(S)-2-[(R)-Fluoro(phenyl)methyl]oxirane:  A General Reagent for Determining the ee of α-Chiral Amines

Abstract

(S)-2-[(R)-Fluoro(phenyl)methyl]oxirane is a new, synthetic, yet enantiopure, chiral resolution reagent, readily obtained from enantiopure (2S,3S)-phenylglycidol, that reacts with a variety of alpha-chiral primary and secondary amines in a straightforward manner through a regioselective ring-opening. Diastereomeric products are easily identified and quantified by (19)F, (1)H, and (13)C NMR and by HPLC, which makes this fluorinated compound a most versatile reagent for the analysis of scalemic mixtures of amines. [reaction: see text]

Unprecedented Asymmetric Epoxidation of Isolated Carbon–Carbon Double Bonds by a Chiral Fluorous Fe(III) Salen Complex: Exploiting Fluorophilic Effect for Catalyst Design

“…100 %, 55 % ee [The ee was determined by HPLC analysis (DAICEL CHIRAL-CEL OD-3 column; hexane, flow rate 0.5 mL min, t R = 26.95 min (major), t R = 31.65 min (minor)]; 1 H NMR (270 MHz, CDCl 3 ) δ 1.44-1.68 (m, 4 H), 1.94 (s, 2 H), 2.09 (s, 1 H), 2.29 (s, 1 H), 3.08 (s, 1 H), 7.31-7.39 (m, 5 H). [28] Conv. 100 %, 60 % ee [The ee was determined by HPLC analysis (DAICEL CHIRALCEL OD-3 column; hexane/iPrOH = 99:1, flow rate 0.4 mL min, t R = 14.01 min (major), t R = 21.02 min (minor)]; 1 H NMR (270 MHz, CDCl 3 ) δ 3.73 (s, 3 H), 4.26 (s, 1 H), 6.68 (d, J = 8.64 Hz, 2 H), 6.93 (d, J = 8.64 Hz, 2 H), 7.…”

Synthesis of New Trifluoromethylated Hydroxyethylamine‐Based Scaffolds

“…In most of these cases, yields and the diversity of amino acids used were poor. [32][33][34][35][36][37][38][39][40][41][42][43][44][45] Currently, there are only two efficient methods for this reaction. The first one involves the use of Ca(OTf) 2 as a promoter of the reaction.…”

Cage-like amino alcohols. synthesis, reactions, and application

“…The main relations holding in opening of oxirane ring, as well as in aminolysis of epoxy derivatives, were revealed by studying the kinetics, regio-and stereoselectivity, and conformational features of these reactions; 1 H, 13 C, and 19 F NMR spectroscopy was used to determine the structure of epoxide aminolysis products [22]. The generally accepted mechanism of epoxide ring opening was proposed in 1959 [23] and was then confirmed by other studies [24,25].…”