Nitrobenzamides

IQ was derived using propylenediamine to the appropriate propylamino derivative and acylated with 4-nitrobenzoyl chloride to nitrobenzamides 105 the ni-trobenzamides were used as haptens to generate the anti-IQ specific monoclonal antibodies (87H2069). 

Nucleophilic attack by carbanion occurs in the reaction of 2-nitrobenzamides 154 treated with sodium ethoxide (72JCS(P1)835). The reaction mixtures usually contain small amounts of nitrile 155 and carboxamide 156, the product of decarboxylation 158 being usually the principal product (Scheme 24). The corresponding bromo derivatives under the used conditions did not react. 

The chemistry of indium metal is the subject of current investigation, especially since the reactions induced by it can be performed in aqueous solution.15 The selective reductions of ethyl 4-nitrobenzoate (entry 1), 2-nitrobenzyl alcohol (entry 2), l-bromo-4-nitrobenzene (entry 3), 4-nitrocinnamyl alcohol (entry 4), 4-nitrobenzonitrile (entry 5), 4-nitrobenzamide (entry 6), 4-nitroanisole (entry 7), and 2-nitrofluorenone (entry 8) with indium metal in the presence of ammonium chloride using aqueous ethanol were performed and the corresponding amines were produced in good yield. These results indicate a useful selectivity in the reduction procedure. For example, ester, nitrile, bromo, amide, benzylic ketone, benzylic alcohol, aromatic ether, and unsaturated bonds remained unaffected during this transformation. Many of the previous methods produce a mixture of compounds. Other metals like zinc, tin, and iron usually require acid-catalysts for the activation process, with resultant problems of waste disposal. 

CN 4-amino-A-[l-(3-cyclohcxen-l-ylmelhyl)-4-piperidmyl]-2-ethoxy-5-nitrobenzamide fumarate (1 1)... 

Aliphatic and aromatic carboxamides, with the exception of p-nitrobenzamide, are dehydrated in this way in high yield. Acid-labile protective groups such as tetra-hydropyranyl and tert-butyldimethylsilyl ether and base-sensitive compounds are not attacked. A,A -Sulfinyldi-1,2,4-triazole, easily prepared from thionylchloride and triazole [THF, (C2H5)3N, 0 °C, 1 h] in 85-95% yield, was used without further purification. 

Fig. 5 Excess acidity plots according to equation (17) for three amides in aqueous perchloric acid at 45°C (upper lines) and 15°C (lower lines). Open circles, 4-methoxy-benzamide closed circles, 3,4,5-trimethoxybenzamide open triangles, 3-nitrobenzamide. Data from ref. 64 numbers to the right of the dashed lines are log/values.

At lower acidities the iV-nitrobenzamides and /V-methyl-.V-nitrobenzamides have a hydrolysis mechanism that is not acid-catalyzed for these cases plots of log kv - log h2o are linear, as for the acyhmidazoles discussed above. N-Nitroacetamide also hydrolyzes in this way.291 The proposed mechanism is given in Scheme 17, written for TV-nitroacetamide if the hydration shown is a pre-equilibrium (this is a carbonyl compound with a strong electron-withdrawing group attached, so this is likely), only one water molecule will appear in the rate expression (the difference between 3 and 2), as observed.287 Some evidence for hydroxide-catalyzed processes at the very lowest acidities was also found for some of these compounds.287... 

A comparison of structures of V-methyl-V-nitroso-p-nitrobenzamide, N,N -dimethyl-V-nitrosourea, V-methyl-V-nitrosourea, 2-nitroso-2-azabicyclo[2.2.2]octan-3-one to those of V-methyl-V -nitro-V-nitrosoguanidine and V,V -dimethyl-V"-cyano-V-nitrosoguanidine shows that the N—N and C—NNO bond lengths in the nitroguanidines44 are similar to those found in the nitrosoamides, but that the corresponding bonds in... 

Ar-[2-(dimethylamino)ethyl]-3-r-butyl-2-nitrobenzamide hydrochloride nitro quinolines H /CH3 92... 

Olsen and co-workers used a solution of nitronium tetrafluoroborate in acetonitrile for the V-nitration of acetamides and urethanes at —30°C. The following nitramides were obtained by this method V-nitroacetamide (13 %), V-nitro-2-chloroacetamide (55 %), V-nitro-n-butylacetamide (40 %), V-nitrobenzamide (53 %), ethyl V-nitro-n-butylcarbamate (91 %) and V-nitrosuccinimide (43 %). The low yield of V-nitroacetamide, a primary nitramide, is attributed to competing hydrolysis due to the release of tetrafluoroboric acid as the reaction progresses. The scope of the reaction is improved by moving to more basic solvents like ethyl acetate, 1,4-dioxane and trimethyl phosphate. ... 

Amides containing nitro groups are reduced to diamino compounds with alane. A, A -Dimethyl-p-nitrobenzamide, on reduction with lithium aluminum hydride in the presence of sulfuric acid in tetrahydrofuran, gave 98% yield of dimethyl-p-aminobenzylamine [1117]. 

Ci4Hi2iN204 iV-Hydroxy-A-(3-methyl- phenyl)-2-nitrobenzamide Gravimetric Ce, Gd, La, Nd, Pr, Sm 3... 

C14H12N2O4 A -Hydroxy-A-(4-methyl- phenyl)-3-nitrobenzamide Extiaction-photometric V 3... 

Diafkoxyamines, though less nucleophilic than their dialkylamine counterparts, react with acyl chlorides to yield A, A-dialkoxyamides directly . For example, with 4-nitrobenzoyl chloride (189), dimethoxyamine (188) was converted to A,A-dimethoxy-4-nitrobenzamide (190) in 55% yield (equation 24). 

Mendeleyev J, Kirsten E, Hakam A et al (1995) Potential chemotherapeutic activity of 4-iodo-3-nitrobenzamide metabolic reduction to the 3-nitroso derivative and induction of cell death in tumor cells in culture. Biochem Pharmacol 50 705-714... 

When 1,2-dihydroquinazolines are actually desired as the reaction product, they can often be contaminated with their conjugated analogs due to spontaneous dehydrogenation <2000JME4479>, but this can be avoided under reductive conditions, as demonstrated by the preparation of 2-substituted-l,2-dihydroquinazolines 815 by the reductive condensation of 2-nitrobenzamides 814 with aldehydes in the presence of samarium iodide <2002JHC1271>. 

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