2-Substituted Benzothiazoles
1325
placed in a beaker filled with graphite, and then subjected to microwave
irradiation at appropriate power and time (Table III). 2-Substituted
benzothiazoles were obtained in the same way as mentioned in
Method A.
In conclusion the synthesis of a series of 2-substituted benzothiazoles
could be achieved from the reaction of 2-aminothiophenol and aldehydes
on the surface of either silica gel or montmorillonite by using graphite
to provide heat, without using any oxidant. These findings offer further
evidence that the coupling of microwave energy together with the mix-
ture of solid mineral support and graphite will bring a thermal effect
and therefore make the reaction easier.
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