870973-88-9Relevant academic research and scientific papers
Efficient chemoenzymatic dynamic kinetic resolution of 1-heteroaryl ethanols
Vallin, Karl S. A.,Posaric, David Wensbo,Hamersak, Zdenko,Svensson, Mats A.,Minidis, Alexander B. E.
experimental part, p. 9328 - 9336 (2010/03/24)
(Chemical Equation Presented) The scope and limitation of the combined ruthenium-lipase induced dynamic kinetic resolution (DKR) through O-acetylation of racemic heteroaromatic secondary alcohols, i.e., 1-heteroaryl substituted ethanols, was investigated. After initial screening of reaction conditions, Candida antarctica lipase B (Novozyme 435, N435) together with 4-chloro-phenylacetate as acetyl-donor for kinetic resolution (KR), in conjunction with the ruthenium-based Shvo catalyst for substrate racemization in toluene at 80°C, enabled DKR with high yields and stereoselectivity of various 1-heteroaryl ethanols, such as oxadiazoles, isoxazoles, 1H-pyrazole, or 1H-imidazole. In addition, DFT calculations based on a simplified catalyst complex model for the catalytic (de)hydrogenation step are in agreement with the previously reported outer sphere mechanism. These results support the further understanding of the mechanistic aspects behind the difference in reactivity of 1-heteroaryl substituted ethanols in comparison to reference substrates, as often referred to in the literature.
MGLUR5 MODULATORS
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Page/Page column 52, (2008/06/13)
The present invention is directed to compounds of formula (I) Wherein R1 to R5, X and Z are further defined in the description. The invention also relates to processes for the preparation of the compounds and to intermediates used in
