Reference of 69861-71-8, Catalysts function by providing an alternate reaction mechanism that has a lower activation energy than would be found in the absence of the catalyst. In some cases, the catalyzed mechanism may include additional steps.In a article, 69861-71-8, molcular formula is C42H42P2Pd, introducing its new discovery.
Taking into consideration the model geometry of the macrocyclic hexaporphyrin 1 as a host molecule, the structure of a benzene-centered porphyrin trimer bearing pyridine rings at the apical positions has been designed with the aim to use the latter as a template for the synthesis of its own host. Indeed, in the presence of the porphyrin trimer 5, the yield of the cyclization of a linear porphyrin hexamer, as a precursor of 1, could be improved from 8 to 30% (variable yield) to 50% (reproducible yield). Even the condensation of equimolecular amounts of porphyrin monomers 20b and 21b in the presence of 5 led-probably through a loose preorganized complex between the latter and the Zn(II) chelate 20b-to the formation of 1 in only five steps from 19, as compared with 13 steps of the synthesis via linear porphyrin hexamer in the absence of template. As evidenced by 1H NMR spectroscopic analysis of the supramolecular complex between 5 and an analogue of 1b in which all H-atoms at the pyrrole rings have been replaced by deuterium, in the presence of unlabeled 1b, a rapid dissociation and recombination of the host and guest molecules forming the supramolecular complex takes place even at low temperature (-40 C). As at 55 C all six Zn(II) porphyrinate rings of the complex 1b + 5 become magnetically equivalent in the 500 MHz 1H NMR time scale, approximate kinetic data for the ligand exchange process could be obtained.
The proportionality constant is the rate constant for the particular unimolecular reaction. the reaction rate is directly proportional to the concentration of the reactant. I hope my blog about 69861-71-8 is helpful to your research. Reference of 69861-71-8
Reference：
Chapter 1 An introduction to palladium catalysis,
Palladium/carbon catalyst regeneration and mechanical application method