Synthesis and reactivity of [ReBr 2(NCCH 3) 2(CO) 2] −: A new precursor for bioorganometallic chemistry

Abstract

We have synthesised (Et 4N)[ReBr 2(NCCH 3) 2(CO) 2] 1 in two steps from [ReBr 3(CO) 3] 2−. Complex 1 is water and air stable and the two Br − ligands are easily exchanged for coordinating solvent molecules such as water. The reactivity of 1 with several ligands such as imidazole (imz) and 2-picolinic acid (2-pic) are easily possible with substitution exclusively occurring in trans-position to the carbonyl groups. The resulting complexes [Re(imz) 2(NCCH 3) 2(CO) 2] + and [Re(2-pic)(NCCH 3) 2(CO) 2] have been isolated and structurally characterised. The two acetonitrile ligands are strongly bound and are not substituted under any conditions. Complex 1 represents therefore the new moiety “ trans, cis-[Re(NCCH 3) 2(CO) 2] +” which can be considered as a further building block in organometallic chemistry.