Complex halides of transition metals. Part XII. The preparation, characterization, and reactivity of the pentachlororhenate(IV) anion

Abstract

The reaction of rhenium(V) chloride with 1 : 1 mole proportions of tetraethyl- or tetra-n-propyl-ammonium chlorides in dichloromethane under anhydrous, oxygen-free conditions, affords the rhenium(IV) species of stoicheiometry [R₄N]ReCl₅ which contain the polymeric octahedral [ReCl₅^–]_n anion. The air-stable salts react with a variety of monodentate donor molecules (e.g. acetonitrile and pyridine) and with pyrazine (pz) to produce the pseudooctahedral anions [ReCl₅,L]^–. The pyrazine-bridged complex ([Et₄N]ReCl₅)₂,pz has also been prepared.