Microwave-Assisted Suzuki-Miyaura Reactions with an Insoluble Pyridine-Aldoxime Pd-Catalyst

Abstract

The preparation of a solid Pd(II)-precatalyst and its use in microwave-assisted Suzuki-Miyaura reactions in water is described. The precatalyst is obtained by treatment of 4-pyridine-aldoxime with Na₂PdCl₄ and is insoluble in organic solvents as well as in water. Its robustness under microwave conditions and its insolubility allows simple reuse in ‘teabags’.

Key words

Suzuki-Miyaura reactions - precatalyst - pyridine-aldoxime Pd-catalyst

References

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5

The Emrys^TM Optimizer from Personal Chemistry was used for all experiments described here.

6

The Suzuki-Miyaura reaction (according to Scheme [2] ) could be repeated at room temperature and was completed within one week to yield the coupling product in 93% isolated yield.

10

Yields of homo-coupled products were below 5%.