Cyclization and Rearrangement Approaches

Cyclization and rearrangement reactions such as the Dimroth rearrangement have played an important role in the synthesis of quinazoline-containing compounds. For example, Reddy and co-workers applied the Dimroth 

Fabis and co-workers used a base-catalyzed ring contraction to generate 2-pyrryl substituted quinazolinones. Treatment of pyrrolo[2,l-c][l,4]benzodiazepine with hydrazine in ethanol at room temperature provided the desired quinazolinone in 60% yield. 

Ganesan and Wang used a base-catalyzed condensation between a tricyclic lactam and a sulfinyl benzoyl chloride derivative in the final step of their total synthesis of the cytotoxic alkaloid luotonin The desired product was produced in 85% yield after condensing at room temperature under basic conditions for 13 h. 

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