Regioselective Magnesiations of Fluorinated Arenes and Heteroarenes Using Magnesium-bis-Diisopropylamide (MBDA) in Hydrocarbons

Abstract

We report a convenient preparation of a new and storable magnesium amide (iPr2N)2Mg (magnesium-bis-diisopropylamide; MBDA) which proved to be especially suitable for the non-cryogenic magnesiation of fluoro-substituted arenes and heteroarenes providing arylmagnesium amides (ArMgDA) or bis-heteroaryl magnesiums (HetAr)2Mg in hydrocarbons. Further reactions with electrophiles (aldehydes, ketones, allylic bromides, aryl halides (Negishi cross-coupling)) furnished a range of polyfunctional fluoro-substituted unsaturated building blocks. Several postfunctionalizations were described as well as NMR-studies confirming the dimeric structure of the base.