New route to 1,4-oxazepane and 1,4-diazepane derivatives: synthesis from N-propargylamines

N-Propargylamines are one of the most useful and versatile building blocks in organic synthesis that are successfully transformed into many significant N-heterocycles. Due to high atom economy and shorter synthetic routes, the synthesis of 1,4-oxazepane and 1,4-diazepane cores from N-propargylamines have undergone an explosive growth in recent years. This review gives an overview of new developments in the synthesis of the title compounds from N-propargylamines in recent years. Mechanistic aspects of the reactions are considered and discussed in detail.