Direct nucleophilic addition to N-alkoxyamides

Area of Science:

• Organic Chemistry
• Synthetic Chemistry

Background:

• Amide bond synthesis is reliable, but functionalizing amide carbonyl groups remains challenging due to their inherent stability.
• Existing methods often require multiple steps or harsh conditions for amide carbonyl group modification.

Purpose of the Study:

• To develop a direct and efficient method for the functionalization of amide carbonyl groups.
• To enable the synthesis of multisubstituted amines through a one-pot reaction sequence.

Main Methods:

• Developed a direct nucleophilic addition reaction using N-alkoxyamides.
• Employed diisobutylaluminum hydride (DIBAL-H) or organolithium reagents as the first nucleophile.
• Utilized allylation, cyanation, or vinylation as the second nucleophilic addition.

Main Results:

• Successfully installed two different functional groups onto amide carbonyl groups in a single pot.
• The N-alkoxy group facilitated activation and prevented over-addition of the first nucleophile via chelation.
• Achieved high yields, including for sterically hindered α-trisubstituted amines, with a broad substrate scope (amides, lactams, macrolactams).

Conclusions:

• The developed method provides a practical and versatile approach for amide carbonyl functionalization.
• This strategy offers a significant advancement in the synthesis of complex amine structures.
• The N-alkoxyamide serves a dual role in activating the amide and controlling reactivity.