Catalytic synthesis of saturated azacycles using transborylation

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Catalysis

Background:

• Pyrrolidines are important nitrogen-containing heterocycles found in pharmaceuticals and natural products.
• Efficient and selective synthetic routes to substituted pyrrolidines are highly sought after in organic synthesis.

Purpose of the Study:

• To develop a novel, catalytic method for the synthesis of pyrrolidines.
• To explore the scope and limitations of the developed synthetic methodology.

Main Methods:

• Intermolecular cyclisation-homologation of azido-butenes.
• Utilized a sequence involving hydroboration, 1,2-metallate rearrangement, and B-N/B-H transborylation.
• Investigated the reaction with azido-propenes and azido-pentenes.

Main Results:

• Successfully synthesized pyrrolidines via a catalytic reaction sequence.
• Demonstrated tolerance of substitutions at the C1-C3 positions of azido-butenes.
• Observed the formation of an aza-bora heterocycle and a saturated azido-pentane boronic acid pinacol ester when extending the methodology.

Conclusions:

• A simple and catalytic synthesis of pyrrolidines has been achieved.
• The methodology is versatile and tolerates various substitutions.
• Further exploration is needed to fully understand the outcomes with azido-propenes and azido-pentenes.