98995-33-6Relevant academic research and scientific papers
Origins of initiation rate differences in ruthenium olefin metathesis catalysts containing chelating benzylidenes
Engle, Keary M.,Lu, Gang,Luo, Shao-Xiong,Henling, Lawrence M.,Takase, Michael K.,Liu, Peng,Houk,Grubbs, Robert H.
, p. 5782 - 5792 (2015)
A series of second-generation ruthenium olefin metathesis catalysts was investigated using a combination of reaction kinetics, X-ray crystallography, NMR spectroscopy, and DFT calculations in order to determine the relationship between the structure of the chelating o-alkoxybenzylidene and the observed initiation rate. Included in this series were previously reported catalysts containing a variety of benzylidene modifications as well as four new catalysts containing cyclopropoxy, neopentyloxy, 1-adamantyloxy, and 2-adamantyloxy groups. The initiation rates of this series of catalysts were determined using a UV/vis assay. All four new catalysts were observed to be faster-initiating than the corresponding isopropoxy control, and the 2-adamantyloxy catalyst was found to be among the fastest-initiating Hoveyda-type catalysts reported to date. Analysis of the X-ray crystal structures and computed energy-minimized structures of these catalysts revealed no correlation between the Ru-O bond length and Ru-O bond strength. On the other hand, the initiation rate was found to correlate strongly with the computed Ru-O bond strength. This latter finding enables both the rationalization and prediction of catalyst initiation through the calculation of a single thermodynamic parameter in which no assumptions about the mechanism of the initiation step are made.
2-OXO-3,4-DIHYDROPYRIDINE-5-CARBOXYLATES AND THEIR USE
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Page/Page column 174, (2016/04/20)
The present invention is directed to novel compounds of Formula (I), pharmaceutically acceptable salts or solvates thereof, and their use.
