Acetophenone 3-nitro

Nitro-aldehydes—Nitro-ketones—Nitro-acetophenone—Nitro-... 

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. 

A solution of N-(2-aminobenzvl)-1-phenyl-2-metKylaminoethanol-1 was prepared by the reaction of a-bromo-acetophenone and (2-nitrobenzyl)methylamine, followed by hydrogenation of the nitro group by means of nickei on diatomaceous earth at room temperature and reduction of the CO group by means of sodium borohydride. The intermediate thus produced was dissolved in 100 ml of methylene chloride and introduced dropwise into 125 ml of sulfuric acid at 10° to 15°C. After a short standing, the reaction mixture was poured onto ice and rendered alkaline by means of a sodium hydroxide solution. Dy extraction with ether, there was obtained 1,2,3,4-tetrahydro-2-methyl-4-phenyl-8-amino-iso-quinoline. The base is reacted with maleic acid to give the maleate melting point of the maleate 199° to 201°C (from ethanol). 

Je nach Bedingungen kann auch Hexaathyl-disiloxan entstehen. Die bei 20° ablaufende Reaktion ist stark strukturabhangig. Elektronenliefernde Substituenten fordern, elektro-nenanziehende erschweren die Reduktion. So wird 4-Nitro-benzophenon z.B. erst inner-halb 47 Stdn. zu 4-Nitro-diphenylmethan reduziert, wahrend 4-Nitro-benzaldehyd und -acetophenon nicht bis zu Kohlenwasserstoffen reduziert werden. 

Auch Kalium-tetracarbonyl-hydrido-ferrat(O) reduziert in Athanol 2-Nitro-acetophe-non selektiv zu 2-Amino-acetophenon 2-Nitro-zimtaldehyd wird in quantitativer Aus-beute reduktiv zu Chinolin cyclisiert6 ... 

These authors observed that in 80% aqueous ethanol, the rates were pseudo first order in bromostyrene, except for the P-NO2-isomer, which did not react even at 190° C. The products of reaction in the cases where X = NH2, CH3CONH, and CH3O were exclusively the corresponding acetophenones and, for X = H, 74% acetophenone and 22% phenylacetylene. Reaction rates were found to increase with solvent polarity as well as addition of silver ion, but they were independent of added triethylamine (except in the very unreactive p-nitro isomers, where in the presence of added amine, a second-order reaction ensued that resulted exclusively in p-nitrophenylacetylene as product). 

The Michael reaction of benzylidene acetophenone and benzylidene acetone with ethyl acetoacetate, nitromethane, and acetylacetone was studied by Musaliar and co-workers in the presence of a cetyltrimethy-lammonium bromide-containing aqueous micellar medium.50 The Michael reaction of various nitro alkanes with electrophilic alkenes is performed in NaOH (0.025-0.1 M) in the presence of cetyltrimethylam-monium chloride (CTACI) without any organic solvent (Eq. 10.23).51... 

These reaction conditions also permit the chemoselective quantitative reduction of benzaldehyde to benzyl alcohol without any concomitant reduction of either acetophenone or 3,3-dimethylbutan-2-one present in the same reaction mixture.83 Additionally, this useful method permits the reduction of aldehyde functions in polyfunctional compounds without affecting amide, anhydride, eth-ylenic, bromo, chloro, or nitro groups.79,80,319... 

Asymmetric reduction of 2-bromo-(3-nitro-4-benzyloxy) acetophenone. . 157... 

ASYMMETRIC REDUCTION OF 2-BROMO-(3-NITRO-4-BENZYLOXY)ACETOPHENONE[161... 

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. 

The aryl rings of acetophenone and methyl benzoate are preferentially hydrogenated, with only minor reduction of the substituents. In contrast, hydrogenation of nitrobenzene, under essentially the same conditions, produces aniline and nitro-cyclohexane in ca. 9 1 ratio, with an overall conversion of >79%. This observation has additional significance when compared with the hydrogenation of the nitro derivative of vinylbenzene (Table 11.25). In all cases, it is the C=C bond which is hydrogenated and, only after a prolonged reduction time, is 1-nitro-2-phenylethene completely reduced to the aminoethane [4],... 

The anion-radicals from aromatic nitro compounds preserve the second-order axis of symmetry. The analysis of superfine structure of the ESR spectrum of the nitrobenzene anion-radical reveals equivalency of the ortho and meta protons (Ludwig et al. 1964, Levy and Myers 1965). With the anion-radical of nitrosobenzene, the situation is quite different. This was evidenced from the ESR data (Levy and Myers 1965, Geels et al. 1965). Following electron transfer, the bent nitroso group fixes in the plane of the benzene ring to a certain extent. This produces five different types of protons, since both meta and ortho protons become nonequivalent. The nonequivalence of the ortho and meta protons has also been established for the anion-radicals of acetophenone (Dehl and Fraenkel 1963) and 5-methylthiobenzoate (Debacher et al. 1982 Scheme 6.17). 

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). 

Erhitzt man 3-Azido-2-nitro-acetophenon, erhalt man nach Stickstoff-Abspaltung nicht das 4-Acetyl-benzofurazan-l-oxid (X), sondern 3-Methyl-7-nitro-2,l-benzoxazol (s. S. 788)272. 

Die Umsetzung von Styrol mit einem Natriumnitrit-Salzsaure-Gemisch bei 0° in Wasser/ Benzol fuhrt zu 2-Nitro-l-nitroso-l-phenyl-ethcm (90-94%). Erhitzen in waBr. Salzsaure auf 75° liefert co-Nitro-acetophenon (90-92%) und Erhitzen in Ethanol/Triethylamin auf 60° liefert (o-Nitro-styrol (95%)3 ... 

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