1- acetophenone oxime

S612). However, more work is needed to determine its full utility. Table 16 lists the types of isoxazoles synthesized from the condensation of 1,4-dilithio oximes (358) and 2-nitro-acetophenone oximes with electrophiles. 

The present procedure was developed from those of Wallach and Freylon, based upon the general method discovered by Leuckart. a-Phenylethylamine also can be prepared satisfactorily by the reduction of acetophenone oxime with sodium and absolute alcohol or sodium amalgam, but the reagents are more expensive and the processes less convenient. The amine has been obtained by reducing acetophenone oxime electro-lytically, by reducing acetophenone phenylhydrazone with sodium amalgam and acetic acid, from a-phenylethyl bromide and hexamethylenetetramine, and by the action of methyl-magnesium iodide upon hydrobenzamide, as well as by other methods of no preparative value. 

Natrium-trifluoracetoxy-trihydrido-borat reduziert O-Alkyl-oxime in siedendera Tetrahydrofuran zu prim. Aminen. So erhalt man z. B. aus O-Methyl-acetophenon-oxim 1 -Phenyl-dthylamin zu 90% d.Th.. ... 

O-Acylated or mesylated oximes such as the ethyl carbonate of acetophenone-oxime 1772 react with TIS 17, with Beckmann rearrangement to the imidoyl iodide 1773, which adds phenylmagnesium bromide in situ to give 61% of the sec-... 

Sodium perborate in acetic acid converts oximes into nitro compounds thus acetophenone oxime yields 52% of PhCHMeN02403. Nitroalkanes and nitroarenes are obtained from isocyanates and dimethyldioxirane (equation 122)404. 

Treatment of the nitronate salt 397 (from nitroethane and methanolic sodium methoxide) with benzene in the presence of trifluoromethanesulphonic acid gives acetophenone oxime, which is obtained mainly as the (E)-isomer 398433. 

Kinetic studies of the oxidation of some a-hydroxy acids with pyridinium dichromate (PDC) are consistent with a mechanism involving the loss of H2O from the pro-tonated substrate in the rate-determining step. The oxidation of 8-hydroxyquinoline (oxine) by PDC has been studied. The intermediacy of an acetochromate ion in the oxidation of some acetophenone oximes with PDC is suggested. 

Preparative scale reduction of oximes at a mercury or lead cathode in acid solution has been used in the conversion of the carbonyl function to amine. Originally, 30-50% sulphuric acid was used as solvent [195] but ethanol with dilute hydrochloric acid is usually satisfactory. Aliphatic and aromatic oximes give amines in 64-86% yields [196]. Aromatic ketoximes are also reducible in alkaline solution and acetophenone oxime has been converted to 1-phenylethylamine in a tri-potassium orthophosphate solution [197], The reduction of oximes in acid solution is tolerant of many other substituents as indicated by a number of examples [198, 199, 200. Phenylglyoxa monoxime in acid solution is however reduced at both the carbonyl and the oxime centres by sodium amalgam to yield 2-amino-1-phenylethanol [201]... 

A possible synthesis of the extensively studied 4,5-dichloro-l,2,3-dithiazolium chloride (Appel salt) analogs (see next section) was found in the reaction of acetophenone oxime and its 4-nitro derivative with S2CI2 (1994H1827, 1997BSB605 Scheme 73). 

Pyrrolopentathiepin 231 was found as a minor by-product in a curious and completely unexpected reaction of acetophenone oxime and sulfur monochloride in the presence of pyridine and o-aminophenol (1997BSB605 Scheme 123). A possible mechanism was suggested. 

We will look at three pairs of syn and anti aldoxime isomers, 9A and 9B, corresponding to R = CH3 (acetaldoxime), R = CH2CI (chloroacetaldoxime) and R = CgH5 (benzal-doxime). We will also consider the two isomeric forms lOA and lOB of acetophenone oxime, a ketoxime in which R = CH3 and R" = CeHs. 

The preparation of oximes from olefins is a valuable approach for the synthesis of nitrogen-containing compounds such as amino acids and heterocycles. Okamoto and colleagues have reported that a catalytic reduction-nitrosation of styrenes 31 with ethyl nitrite and tetrahydroborate anion by the use of bis(dimethylglyoximato)cobalt(II) complex afford the corresponding acetophenone oximes 32 (Scheme 23). 

Sugamoto and colleagnes have attempted the rednction-nitrosation of the conjn-gated olefins 33 by the nse of f-bntyl nitrite instead of oxygen (Scheme 24). Various olefins such as styrenes, a,-unsaturated carbonyl compounds and a, S,y,5-unsaturated carbonyl compounds were directly converted to the corresponding acetophenone oximes, a-hydroxyimino carbonyl compounds and y-hydroxyimino-a,/S-unsaturated carbonyl compounds in good or moderate yields by rednction-nitrosation with f-butyl nitrite and triethylsilane in the presence of cobalt(II) porphyrin as a catalyst (Scheme 24). 

C8H7CI2NO2 3 5 -Dichloro-2 -hydroxy-acetophenone oxime Complexing agent Extraction-photomehic Gravimetric Photomehic Be, Cd, Co, Mn, Ni, U, V, Zn Co, V Pd Mn, U 3... 

Q0H13NO3 2-Hydroxy-4-ethoxy-acetophenone oxime Gravimetric Zr 34... 

C10H13NO3 2,4-Dihydroxy-5-ethyl-acetophenone oxime Gravimetric Te 35... 

C H,5N03 2-Hydroxy-4-isopropoxy-acetophenone oxime Gravimetric Spectrophotometric Mn Mn 46... 

Hi7JNU3 2-Hydroxy-4-jz-butoxy-acetophenone oxime Gravimetric Extiaction- spectiophotometiic Cu Cu 49, 50... 

FIGURE 8. Hammett plots for reactions of 4-nitrophenyl benzoate (PNPB) with Z-substituted acetophenone oximates ( ) and phenoxides (O) in 20 mol% DMSO (A) and 90 mol% DMSO (B) at 25.0 0.1 °C. Reprinted from Tetrahedron Lett., 36, Um, Oh and Kwon, 6903, Copyright (1995), with permission from Elsevier... 

Sheradsky has found that the hydroxyl function of a ketoxime such as acetophenone oxime can be made to react with DMAD when the reaction is carried out in methanol with a basic catalyst, to give mixture of the fumarate and maleate isomers (164) in the ratio 2 1. This mixture on heating undergoes a hetero-Cope rearrangement followed by cyclization and dehydration to give dimethyl 5-phenylpyrrole-2,3-dicarboxylate (168) (Scheme 25). Similarly, Heindel and Chun have reported that vinyl ether adducts (171), obtained by the condensation of arylamide oximes with DMAD, get thermally converted into oxa-diazolines (172) or imidazolinones (174), depending on the reaction conditions. A similar reaction occurs with aromatic amidoxime-methyl propiolate adducts to give imidazoles (170) (Scheme 26). 1,2,4-Dioxazoles have been reported to be formed in the reaction of hydrox-amic acids with DMAD. - ... 

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