In homogeneous catalysis, catalysts are in the same phase as the reactants. Chemistry is traditionally divided into organic and inorganic chemistry. COA of Formula: C7H9N, Catalysts allow a reaction to proceed via a pathway that has a lower activation energy than the uncatalyzed reaction. In an article，Which mentioned a new discovery about 108-47-4
Acid dissociation, as well as cationic homo- and heteroconjugation constants have been determined by potentiometric titration in systems involving substituted pyridines and conjugate cationic acids in the polar protophobic aprotic solvent acetone and in polar amphiprotic methanol. The values of the constant were compared with those previously determined in other polar protophobic aprotic solvents, acetonitrile, nitromethane and propylene carbonate. The pK(a) values of the protonated pyridine derivatives in acetone range between 2.69 and 12.69 and are on average 2-3 orders of magnitude higher than those determined in water. The pK(a) values in methanol vary between 1.02 and 10.37, and are only slightly higher than those in water, the difference not exceeding one order of magnitude. A comparison of the acid dissociation constants determined in all the non-aqueous solvents considered shows that the strength of the cationic acids increases on going from acetonitrile through nitromethane, propylene carbonate and acetone to methanol. In almost all systems of the type: a pyridine derivative its conjugate acid, the cationic homoconjugation equilibrium is present in acetone (1.60
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Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis—I. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis