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The C2-sym. electron-poor ligand (R)-BINOP-F (4; (R)-2,2'-[bis(pentafluorophenyl)phosphinoxy]-1,1'-binaphthalene) was prepd. by reaction of (R)-BINOL ((R)-1,1'-binaphthalene-2,2'-diol) with bromobis(pentafluorophenyl)phosphine in the presence of NEt3. The iodo complex [CpRu((R)-BINOP-F)(I)] ((R)-6) was obtained by substitution of two carbonyl ligands by (R)-4 in the in situ-prepd. [CpRu(CO)2H] complex followed by reaction with iodoform. Complex 6 was reacted with [Ag(SbF6)] in acetone to yield [CpRu((R)-BINOP-F)(acetone)][SbF6] ((R)-7). X-ray structures were obtained for both (R)-6 and (R)-7. The chiral 1-point binding Lewis acid [CpRu((R)-BINOP-F)][SbF6] derived from either (R)-7 or the corresponding aqua complex (R)-8 activates methacrolein and catalyzes the Diels-Alder reaction with cyclopentadiene to give the [4 + 2] cycloadduct with an exo/endo ratio of 99:1 and an ee of 92% of the exo product. Addn. occurs predominantly to the methacrolein Calpha-Re face. In soln., H2O in (R)-8 exchanges readily. Moreover, a 2nd exchange process renders the diastereotopic BINOP-F P atoms equiv. These processes were studied by the application of variable-temp. 1H, 31P, and 17O NMR spectroscopy, variable-pressure 31P and17O NMR spectroscopy, and, using a simpler model complex, d. functional theory (DFT) calcns. The results point to a dissociative mechanism of the aqua ligand and a pendular motion of the BINOP-F ligand. NMR expts. show an energy barrier of 50.7 kJ mol-1 (12.2 kcal mol-1) for the inversion of the pseudo-chirality at the Ru center. [on SciFinder (R)]

he structure and dynamics of the surrounding water were studied through molecular dynamics (MD) simulations for several GdIII polyaminocarboxylate and polyaminophosphonate complexes in aqueous solution. The radial distribution functions (rdf) show that a few water molecules are bonded to the ligand through hydrogen bonds to hydrophilic groups such as carboxylates and phosphonates. Residence times are of the order of 20-25 ps for the polyaminocarboxylate and 56 ps for the polyaminophosphonate chelates. No preferred orientation or bonding of water molecules is observed in the hydrophobic region of the anisotropic macrocyclic complexes. Our rdf allow calculation of the outer-sphere contribution to the nuclear magnetic resonance dispersion (NMRD) profiles using Freed's finite differences method, including electronic relaxation. The results show that the commonly used analytical force-free model is only an empirical relationship. When experimental outer-sphere NMRD profiles are available ([Gd(teta)]- and [Gd(dotp)]5- (teta= N,N,N,N-tetracarboxymethyl-1,4,8,11-tetraazacyclotetradecane; dotp=N,N,N,N-tetraphosphonatomethyl-1,4,7,10-tetraazacyclododecane) the calculated curves are in good agreement. In the case of [Gd(teta)]-, the comparison with the experimental NMRD profile has led us to predict a very fast electronic relaxation, which has been confirmed by the EPR spectrum.

Taking advantage of the Curie contribution to the relaxation of the protons in the Tb(III) complex, and the quadrupolar relaxation of the 17O and 2H nuclei on the Eu(III) complex, the effect of the internal motion of the water molecule bound to [Ln(DOTAM)(H2O)]3+ complexes was quantified. The determination of the quadrupolar coupling constant of the bound water oxygen X_O(1 + eta_O^2/3)1/2 = 5.2 ± 0.5 MHz allows a new analysis of the 17O and 1H NMR data of the [Gd(DOTA)(H2O)]- complex with different rotational correlation times for the Gd(III)-Owater and Gd(III)-Hwater vectors. The ratio of the rotational correlation times for the Ln(III)-Hwater vector and the overall rotational correlation time is calculated tauRH/tauRO = 0.65 ± 0.2. This could have negative consequences on the water proton relaxivity, which we discuss in particular for macromolecular systems. It appears that the final effect is actually attenuated and should be around 10% for such large systems undergoing local motion of the chelating groups.

The invention relates to a novel class of ligands, complexes comprising such ligands and a metal ion, and adducts of these metal complexes and a macromolecule. Pharmaceutical compositions and methods of making and using the ligand-metal complexes are also described. The invention also relates to the use of macromolecular adducts for enhancement of diagnostic imaging. In particular, the invention relates to (ethylene)-(propylene)-triaminepentaacetic acid (EPTPA) derivatives, a process for their production, and their use for the production of pharmaceutical agents for NMR diagnosis or radiodiagnosis or radiotherapy.

High‐pressure 1H‐NMR. has been used to determine volumes of activation (ΔV #) for solvent exchange with [M(S)6]3+ ion (M = Al(III), Ga(III); S = dimethylsulfoxide (DMSO) and N,N‐dimethylformamide (DMF)) in [2H]3‐nitromethane solution. For Al(III),Δ V # = + 15.6 ± 1.4 (S = DMSO, 358.5 K) and ΔV # = + 13.7 ± 1.2 cm3mol−1 (S = DMF, 354.5 K), whilst for Ga(III), ΔV # = + 13.1 ± 1.0 (S = DMSO, 334.6 K) and ΔV # = +7.9 ± 1.6 cm3mol−1 (S= DMF, 313.8 K). Variable temperature studies over a temperature range of 107.2 K (Al(III)) and 101.1 K (Ga(III)) were carried out for solvent exchange with [M(DMF)6]3+ ions in [2H]3‐nitromethane solution, using stopped‐flow NMR, and conventional linebroadening, and gave ΔH # = 88.3 ± 0.9 and 85.1 ± 0.6 kJ+ mol−1, and ΔS # = 28.4 ± 2.7 and 45.1 ± 1.9 JK−1 mol−1 for Al(III) and Ga(III) ions respectively. All of these results are consistent with dissociative modes of activation.