Synthesis of heterocyclic compounds based on ketene aminal: A systematic review

Heterocyclic compounds play a very important role in both life and drug discovery, and in particular, a large number of synthetic molecules based on these structures have been reported with great potential in medicinal chemistry. Small polycyclic heterocycles are often found in pharmacophores and play an important role in drug discovery. Ketene aminals are multifunctional building blocks for the synthesis of all kinds of compounds. Bicyclic, tricyclic, and tetracyclic nitrogen-containing analogs with ketene aminal skeletons are widely available in natural and synthetic drugs. In recent years, significant progress has been made in the chemistry of ketene aminals. To understand and dominance the reaction properties of ketene aminals and the synthesis of other novel fused heterocycles, the investigation of ketene aminals is very important and necessary. This review covers relevant contributions with regard to the development and applications of ketene aminals, classified by reaction type and type of synthetic products.