Self-Supported Heterogeneous Star-Shaped Oxime-Palladacycle Catalysts for the Suzuki Coupling Reactions

Abstract

A novel strategy to synthesize heterogeneous star-shaped oxime-palladacycle catalysts, which exhibited good catalytic activity and recyclability in the Suzuki coupling of aryl bromides and chlorides, was described.

Key words

self-supported - palladacycle - heterogeneous - Suzuki coupling

References and Notes

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10

General Procedure for the Synthesis of Self-Supported Catalyst 3.
To a solution of Li₂PdCl₄ (116 mg, 0.44 mmol) and NaOAc (38.3 mg, 0.46 mmol) in MeOH (4 mL) was added a solution of the corresponding star-shaped oxime 2 (0.49 mmol) in MeOH (4 mL). Brown solid precipitated from the solution in about half an hour. After stirring at r.t. for 1 d, the mixture was further stirred at 40 °C for 48 h. The mixture was filtered and washed thoroughly with H₂O, MeOH and acetone. The solid was dried under high vacuum at 50 °C for 10 h. The Pd loading was determined by ICP analysis.