A Green Alternative for Aryl Iodide Preparation from Aromatic Amines
Zohreh Shahnavaz1, Lia Zaharani1, Mohd Rafie Johan1
1Nanotechnology & Catalysis Research Center, Institute of Postgraduate Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Current Organic Synthesis
|February 5, 2020
Summary
This study presents a safe and cost-effective one-pot synthesis for aryl iodides using saccharin salts. The developed method avoids hazardous intermediates and is metal-free, offering a greener approach to organic synthesis.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Arene diazonium salts are crucial intermediates in organic synthesis.
- The instability of dry arene diazonium salts poses significant safety hazards.
Purpose of the Study:
- To develop a safe and efficient one-pot synthesis of aryl iodides.
- To utilize saccharin salts as stable intermediates for diazotization.
Main Methods:
- In situ preparation of arene diazonium saccharin salts from aryl amines and tert-butyl nitrite (TBN) with saccharin (Sac-H).
- Telescopic reaction protocol involving direct diazotization of the in situ generated intermediates without isolation.
- Employing TBN, Sac-H, glacial acetic acid, and tetraethylammonium iodide (TEAI) for aryl iodide synthesis.
Main Results:
- Successful synthesis of a variety of aryl iodides.
- A greener and low-cost synthetic methodology was established.
- The reaction proceeds efficiently under mild conditions.
Conclusions:
- A safe, cost-effective, and metal-free one-pot method for aryl iodide synthesis is presented.
- The methodology offers a broad substrate scope and utilizes readily available, stable reagents.
- Partial recovery of saccharin and tetraethylammonium cation minimizes waste and reduces costs.
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