Thermal [3+2] cycloaddition reactions as most universal way for the effective preparation of five-membered nitrogen containing heterocycles

The possibility of the construction of five-membered heterocycles, including single heteroatom or systems with two, three and four heteroatoms were critically reviewed based on the recent reports regarding to the [3+2] cycloaddition reactions. Almost all of analysed reaction are realized with high regio- and stereoselectivity.