Phosphine-Catalyzed 3+3 Annulation of Electron-Deficient Enyne-Type Propargylic Carbonates with α-Cyano Ketones

Key Points

• This research aims to establish a phosphine-catalyzed reaction to synthesize γ-pyran derivatives from electron-deficient enyne-type propargylic carbonates and α-cyano ketones.
• Developed a novel phosphine-catalyzed [3+3] annulation reaction.
• Utilized electron-deficient enyne-type propargylic carbonates and α-cyano ketones.
• Created 1,2,3-butatriene phosphonium intermediates in situ.
• Achieved high yields of tetrasubstituted γ-pyran derivatives.
• Demonstrated the use of propargylic carbonates as phosphine acceptors in catalysis.
• Validated the formation of dielectrophilic intermediates.