The remarkably high reactivity of α-cyano-α-fluorophenylacetyl chloride (CFPA–Cl) towards hindered nucleophiles in enantiomeric excess determination
作者:Yoshio Takeuchi、Noriaki Itoh、Toru Koizumi
DOI:10.1039/c39920001514
日期:——
The reaction of PhCF(CN)COCl 2b with 3,3-dimethylbutan-2-ol 5 was found to proceed more than 500 times faster than that of PhCCF3(OMe)COCl (MTPAâCl)1b, suggesting that the CFPA method should potentially lead to much less kinetic resolution than the currently much-used MTPA method in enantiometric excess determinations.
Chemistry of Novel Compounds with Multifunctional Carbon Structure. 8. Application of the α-Cyano-α-fluorophenylacetic Acid (CFPA) Method to the Enantiomeric Excess Determination of Some Hindered Alcohols in Asymmetric and Natural Product Syntheses
pinacolyl alcohol was found to proceed more than 500 times faster than that of MTPA chloride (1b) suggesting that the CFPA method induces potentially much less kinetic resolution than the widely used MTPA method in enantiomeric excess (ee) determination. Some applications of CFPA method were also investigated to evaluate practical use of CFPA reagent in ee determination of some hindered alcohols in asymmetric