A sequential [3 + 2]/[2 + 1] annulation domino reaction of crotonate-derived sulfur ylides and Morita–Baylis–Hillman carbonates of isatins for the construction of oxospiro­[bicyclo[3.1.0]­hexane-6,3′-indolin] scaffolds in moderate to good yields with almost 1:1 diastereoselectivity has been developed. Mild reaction conditions and readily accessible starting materials as well as excellent functional group compatibility render this transformation a powerful tool for the synthesis of spirocyclopropyloxindoles. A gram-scale synthetic procedure was also successfully carried out and a plausible reaction mechanism could be proposed.

A protocol for the reaction of ketone or ester enolates with aza-o-quinodimethanes (aza-o-QMs) formed in situ is reported via a 1,4-elimination in the presence of tetramethylammonium fluoride (TMAF). The reaction partners were reacted to provide a wide variety of substituted 2-(tosylamino)dihydrochalcones in 45-97% yield in a single reaction sequence in one pot under mild condition. Additionally, various 2-(tosylamino)dihydrochalcones could be easily converted to form diverse heterocycles.[a] Dr.

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