In this article we describe a strategically unusual approach to piperidines via formal [3 + 3] cycloaddition reactions. The scope and limitations of these processes are outlined and their employment in the synthesis of alkaloid natural products is delineated.

Quinazolinones are an important class of heteroaromatic compound, and they are prevalent in a variety of important bio-active scaffolds. Traditionally, their synthesis has been achieved via classical condensation procedures, however over recent years catalytic methodologies have emerged as effective alternatives. This review examines recent developments in the employment of catalytic approaches towards this highly important heterocyclic motif.