Barrel- and Crown-Shaped Dodecanuclear Copper(II) Cages Built from Phosphonate, Pyrazole, and Hydroxide Ligands

Abstract

The reaction of Cu(ClO4)2. 6H2O with t-BuP(O)(OH)2 and 3,5-(CF3)2PzH in the presence of triethylamine afforded the dodecanuclear cage ([Et3NH]2[Cu12(mu-3,5-(CF3)2Pz)6(mu3-OH)6(mu-OH)3(mu3-t-BuPO3)2(mu6-t-BuPO3)3][t-BuPO2OH][C6H5CH3]2) (2). The molecular structure of this cage revealed that it possesses a barrel-shaped architechture. The cage structure is built by the cumulative coordination action of phosphonate, hydroxide, and pyrazolyl ligands. A similar reaction involving Cu(NO3)2. 3H2O, t-BuP(O)(OH)2, 3,5-dimethylpyrazole, and triethylamine afforded another dodecanuclear cage [Cu12(mu-DMPz)8(eta1-DMPzH)2(mu4-O)2(mu3-OH)4(mu3- t-BuPO3)4].3MeOH (3). The latter is crown-shaped and is built by the coordination of pyrazole, pyrazolyl, phosphonate, hydroxide, oxide, and methanol ligands. Both of the dodecanuclear cages are efficient nucleases in the presence of magnesium monoperoxyphthalate.

Coordination Versatility of Pyrazole‐Based Ligands towards High‐Nuclearity Transition‐Metal and Rare‐Earth Clusters

“… Molecular structure of the neutral compound [(Cu 12 L1l) 6 (μ 3 ‐OH) 6 (μ‐OH) 3 (μ 3 ‐ t BuPO 3 ) 2 (μ 6 ‐ t BuPO 3 ) 3 ] 104…”

Polynuclear copper(II) complexes of di-2-pyridyl ketone derivatives and tert-butylphosphonic acid: crystal structures and magnetic behaviour

“…1-10 However, recently it has been established that by using organophosphonates bearing a bulky R group in combination with ancillary ligands, such as pyrazoles and pyridines, it is possible to prepare discrete transition metal organophosphonate derivatives. 11- 35 A good example are the anionic derivatives of the tert-butylphosphonic acid, t BuPO 3 Hand t BuPO 3 2-, which have been used as ligands with transition metals to obtain several types of clusters with different metals and variable nuclearities: [25][26][27][28][29][30][31][32][33][34] Cu 12 , Co 12 , Cu 10 , Cu 4 , Co 4 , Mn 5 , Mn 4 , Fe 4 , Fe 10 , Mn 20 . The t BuPO 3 Hand t BuPO 3 2ligands show different coordination modes in this series of cluster compounds, 25-34 (Scheme 1).…”

2,6-(Diphenylmethyl)-Aryl-Substituted Neutral and Anionic Phosphates: Approaches to H-Bonded Dimeric Molecular Structures

“…In the case of phosphonic acids there have been some studies that correlate to the product formation vis‐à‐vis the steric encumbrance of the phosphonic acid. For instance, barrel‐ and crown‐shaped dodecanuclear copper(II) cages were built from t BuP(O)(OH) 2 whereas tetranuclear copper(II) cages result from 2,4,6‐ i Pr 2 C 6 H 3 P(O)(OH) 2 …”