Application of 108-47-4, In homogeneous catalysis, catalysts are in the same phase as the reactants. Enzymes are biological catalysts that produce large increases in reaction rates and tend to be specific for certain reactants and products. 108-47-4, Name is 2,4-Dimethylpyridine, molecular formula is C7H9N. In a Article，once mentioned of 108-47-4
Living polymerization of (o-(trimethylsilyl)phenyl)acetylene by molybdenum imido alkylidene complexes
syn-Mo(CHCMe2Ph)(NAd)[OCH(CF3)2]2(2,4-lutidine) (2a; Ad = 1-adamantyl) is a distorted trigonal bipyramid in which 2,4-lutidine occupies an axial position, a structure that results from addition of 2,4-lutidine to the CNO face of unstable pseudotetrahedral syn-Mo(CHCMe2Ph)(NAd)[OCH(CF3)2]2. 2a reacts with (o-(trimethylsilyl)phenyl)acetylene (o-TMSPA) solely via formation of an alpha-substituted metallacyclobutene intermediate (alpha addition) that opens to give a single rotamer of a disubstituted alkylidene complex. o-TMSPA is smoothly polymerized at a rate k(2a)[2a]0[o-TMSPA] when [2a] < 1 mM with a propagation rate constant k(2a) = 0.30 s-1 M-1. Additional studies confirmed that the disubstituted alkylidene propagating species is essentially base-free (K(2a) = 62 M-1) and that the propagating species is stable under catalytic conditions (25C). Other versions of the Mo(CHCMe2Ph)(NAd)[OCH(CF3)2]2(base) catalyst are either inactive (base = pyridine) or unstable (base = 2-(3-pentyl)pyridine). Mo(CHCMe2Ph)(NAr')(OC6F5)2(quinuclidine) (7; Ar' = 2,6-Me2C6H3) will also react smoothly with (o-(trimethylsilyl)phenyl)acetylene to give poly(o-TMSPA) with K7 = 1380 M-1 and k7 = 0.23 s-1 M-1. Low-polydispersity polyenes containing up to 150 equiv of o-TMSPA can be obtained readily using either catalyst. The thermodynamically most stable form of poly(o-TMSPA), which contains ~25 double bonds, is air-sensitive and has a significantly red-shifted lambda(max). o-t-BuPA also can be polymerized to give highly conjugated polyenes, but o-iPrPA, o-MePA, and phenylacetylene itself add to initiator 2a with decreasing alpha regiospecificity (73%, 60%, and 56%, respectively). A lack of regiospecificity we propose leads to polymers that do not have a pure head-to-tail structure, have a lower degree of conjugation, and have a progressively more blue-shifted lambda(max).
Catalysts are substances that increase the reaction rate of a chemical reaction without being consumed in the process. In my other articles, you can also check out more blogs about 108-47-4
Reference：
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