2
6
M. Ghiaci et al. / Applied Catalysis A: General 384 (2010) 18–26
Fig. 4. Formation of p-bromotoluene versus time for experiments 1–6.
CO32 –Br to the reaction mixture resulted in more than 4-fold
−
−
resulted in more than 2–4-fold increase in the rate of bromination
of anisole and toluene, respectively.
increase in the rate.
Acknowledgment
3.2.4. Effect of the reactant and the phase-transfer catalyzed
system concentration on the rate of bromination of toluene
Thanks are due to the Research Council of Isfahan University of
Technology and Center of Excellence in the Chemistry Department
of Isfahan University of Technology for supporting of this work.
In this case also we have changed systematically the amount
of V O5, H O and LDH-CO32 –Br in order to determine the rate
−
−
2
2
2
dependence on each species. Table 6 contains a summary of the
results of these experiments. The rates were determined from the
graphs of p-bromotoluene product formed versus time (Fig. 4). A
comparison of the rates of p-bromotoluene formation for experi-
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