Silica Gel-Promoted Tryptamine-Ynamide Cyclization Strategy Enabling Total Synthesis of Elacomine

Key Points

• The study reveals total synthesis of elacomine via a 5-step process, with cyclization as the key transformation.
• A unique pH-dependent tautomerism of elacomine was uncovered, supported by pH-responsive NMR observations.
• Silica gel significantly promotes the cyclization of tryptamine-ynamide, streamlining the synthesis process.
• This work highlights the importance of silica gel in facilitating complex organic transformations in synthesis.