This review summarizes the most recent progress made in C–H bond activation-initiated spiroannulation reactions and their applications in the construction of structurally diverse and biologically valuable spirocyclic scaffolds.
The present review summarizes the recent advances (2018–2023) in stereoselective annulation involving p-benzoquinones for the construction of fused, spiro and bridged/cage frameworks.
The advancements in the synthesis of nitrogen-containing heterocycles via Rh(III)-catalyzed chelation-assisted tandem C–H activation/carbene insertion/annulation with diazo compounds as carbene precursors have been summarized.
An unusual Au(I)/Sc(III)-co-catalyzed tandem spiroannulation/cycloisomerization of 3-(2-ethynylaryl)-N-tosylaziridine-2,2-diesters with indoles has been reported. A variety of 5H-benzo[b]carbazoles were obtained in moderate to good yields (30–88%).
A Co(III)-catalyzed C–H functionalization/spiroannulation of 1,3-indandione with alkenes has been developed for the synthesis of spiroindenes. This efficient protocol features excellent functional group tolerance and high atom- and step-economy.