135311-75-0Relevant academic research and scientific papers
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
Takeuchi,Itoh,Kawahara,Koizumi
, p. 1861 - 1870 (2007/10/02)
The reaction of CFPA chloride (2b) with 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
Chemistry of Novel Compounds with Multifunctional Carbon Structure. 9. Molecular Design, Synthetic Studies, and NMR Investigation of Several Efficient Chiral Derivatizing Reagents which Give Very Large (19)F NMR Δδ Values in Enantiomeric Excess Determination
Takeuchi, Yoshio,Itoh, Noriaki,Satoh, Toshihiro,Koizumi, Toru,Yamaguchi, Kentaro
, p. 1812 - 1820 (2007/10/02)
In order to develop efficient ee-determining reagents potentially superior to MTPA (1), some multifunctional compounds 2-5 were rationally designed.From NMR investigations of the analogous diastereomeric derivatives it was found that the chemical shift differences for each pair of diastereomers (Δδ values) for CFPA derivatives 5d-f were approximately five times greater in (19)F NMR spectra and two times greater in 1H NMR spectra than those of 1d-f.Synthesis of the optically pure CFPA, (-)-5a nd (+)-5a, was achieved by nitrosation of each diasteromer of the optically active N-(1-phenylethyl)amides, 5fM and 5fL, followed by thermal decomposition.Various derivatives were prepared by the condensation of 5b and 1b with alcohol and amine nucleophiles, and both ΔδF and ΔδH values were obtained for each compound.The CFPA derivatives 5d-m have proven to be significantly superior for ee determinations when compared to the corresponding MTPA derivatives 1d-m, particularly in compounds having remotely disposed chiral centers.
The Remarkably High Reactivity of α-Cyano-α-fluorophenylacetyl Chloride (CFPA-Cl) towards Hindered Nucleophiles in Enantiomeric Excess Determination
Takeuchi, Yoshio,Itoh, Noriaki,Koizumi, Toru
, p. 1514 - 1515 (2007/10/02)
The reaction of PhCF(CN)COCl 2b with 3,3-dimethylbutal-2-ol 5 was found to proceed more than 500 times faster than that of PhCCF3(OMe)COCl (MTPA-Cl) 1b, suggesting that the CFPA method should potentially lead to much less kinetic resolution than the curre
