Structural characterization of ferromagnetic bridged-acetato and -dichlorido copper(II) complexes based on bicompartmental 4-t-butylphenol

Synthesis, structure and magnetic characterization of dinuclear copper(ii) complexes bridged by bicompartmental phenolate

“…1,2 The second category of the bicompartmental phenolate ligands is the doubly bridged complexes where in addition to the bridged phenoxido group, an extra bridge exists and this was observed here in this study in complexes [Cu 2 (m-L R -O)(m-X)] +/2+ {1: X ¼ OH À , 2: X ¼ pz À and 3: X ¼ O 2 P(OC 6 H 5 ) 2 À } and in some other related complexes 6-9 {R ¼ CH 3 /t-Bu, X ¼ OH À , OAc À ; R ¼ t-Bu, X ¼ OCH 3 À }. 4,28,34,47 In this case moderate ferromagnetic to very strong antiferromagnetic coupling was observed.…”

“…4,28,34,47 In this case moderate ferromagnetic to very strong antiferromagnetic coupling was observed.…”

“…Careful inspection of literature showed that there are only four other examples similar to ours where the magnetic properties were studied for copper(II) dimers containing both L R -OH and X ligands (Chart 1), namely [Cu 2 (m-L Me O)(m-OH)](ClO 4 ) 2 $THF (6), 28 [Cu 2 (m- 9) 47 with J mag ¼ À224, À312, À80, +30.8 cm À1 , respectively. The reported J mag values were scaled according to the spin Hamiltonian denition in eqn (1).…”

Magnetostructural Properties of Some Doubly-Bridged Phenoxido Copper(II) Complexes

“…Dinuclear copper(II) complexes in which the Cu(II) ions are bridged by a phenolate oxygen atoms (L-O) and an exogenous bridging atom X with the coordination core Cu(µ-L-O)(µ-X) Cu (X = L-O, OH − , OR − , O 2− , OAc − , N 3 − and Cl − ) have been reported for a number of ligands with different skeletons frames [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ]. Some of these complexes have served as cooperative model systems to mimic the active sites in metalloproteins, such as hemocyanin [ 12 , 13 , 14 , 15 , 16 ], metalloenzymes, such as tyrosinase [ 16 , 17 , 18 ], galactose oxidase (GOase) [ 19 , 20 , 21 , 22 , 23 , 24 ], superoxide dismutase (SOD) [ 25 , 26 , 27 ], and as artificial nucleases for promoting the cleavage of DNA [ 5 , 6 , 28 , 29 ] as well as anticancer agents [ 30 , 31 ].…”

“…Different strategies have been employed in the design of this class of compounds. The first approach was achieved though the interaction Cu(II) salts with tridentate ligand-based phenolates in their skeletons [ 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ], and the second approach was via the design of bicompartmental phenolates bearing two pendent arms of N-donor groups [ 1 , 2 , 3 , 4 , 5 , 6 , 42 , 43 ]. A third approach was also used through the design of tripodal pyridyl tetradentate ligands containing one or two phenolate arms [ 12 , 14 , 15 , 20 , 29 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ].…”