A green non-acid-catalyzed process for direct N=N-C group formation: comprehensive study, modeling, and optimization

Area of Science:

• Organic Chemistry
• Catalysis
• Green Chemistry

Background:

• Traditional methods for N=N-C bond formation often require harsh acidic conditions.
• Developing milder, non-acid-catalyzed alternatives is crucial for sustainable synthesis.

Purpose of the Study:

• To introduce and optimize a new non-acid-catalyzed system for direct N=N-C bond formation.
• To model and determine optimal reaction conditions using statistical methods.

Main Methods:

• Utilized sodium nitrite as a nitrosonium source and triethylammonium acetate (TEAA) in a non-acidic medium.
• Employed response surface methodology for modeling and optimization of reaction parameters (sodium nitrite, TEAA, water).
• Validated the optimized conditions through experimental analysis and electrochemistry studies.

Main Results:

• A second-order polynomial model accurately predicted reaction yield (R²=0.93, F=35.7, P=0.0001).
• Optimal conditions determined: 2.2 mmol sodium nitrite, 2.2 mL TEAA, 0.5 mL water at room temperature.
• The method demonstrated a broad scope, high yields, short reaction times, and mild conditions.

Conclusions:

• Successfully developed and optimized a novel, non-acid-catalyzed direct N=N-C bond formation reaction.
• The established model provides reliable predictions for reaction outcomes.
• The method offers a greener and more efficient alternative for synthesizing compounds with N=N-C linkages.