Enantioselective Phosphine-Catalyzed Trimerization of γ-Aryl-3-butynoates via Isomerization/[3 + 2] Cyclization/Michael Addition Cascade.

We disclose an l-isoleucine-derived amide phosphine-catalyzed trimerization of γ-aryl-3-butynoates, which undergo an isomerization to allenoate, [3 + 2] cyclization, and Michael addition cascade. Exocyclopentene derivatives bearing an all-carbon quaternary stereocenter were constructed stereospecifically and enantioselectively. A wide variety of γ-aryl-3-butynoates could be employed to deliver optically pure cyclopentene derivatives in moderate to good yields with ee values of ≥95% and in most cases ≥98%.

Phosphine catalyzed [3+2] cyclization/Michael addition of allenoate with CS2 to form 2-thineyl vinyl sulfide.

We have developed a DPPE-catalyzed three molecular two component tandem reaction of γ-substituted allenoate and CS2 to construct 2-thineyl vinyl sulfide through phosphine catalyzed [3+2] cyclization followed by Michael addition. The synthetic value of the 2-thineyl vinyl sulfide was demonstrated by a concise synthesis of an anti-glaucoma agent.

A copper-catalyzed three component reaction of aryl acetylene, sulfonyl azide and enaminone to form iminolactone via 6π electrocyclization.

We developed a copper-catalyzed three component reaction of aryl acetylene, enaminone and sulfonyl azide to construct iminolactone via a cascade process involving copper-catalyzed alkyne-azide cycloaddition (CuAAC), Michael addition of metalated ketenimine followed by elimination and 6π electrocyclization.