Synthetic Strategy for AB₂-Type Arsines via Bidentate Dithiolate Leaving Groups

Area of Science:

• Organometallic Chemistry
• Catalysis
• Synthetic Chemistry

Background:

• Arsenic ligands are underutilized in transition-metal catalysis despite their potential.
• Existing synthetic methods for arsenic ligands are limited, hindering diversification.

Purpose of the Study:

• To develop an efficient synthetic methodology for AB2-type arsenic ligands.
• To create arsenic analogues of phosphorus-based Buchwald ligands.
• To evaluate the catalytic activity of novel arsenic ligands in cross-coupling reactions.

Main Methods:

• A novel synthetic route involving 1,2-benzenedithiol and tribromoarsine was employed.
• Sequential nucleophilic substitution reactions were performed to generate AB2-type arsines.
• The synthesized arsa-Buchwald ligands were tested in Suzuki-Miyaura cross-coupling reactions.

Main Results:

• An efficient method for synthesizing AB2-type arsines was established.
• Arsa-Buchwald ligands demonstrated catalytic activity comparable to established phosphorus ligands like SPhos.
• The arsenic analogue of SPhos exhibited enhanced activity and stability under open-air conditions.

Conclusions:

• The developed methodology provides access to a diverse range of AB2-type arsenic ligands.
• Arsa-Buchwald ligands represent a promising alternative to phosphorus ligands in Suzuki-Miyaura coupling.
• The superior performance of the SPhos arsenic analogue highlights the potential of arsenic in catalysis.