A catalyst don’t appear in the overall stoichiometry of the reaction it catalyzes, but it must appear in at least one of the elementary reactions in the mechanism for the catalyzed reaction. 224311-51-7, Name is 2-(Di-tert-Butylphosphino)biphenyl, molecular formula is C20H27P. In a Article£¬once mentioned of 224311-51-7, Recommanded Product: 2-(Di-tert-Butylphosphino)biphenyl
Cationic Cp?-Ruthenium Catalysts for Metal-Catalyzed Living Radical Polymerization: Cocatalyst-Independent Catalysis Tuned by Counteranion
We present the cationic Cp?-ruthenium complexes [Cp?Ru(CH3CN)(PPh3)2A; A-: the counteranion; abbreviated Cp?Ru+A-] as the active, cocatalyst-free, and tunable catalysts for metal-catalyzed living radical polymerization (Mt-LRP). A PF6-based cationic complex in conjunction with a alkyl halide initiator led to controlled polymerization of methyl methacrylate (MMA) giving well-controlled PMMAs with narrow molecular weight distribution (Mw/Mn < 1.10) at appropriate polymerization rate (conversion >80% in 15 h), although cocatalyst was not combined. The catalytic feature was clearly different from the neutral counterpart [Cp?RuCl(PPh3)2: Cp?Ru], resulting in retarded polymerization under the cocatalyst-free condition. Interestingly, the catalytic activity was influenced by the counteranions. For example, the PF6-based complex did not afford catalysis for controlled polymerization of methyl acrylate (MA), but an Sb6-based [Cp?Ru(CH3CN)(PPh3)2SbF6: Cp?Ru+SbF6-] allowed control of the polymerization. Model reaction analysis revealed the unique transformation of cationic complex through activation process for carbon-halogen bond: weakly coordinated solvent (e.g., CH3CN) is likely to be eliminated to give a 16e complex instead of the neutral phosphine ligand (e.g., PPh3). Indeed, bipyridine (bipy), which could coordinate tighter than PPh3, was acceptable as ligand for the cationic complex to control radical polymerization, in sharp contrast to with the neutral counterpart requiring ligand elimination for the activation process.
Balanced chemical reaction does not necessarily reveal either the individual elementary reactions by which a reaction occurs or its rate law.Recommanded Product: 2-(Di-tert-Butylphosphino)biphenyl. In my other articles, you can also check out more blogs about 224311-51-7
Reference£º
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate