S. Ansari et al.
indicated the full reduction of the NO group of nitrofura-
new results with other reported methods for reduction of
4-nitroaniline is made in Table 6. As it is clear, a relatively
good improvement has been achieved in efficiency in terms
of the catalyst amount per mmol of the nitro compound,
reaction time, cost, and temperature. Further studies are
under way to extend the applications of Fe O @SiO @
2
zone. In analogy with the reported mechanisms, [68] it may
be proposed that efficiency of this reduction protocol arises
from intermediation of Ag NPs in electron transfer from
−
BH to NO moiety.
4
2
To further extend the scope of this protocol to non-
aromatic nitro compounds, reduction of nitromethane was
studied, and the results showed that Fe O @SiO @KIT-
3
4
2
KIT-6-Ag NPs, especially to reduction of nitriles in our
laboratory.
3
4
2
6
-Ag nanocatalyst could be utilized as a visual colorimet-
Acknowledgements Partial support of this study by research council
ric sensor for detection of nitromethane in aqueous solu-
tion. Dilute solutions of nitromethane and its reduction
product (methylamine) in water are colorless. Upon reduc-
tion to methylamine, in presence of a few drops of alco-
holic solution of phenolphthaleine, however, a pink color
developes into the solution. When 25 mL of nitromethane
solution was treated with 0.9 mg of Fe O @SiO @KIT-
of university of Guilan is gratefully acknowledged.
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3