Imido analogues of the tungstate(VI) and perrhenate(VII) ions. X-Ray crystal structures of Li2W(NBut)4 and Li(tmed)Re(NBut)4

Abstract

The first homoleptic imido compounds of transition metals, namely the imido analogues of the tungstate, WO₄^2–, and perrhenate, ReO₄^–, anions have been obtained as the lithium salts, Li₂W(NBu^t)₄and Li(tmed)Re(NBu^t)₄; the structure of the tungsten compound contains two W(NBu^t)₄ units linked by N ⋯ Li ⋯ N bridges while that of the rhenium compound shows the lithium co-ordinated to N atoms of tetramethylethylenediamine and to two N atoms of the anion.