Zeolite H-Y–Supported Copper(II) Nitrate
1751
brown gas evolved. The progress of the reaction was monitored using TLC
4:6 ethyl acetate/hexane). The product mixture was extracted with chloro-
(
form and separated by column chromatography and analyzed using spectral
methods. A similar method was adopted for the preparation of reaction
mixture, and the mixture was irradiated using a microwave oven at 900 W
for different time intervals. All of the isolated products are known
compounds, and their spectra and physical data have been reported in the lit-
[
1,10–15]
erature.
CONCLUSION
Phenols are selectively nitrated to para-nitro derivatives in high yields with
copper nitrate–zeolite catalyst. The catalyst could be easily separated from
the reaction mixture for recycling, and the workup procedure for isolation
of reaction products is simpler as compared to the conventional process.
The regioselective nitration of phenol using cupric nitrate over solid acid,
catalyst without any use of acetic anhydride/acyl nitrate, nitric acid, or
sulfuric acid is a comparatively clean and environmentally friendly process.
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9