Multicomponent 1,3-Dipolar Cycloaddition Reactions in the Construction of Hybrid Spiroheterocycles

Spiroheterocyclic ring systems are attractive synthetic targets due to their interesting conformational features and their structural implications on their activity in biological systems. Consequently, a vast deal of research by synthetic organic as well as medicinal chemists pertains to the synthesis of these heterocycles employing diverse synthetic methodologies. Among them, one-pot multicomponent 1,3-cycloaddition reactions have emerged as preferred synthetic protocol in view of their convergence, atom economy, ecofriendliness, flexibility and facile automation. This review article focuses on the assembly of mono-, di- and multispiro heterocyclic hybrids via aforesaid synthetic methodologies with a variety of dipolarophiles.