Oxidation of Aromatic Amines to Nitro Compounds
General Procedure for the Oxidation
2363
1 mmol of aromatic amine was dissolved in 20 mL of glacial acetic acid
followed by addition of 2 mmol of the tetra-n-alkylammonium bromate and
5 mL of 6 N H2SO4. The solution was refluxed and monitored by TLC. The
reaction was brought to room temperature and poured on crushed ice and
solid filtered. Solid was purified by dissolving in ethanol and poured over
water. The same reaction was also performed by using tetra-n-butylammonium
bromate and similar results were obtained. The products were identified by
[12]
comparing melting points of the products with those found in literature
1
and by comparision of H-NMR spectra. In conclusion, we have devised a
simple method for the preparation of tetra-n-alkylammonium bromates and
used them for the oxidation of aromatic amines to nitro compounds in high
yields.
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Received in India March 8, 2004