EXPEDITIOUS SYNTHESIS OF AROMATIC CYANODIENONES USING NEUTRAL ALUMINA AS A VERSATILE HETEROGENEOUS CATALYST

The work described herein employs neutral alumina as an effective catalyst for ring opening of triarylpyrylium perchlorates to corresponding aromatic cyanodienones, which have main roles in biological activities. The present porous catalyst has several advantages, it is inexpensive, thermally and mechanically stable, nontoxic, and highly resistant against organic solvents. It increases the reaction rate many fold when compared with conventional reaction conditions. Moreover, the recovered alumina can be used several times without serious decrease in activity. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) for the following free supplemental resource(s): Full experimental and spectral details.]