Visible-light-driven EDA complex-promoted cascade cyclization to construct 4-cyanoalkyl isoquinoline-1,3-diones

Area of Science:

• Organic Chemistry
• Photocatalysis
• Synthetic Methodology

Background:

• Visible-light photocatalysis offers a sustainable approach to organic synthesis.
• Cycloketone oxime esters are versatile precursors for generating reactive intermediates.
• Developing efficient methods for synthesizing cyanoalkylated products and heterocycles remains a key challenge.

Purpose of the Study:

• To develop a novel visible-light-induced photocatalytic system.
• To synthesize various cyanoalkylated products and heterocyclic compounds.
• To explore the utility of EDA complex formation in photocatalysis.

Main Methods:

• Visible-light irradiation was used to initiate the reaction.
• Electron donor-acceptor (EDA) complex formation was employed as a key strategy.
• Cycloketone oxime esters reacted with N-methacryloyl benzamides in the presence of a photocatalyst.
• Mechanistic studies were conducted to elucidate the reaction pathway.

Main Results:

• A range of cyanoalkylated products were synthesized with N-methacryloyl benzamides.
• Diverse heterocyclic compounds were obtained, demonstrating broad substrate compatibility.
• The formation of an EDA complex was confirmed as crucial for the photocatalytic process.
• High yields of 4-cyanoalkyl isoquinoline-1,3-diones were achieved using 1,4-diazabicyclo[2.2.2]octane (DABCO).

Conclusions:

• A practical and efficient visible-light-driven photocatalytic method was established.
• The reaction provides a valuable route for synthesizing complex cyanoalkylated molecules and isoquinoline-1,3-diones.
• The EDA complex-promoted strategy offers a new avenue for photocatalytic transformations.