The reaction rate of a catalyzed reaction is faster than the reaction rate of the uncatalyzed reaction at the same temperature.15746-57-3, Name is Cis-Dichlorobis(2,2′-bipyridine)ruthenium(II), molecular formula is C20H16Cl2N4Ru. In a Article£¬once mentioned of 15746-57-3, COA of Formula: C20H16Cl2N4Ru
Metal-assisted racemization of the atropisomers of a E,A-binaphthyl skeleton via a syn transition state
Delta/A-(delta/lambda-1,1?-Biisoquinoline)bis(2,2?- bipyridine)ruthenium(II) bis(hexafluorophosphate) (2) exists as an ?3:1 mixture of its two diastereomeric forms in acetone solutions at 25 C. The major isomer, (Delta,delta/A,lambda)-2, crystallizes in the monoclinic space group C2/c with Z = 8, a = 29.12(1), b = 18.593(7), and c = 17.85(1) A, beta= 127.81(4), R = 0.053, and Rw = 0.062 at 25 C. As expected, the 1,1?-biisoquinoline ligand is nonplanar, which is a result of a transannular steric interaction between H8 and H8?. Diastereomerically pure samples of 2 were found to isomerize rapidly in solution at room temperature in the absence of light to give a thermodynamic mixture of the two diastereomers. The rate data for the latter equilibrium at 80 C are K = 2.89, k(6amaj?6amin) = 12.7(3) s-1, and k(6amin?6amaj) = 36.6(9) s-1. The activation parameters were determined in the temperature range of 50-90 C: DeltaH? (maj?min) = 68.7 kJ mol-1, DeltaS?(maj?min) = -21 J K-1 mol-1, DeltaH?(min?maj) = 66.1 kJ mol-1, and DeltaS?(min?maj) = -38 J K-1 mol-1. Spin saturation transfer (SST), spin inversion transfer (SIT), and two-dimensional exchange spectroscopy (2D EXSY) NMR experiments using 2 and its 2,2?-bipyridine-d8 analogue demonstrate that the interconversion of the two diastereomers is the result of an intramolecular process of C2 symmetry that does not change the cis/trans relationship between the 1,1?-biisoquinoline and 2,2?-bipyridine ligands. Irregular mechanisms that involve breaking just one of the ruthenium-isoquinoline bonds have been ruled out because the rate of isomerization of a water-soluble derivative of 2, Delta/A-(delta/lambda-1,1?-biisoquinoline)bis(2,2?-bipyridine) ruthenium(II)dichloride, is essentially the same in D2O containing 1 M LiCl (k(6amaj?6amin) = 5.7(2) s-1) and 1 M DC1 (k(6amaj?6amin) = 7.1(1) s-1) at 80 C. We therefore conclude that interconversion of the two diastereoisomers of 2 takes place by a regular mechanism that involves atropisomerization of the eta2-1,1?-biisoquinoline ligand via a syn transition state.
Note that a catalyst decreases the activation energy for both the forward and the reverse reactions and hence accelerates both the forward and the reverse reactions.COA of Formula: C20H16Cl2N4Ru, you can also check out more blogs about15746-57-3
Reference£º
Highly efficient and robust molecular ruthenium catalysts for water oxidation,
Catalysts | Special Issue : Ruthenium Catalysts – MDPI