The intramolecular click reaction using 'carbocontiguous' precursors

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Click Chemistry

Background:

• Intramolecular click reactions offer efficient pathways for constructing complex molecular architectures.
• Azidoalkynyl precursors are key building blocks in click chemistry, enabling the formation of triazole rings.
• Carbocontiguous linkers provide unique structural scaffolds for cyclization strategies.

Purpose of the Study:

• To synthesize and investigate carbocontiguous azidoalkynyl precursors for intramolecular click reactions.
• To explore the copper-catalyzed cyclization of these precursors to form novel fused triazole systems.
• To determine optimal reaction conditions for efficient cyclization and product formation.

Main Methods:

• Synthesis of novel carbocontiguous precursors bearing both azidoalkyl and ethynylmethyl functionalities.
• Copper-catalyzed intramolecular click reaction (cyclization) using various copper salts.
• Optimization of reaction conditions, including the use of CuSO4/sodium ascorbate system.

Main Results:

• Successful synthesis of carbocontiguous azidoalkynyl precursors.
• Copper-catalyzed cyclization yielded 1,4-disubstituted endo-fused triazole products with high efficiency (84-95%).
• Modification of the precursor allowed for the formation of a 1,5-disubstituted exo-fused triazole.

Conclusions:

• Carbocontiguous azidoalkynyl precursors are effective substrates for intramolecular click reactions.
• The CuSO4/sodium ascorbate system represents an optimal condition for efficient cyclization.
• This methodology provides a versatile route to diverse fused triazole structures.