Dihydrocinchonine, 428 Dihydrocinchotoxine, 452 Dihydrocodeine, 260 Dihydrocodeinone, 245, 260, 270 Dihydroeodeinone oxime, reactions, 244 Dihydromeiacodeinone, 249 Dihydrocryptopine and isodihydrocryptopine, 296 Dihydrocupreicine, 452 Dihydrocupreidine, 431 Dihydrocupreine, 431 Dihydrodeoxymorphines, 254, 260-2 Dihydroecgonidine, 99 Dihydro- -erythroidines, 387... 

The scheme required to prepare the potent tri-fluoro corticoid cormethasone acetate (292) illustrates the synthetic complexities involved in some of this work. Sequential acetylation of the pregnenolone derivative 278 with first acetic anhydride in pyridine and then acetic anhydride in the presence of tosic acid affords diacetate 279. Reaction of that intermediate with nitrosyl fluoride results initially in addition of the reagent to the 5,6-olefin moiety to afford the fluoro oxime reaction with a second mole of reagent at nitrogen gives the nitroimine derivative 280 passage over alumina serves to hydrolyze the imine function to the corresponding 6-ketone (281). 

Preparation of 2-dimethoxyphosphinyl-2-methoxy-2-phenylacetaldehyde oxime — Reaction of an unsaturated nitro compound with a trialkyl phosphite in the presence of an alcohol... 

Difluoroaspartic acid has been prepared by electrophilic fluorination of Ai-tert-butyl 2-ketosuccinate. The amino group is further introduced via an oximation reaction, followed by a reduction. Difluoroaspartic acid may be converted further into difluoroasparagine (Figure 5.19). 

It is prepared by treating p-chloromethylaniline with benzoyl chloride and hydroxylamine to produce the benzophenone oxime. Reaction of the oxime with chloroacetyl chloride in the presence of sodium hydroxide, and subsequent reduction, yields diazepam. 

Acetone oxime, reaction with ethyl m-bromopropionalc, 48, U1... 

Figure 7 Application of the Barton oximation reaction to carborane chemistry...

Pentose sugars may be obtained by the oxidation of the normal penta-hydroxy alcohol. The usual method of preparing them, however, is by decreasing the carbon content of a hexose sugar by means of the oxime reaction (p. 330). 

Sedergran,T. C. Anderson, C. F., Copper-mediated oximation reaction U.S. 4,675,398,1987 (to E. R. Squibb Sons) Cimarusti, C. M., contributed talk at The Third International Conference on Process Development, Amelia Island, FA, March 26,1997. 

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