Direct Preparation of Arylmanganese Bromides Using Active Manganese

Abstract

Arylmanganese compounds were easily prepared via the direct oxidative addition of Rieke manganese to aryl bromides under mild conditions. The resulting organomanganese reagents undergo coupling reaction with acid chlorides to give the corresponding ketones in moderate yields.

Notes

In typical preparation, lithium (9.68 mmol), naphthalene (1.48 mmol), and anhydrous manganese iodide (4.71 mmol) under argon were stirred in freshly distilled THF (10 mL) for 1h at room temperature

1,2-Dibromoethane was used to consume the remaining active manganese in the reaction mixture because Mn∗ was active to additional electrophile to give a homocoupling product

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