A groundbreaking mixed donor diamido-diarsine [As2N2] macrocyclic ligand that coordinates to a series of early transition metals (ETMs) has been designed

Arsine ligands are rare and this is the first time a complex with an yttrium-arsenic bond has been made.

In earlier experiments, Michael Fryzuk and his group at the University of British Columbia, Canada, successfully synthesised a mixed donor [P2N2] macrocyclic system. This is remarkably versatile as it coordinates to dinitrogen as well as a diverse range of metals.

Progress has now been made by exchanging the phosphorus atoms for arsenic in an attempt to alter the reactivity of the ETM complexes.

Future investigations will delve into the chemistry of [As2N2] with late transition metals, while the effects of adding different functionalities to other ligands in the complexes may be pursued.

The main challenge will be to eliminate arsenic’s involvement in the ETM centres’ reactivity. Fryzuk says that ’intriguing chemistry could be induced without disrupting the arsenic donors.’

Kathryn Sear