136119-06-7Relevant academic research and scientific papers
Catalytic asymmetric transfer hydrogenation/dynamic kinetic resolution: an efficient synthesis of florfenicol
Wang, Xinlong,Xu, Lingjun,Yan, Lingjie,Wang, Haifeng,Han, Sheng,Wu, Yan,Chen, Fener
, p. 1787 - 1793 (2016)
A robust and practical method has been developed for the synthesis of florfenicol (1) starting from commercial available 4-(methylsulfonyl) benzoic acid. The key step in this synthesis was the Ru-chloramphenicol base catalyzed asymmetric transfer hydrogenation of N-Boc α-amino-β-ketoester 5 through a dynamic kinetic resolution, which afforded the key chiral building block, anti-(2S,3S)-α-Boc-amino-β-hydroxyl ester 4, with high diastereoselectivity (92% de) and enantioselectivity (78% ee). The synthesis of a series of novel chloramphenicol base ligands L1–L10 is also included. This protocol could also be used for the asymmetric synthesis of fully synthetic analogs of florfenicol.
SYNTHESIS AND CHIRAL-OPTICAL CHARACTERISTICS OF SCHIFF BASES FROM (+)-THREO-1-(4-NITROPHENYL)-2-AMINO-1,3-PROPANEDIOL
Potapov, V. M.,Dem'yanovich, V. M.,Zaitsev, V. P.,Sharipova, S. Kh.
, p. 2231 - 2235 (2007/10/02)
A series of Schiff bases were synthesized from (+)-threo-1-(4-nitrophenyl)-2-amino-1,3-propanediol with substituted benzaldehydes.The Schiff bases from benzaldehyde and para-substituted benzaldehydes give analogous circular dichroism spectra with negative Cotton effects in the regions of 350, 250, and 220 nm and a positive Cotton effect in the region of 270 nm.The positive Cotton effect is due to the interaction of the aromatic chromophores (4-NO2C6H4- and Ar-CH=N-), which form a right-handed spiral in one of the preferred conformations.
