32860-39-2Relevant academic research and scientific papers
Highly selective hydrolytic kinetic resolution of terminal epoxides catalyzed by chiral (salen)CoIII complexes. Practical synthesis of enantioenriched terminal epoxides and 1,2-diols
Schaus, Scott E.,Brandes, Bridget D.,Larrow, Jay F.,Tokunaga, Makoto,Hansen, Karl B.,Gould, Alexandra E.,Furrow, Michael E.,Jacobsen, Eric N.
, p. 1307 - 1315 (2007/10/03)
The hydrolytic kinetic resolution (HKR) of terminal epoxides catalyzed by chiral (salen)CoIII complex 1·OAc affords both recovered unreacted epoxide and 1,2-diol product in highly enantioenriched form. As such, the HKR provides general access to useful, highly enantioenriched chiral building blocks that are otherwise difficult to access, from inexpensive racemic materials. The reaction has several appealing features from a practical standpoint, including the use of H2O as a reactant and low loadings (0.2-2.0 mol %) of a recyclable, commercially available catalyst. In addition, the HKR displays extraordinary scope, as a wide assortment of sterically and electronically varied epoxides can be resolved to ≥ 99% ee. The corresponding 1,2-diols were produced in good-to-high enantiomeric excess using 0.45 equiv of H2O. Useful and general protocols are provided for the isolation of highly enantioenriched epoxides and diols, as well as for catalyst recovery and recycling. Selectivity factors (krel) were determined for the HKR reactions by measuring the product ee at ca. 20% conversion. In nearly all cases, krel values for the HKR exceed 50, and in several cases are well in excess of 200.
Kinetic chiral resolutions of 1,2-diols and desymmetrization of glycerol catalyzed by glycerol kinase
Keith Chenault,Chafin, Laura F.,Liehr, Sebastian
, p. 4039 - 4045 (2007/10/03)
Enantioselective phosphorylation catalyzed by glycerol kinase (EC 2.7.1.30) facilitated the kinetic chiral resolution of 3-chloro-1,2- propanediol, 3-fluoro-1,2-propanediol, 3-butene-1,2-diol, and 1,2,4- butanetriol. Both enantiomers of each compound were isolated is free diol or triol form, in excellent enantiomeric purity (91 to > 99.5% ee) and in moderate to good yield (60-94% of theoretical). The enantioselectivities of glycerol kinase from different sources were compared using 1,2,4-butanetriol as the substrate. The effect of elevated temperatures on enzymatic activity, stability, and enantioselectivity were studied, and procedures for the isolation of diol and triol products were optimized. Glycerol kinase- catalyzed phosphorylation facilitated the three-step chemoenzymatic conversion of glycerol to (S)-1,2-O-isopropylideneglycerol in 83% yield and > 99.5% ee).
