Abstract:
Two homoleptic YbII constrained geometry complexes [Yb{η5,η1-R2P(C5Me4)NAd}2] [R =Me (3), Ph (4); Ad=1-adamantyl] derived from P-amino(cyclopentadienylidene)phosphoranes (CpPN) R2P(C5Me4)NHAd [R=Me (1), Ph (2)] were found to be remarkably stable towards dioxygen, as shown by NMR spectroscopy and further confirmed by the crystal structure analysis of 4 and discussed in terms of efficient steric shielding and electronic stabilization of the YbII metal centre by this CpPN ligand type.