found: Work cat.: Butler, J.M. Structural characterization of cation-binding metallacrown ethers and applications in rhodium-catalyzed hydroformylation, 2004:leaf 2 (A metallacrown ether is formed when an [alpha], [omega]-bis(phosphorus-donor)polyether ligand chelates to transition metals)
found: Chemical communications (Cambridge, England), 1998:p. 2771 (Metallacrown ethers are a class of molecular receptors with both crown ether- and transition metal-receptor sites)
found: Journal of organometallic chemistry, May 31, 1999:p. 328 (Metallacrown ethers are formed when [alpha],[omega]-bis(phosphorus-donor)polyether ligands chelate soft transition metals. These complexes bind alkali metal cations to form hard-soft bimetallic complexes with the strength of the binding depending on both the ring size and conformation)
found: Organometallics, Aug. 3, 1998:p. 3550 (Metallacrown ethers are a unique class of transition-metal complexes that are formed when [alpha],[omega]-bis(phosphorus donor)-polyether ligands chelate transition metals)
