Effects of Concentration of Some Lanthanide(III) Complexes of 1,7‐Bis(carboxymethyl)‐1,4,7,10‐tetraazacyclododecane on Bis(p‐nitrophenyl)phosphate Hydrolysis

Abstract

A detailed study of the effects of the concentration of some lanthanide(III) complexes [LnDO2A + ; DO2A = 1,7-bis(carboxymethyl)-1,4,7,10-tetraazacyclododecane] on the hydrolysis of the phosphodiester bond of the compound BNPP [sodium bis(4-nitrophenyl)phosphate] is reported at 25°C and pH 7.90 (Ln = Eu), 9.35 (Ln = Eu), and 9.90 (Ln = Eu, Er and Yb). The reaction is found to be first order with respect to BNPP concentration at pH 7.90 and 9.35 and to increase to 1.78 Ϯ 0.09, 1.64 Ϯ 0.07, and 1.63 Ϯ 0.09 with respect to [EuDO2A + ] concentration at pH 7.90, 9.35, and 9.90, respectively, thereby indicating that dinuclear species are involved in the reactions. Similar observations were found for the other two LnDO2A + complexes at pH 9.90 [1.63 Ϯ 0.11 (Er) and 1.49 Ϯ 0.09 (Yb)]. The k obs data obtained by the initial

Dinuclear Lanthanide(III)‐m‐ODO2A‐dimer Macrocyclic Complexes: Solution Speciation, DFT Calculations, Luminescence Properties, and Promoted Nitrophenyl‐Phosphate Hydrolysis Rates

“…The previously reported procedures were followed with minor modifications . The Ln 2 ( m ‐ODO2A‐dimer) complex solutions were freshly prepared by mixing 2.00:1.01 metal salt to ligand molar ratio solutions.…”

“…Previously we reported the effects of pH, metal ionic radii, number of coordinated water molecules, charge and concentrations of a number of macrocyclic LnDO2A + (DO2A=1,7‐bis(carboxymethyl)‐1,4,7,10‐tetraazacyclododecane, H 2 L′) complexes potentially useful as artificial nucleases . In particular, the effects of the concentration of some LnDO2A + on BNPP hydrolysis were reported in detail at pH 7.90, 9.35, and 9.90 and it was proposed that the dinuclear species, that is, the mono‐hydroxo‐bridged {Ln 2 L′ 2 (μ‐OH)(OH)(H 2 O) 3 } and the di‐hydroxo‐bridged {Ln 2 L′ 2 (μ‐OH) 2 (H 2 O) 2 } were potentially more reactive for promoting BNPP hydrolysis . Unfortunately, the sluggish complex formation and dissociation kinetic behavior of the macrocyclic LnDO2A + complexes, particularly at higher pH at which dinuclear species were more likely to form, prevented more detailed speciation studies to establish the structure–reactivity relationship.…”

Poly[[μ-bis(4-nitrophenyl) phosphato-κ2O,O′]sodium]

“…For hydrolytic cleavage of the phosphodiester bond in bis(pnitrophenyl)phosphate (BNPP) and related systems, see: Belousoff et al (2009); Branum et al (2001); Chang et al (2009); Liu et al (2004); Mancin et al (2005); Oh et al (1996); Sredhera & Cowan (2001). For crystal structures containing the BNPP entity, see: Bazzicalupi et al (2004); Bond et al (1985); Fry et al (2003); Jurek & Martell (1999); Krá l et al (2006); Pletcher et al (1972); Sax et al (1970Sax et al ( , 1971; Warden et al (2005); Yoo et al (1975).…”

“…For this reason the bis(p-nitrophenyl)phosphate anion is a popular model substrate for kinetic studies of the hydrolytic cleavage of the phosphodiester bond similar to DNA (Chang et al, 2009;Oh et al, 1996).…”

Size Selectivity in Heterolanthanide Molecular Complexes with a Ditopic Ligand

“…The electronic configuration of lanthanide ions, featuring a 4f incomplete shell shielded from the interaction with the surrounding chemical species, makes them appealing for the development of functional materials with several fields of applicability (luminescence, magnetism, catalysis, among the others). [ 1 , 2 ] On this regard, the coexistence of different lanthanide ions in the same context has been frequently sought to prepare multifunctional materials [3] with tuneable properties in luminescence,[ 4 , 5 , 6 , 7 , 8 , 9 , 10 ] magnetism[ 11 , 12 , 13 , 14 , 15 ] and catalysis,[ 16 , 17 , 18 ] featuring potential applications for dual emissions and up‐conversion,[ 19 , 20 , 21 , 22 , 23 , 24 ] multiple signal detection, [25] barcoded materials,[ 26 , 27 ] bioimaging nanoprobes,[ 28 , 29 ] and as units of information for quantum computation. [30] However, the similarity in chemical reactivity across the series and their high kinetic lability make the separation of lanthanide ions, as well as the preparation of ordered hetero‐lanthanide systems, challenging.…”