Abstract
A highly efficient and simple procedure for the synthesis of substituted benzenes is described. A broad range of ketones (alkyl–aryl ketones and cyclic ketones) were condensed via a cyclotrimerization reaction in the presence of catalytic amounts of boron sulfonic acid [B(HSO4)3], a new, highly efficient, and reusable catalyst, under solvent-free conditions. All reactions completed in short times without formation of any by-products. The catalyst was recovered and reused successfully for 15 cycles of the reaction.
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GRAPHICAL ABSTRACT
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ACKNOWLEDGMENT
We thank the Islamic Azad University (Shiraz Branch) Research Council for the financial support of this work.
Notes
a Isolated yield.
b For more informations see Ref. 38.
c For more informations see Ref. 39.
d For more informations see Ref. 40.
a Isolated yield.
a Isolated yield.
a Isolated yield.