Turning a "useless" ligand into a "useful" ligand: a magneto-structural study of an unusual family of Cu(II) wheels derived from functionalised phenolic oximes

Jamie M Frost, Robert J Stirling, Sergio Sanz, Nidhi Vyas, Gary S Nichol, Gopalan Rajaraman, Euan K Brechin

Research output: Contribution to journalArticlepeer-review

Abstract

While the phenolic oximes (R-saoH2) are well known for producing monometallic complexes of the type [M(II)(R-saoH)2] with Cu(II) ions in near quantitative yield, their derivatisation opens the door to much more varied and interesting coordination chemistry. Here we show that combining the complimentary diethanolamine and phenolic oxime moieties into one organic framework (H4L1 and H4L2) allows for the preparation and isolation of an unusual family of [Cu(II)]n wheels, including saddle-shaped, single-stranded [Cu(II)8] wheels of general formula [Cu8(HL1)4(X)4](n)[Y] (when n = 0, X = Cl(-), NO3(-), AcO(-), N3(-); when n = 2+ X = (OAc)2/(2,2'-bpy)2 and Y = [BF4]2) and [Cu8(HL2)4(X)4] (X = Cl(-), Br(-)), a rectangular [Cu6(HL1)4] wheel, and a heterometallic [Cu4Na2(HL1)2(H2L1)2] hexagon. Magnetic studies show very strong antiferromagnetic exchange between neighbouring metal ions, leading to diamagnetic ground states in all cases. DFT studies reveal that the magnitude of the exchange constants are correlated to the Cu-N-O-Cu dihedral angles, which in turn are correlated to the planarity/puckering of the [Cu(II)]n rings.

Original languageEnglish
Pages (from-to)10177-10187
JournalDalton Transactions
Volume44
Issue number22
DOIs
Publication statusPublished - 9 Apr 2015

Fingerprint

Dive into the research topics of 'Turning a "useless" ligand into a "useful" ligand: a magneto-structural study of an unusual family of Cu(II) wheels derived from functionalised phenolic oximes'. Together they form a unique fingerprint.

Cite this