Regioselective magnesiations of functionalized arenes and heteroarenes using TMPMg in hydrocarbons.

We report the preparation of a new hydrocarbon-soluble magnesium amide TMPMg (TMP = 2,2,6,6-tetramethylpiperidyl). This base showed excellent properties for the regioselective magnesiation of various arenes and heteroarenes bearing ethyl esters and carbamates under very mild reaction conditions. Subsequent trapping with aryl iodides (Negishi cross-coupling) gave access to a range of highly functionalized valuable building blocks.

Directed regioselective ,'-magnesiations of aromatics and heterocycles using BuMg in toluene.

Aryl azoles are ubiquitous as bioactive compounds and their regioselective functionalization is of utmost synthetic importance. Here, we report the development of a toluene-soluble dialkylmagnesium base BuMg. This new reagent allows mild and regioselective -magnesiations of various -arylated pyrazoles and 1,2,3-triazoles as well as arenes bearing oxazoline, phosphorodiamidate or amide directing groups.