Hydrazones as substrates for cycloaddition reactions

The $[2+2]$-, $[4+2]$- and $[3+2]$-cycloaddition reactions of hydrazones and $1,2$-diazabuta-$1,3$-dienes, azomethine imines, nitrile imines and azomethine ylides formed upon hydrazone transformations with dienophiles, dipolarophiles and dienes are considered. The principal issues of structure and reactivity of active substrates and the influence of the reaction conditions and catalysts on the reaction regioselectivity and efficiency are discussed.
The bibliography includes 288 references.