Aminobenz aldehyde

Isothiazolium salts (59) react with phenylhydrazine to give pyrazoles (60) (72AHC(14)l) (see Section 4.02.1.6). When treated with hydrazine hydrate, 3-chloro-l,2-benzisothiazole gives di-(o-cyanophenyl) disulfide (73SST(2)556), but 2,1-benzisothiazole gives o-aminobenz-aldehyde azine (72AHC( 14)43). 2-Substituted saccharins give the expected o-sulfamoyl-benzohydrazides. 

Pentagastrin Silica gel G Analyte is examined by TLC in three different mobile phases 4-dimethyl -aminobenz -aldehyde in methanol/HCI The Rf of the analyte in three different mobile phases is determined and the colour of its spot is matched to that of the standard... 

In this case, the 2-aminobenzyl alcohol is oxidized to 2-aminobenz-aldehyde, which undergoes an aldol condensation with the ketone to give an 0, /3-unsaturated ketone. This is followed by cyclodehydratisation to form quinoline. An excess of ketone is necessary to act as a sacrificial hydrogen acceptor. 

A reaction which formally resembles a Friedlander synthesis is that between o-aminobenz-aldehyde and iodobenzene, the resulting 2-formyldiphenylamine being cyclized by acid to give acridine (17CB1306). Quinolines (372) can be synthesized by passing mixtures of o-nitrobenzaldehyde and alcohols over a Cu-Ni-V205 catalyst at 300-320 °C (76MI20801). 

Thin-layer chromatography has also been employed in the analysis of these compounds (9,38,150,155-159). Several developers, such as silver nitrate (150,158), / -dimethyl-aminobenz-aldehyde (38), or UV light (150,158) have been used. Derivatization techniques, based on the urea hydrolysis to the corresponding aniline and ulterior reaction with dansyl chloride, have also been carried out (9,159). Moreover, TLC is frequently employed in studies of metabolization with radiolabeled compounds (155-157). 

Nothing is known about analogous condensation reactions of o-alkyl-aminobenzaldehydes with a,/3-unsaturated cyclopentenones leading to pseudoazulenes 39, 43, or 46. Acid-catalyzed reaction of o-aminobenz-aldehyde with cyclopentenones produces 3//-cyclopenta[b] quinolines that can be transformed to 4H-cyclopenta[b]quinolines by quaternization and subsequent deprotonation.51... 

AMINOBENZ ALDEHYDE, 31,6 -Aminobenzaldehyde hydrazone, 31, 7 -Aminobenzaldehyde oxime, 31, 7 -Aminobenzaldehyde phenylhydra-zone, 31, 7... 

The condensation of a heterocyclic enamine with o-aminobenz-aldehyde, leading to the alkaloids of Peganum harmala, desoxy-vasicine371 and vasicine,372 also include aldol-type reactions. The... 

Isatin has been reported to yield 3-nitrocinchoninic acid (92 R = C02H) with nitromethane in aqueous KOH.83 Although this seems like the use of a type 1 synthon, it is more appropriate to regard it as another example of a methazonic acid reaction. The reaction of nitroacetone with o-aminobenz-aldehyde leads to 2-methyl-3-nitroquinoline derivatives.84... 

Amino-5-deoxy-D-xylopyranose (34 = 17) is like 2-piperidinol (2-hydroxypiperidine) in existing in a pH-dependent equilibrium with its dehydration product (33 = 16). The ultraviolet peak of the n-7T transition of the C=N chromophore of 33 is not suitable for structural elucidation. However, the asymmetric nature of this chromophore gives rise to a Cotton effect. A solution of free 5-amino-5-deoxy-D-xylose shows a negative Cotton effect at 300 nm that is well demonstrable by measurement of circular dichroism for this purpose, the optical rotatory dispersion is much less sensitive. The Cotton effect is ascribable to 33, as 34 and 22 would exhibit no Cotton effect in this region. Thin-layer chromatograms of 34 always show a second spot which, like 34, gives a red coloration with o-aminobenz-aldehyde this is, presumably, caused by 33. 

The second example is noteworthy because condensation of -aminobenz-aldehyde with the same carbonyl component under Friedlander conditions results in... 

To a stirred heterogeneous mixture of neutral alumina (1 g) and 2-aminobenz-aldehyde (1 mmol) was added 1 mmol of the appropriate nitroalkane and the obtained mixture was warmed at 50 °C under stirring for 1.5 h. Then, the mixture was cooled at room temperature and directly charged onto a chromatography column to give the pure product. 

Benzotriazines are ring-opened by aqueous acid at room temperature yielding o-aminobenz-aldehydes, whereas 4-substituted derivatives require heating to form <9-aminoaryl ketones. 1,2,3-Benzotriazin-4(37/)-ones 1 suffer acid cleavage of the heterocycle producing the diazonium ion 2 derived from anthranilic acid amide. Subsequent reactions of these ions involving the A-amino system 3 lead to the anthranilic acid azide 4 by an internal redox disproportionation ... 

Photo-induced cyclization using a norbornene-substituted aminobenz-aldehyde resulted in a minor endoperoxide side product 200, where a 1,6-diradical formed in the reaction can rearrange and be trapped with oxygen to yield the endoperoxide which was characterized by X-ray crystallography (14PCA10487). 

The synthesis of dZ-vasicine under conditions which might occur in plant cells has been achieved by the condensation of o-aminobenz-aldehyde with a-hydroxy-y-aminobutyraldehyde followed by catalytic reduction 248). 

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