1426155-77-2

Upstream product

• 1426155-80-7 methyl (RS)-2-phenyl-2-[1,1-bis(trifluoromethyl)-2,2,2-trifluoroethoxy]acetate 
• 21210-43-5 (S)-Methyl mandelate 
• 60633-83-2 methyl (2S)‐2‐[(methylsulfonyl)oxy]‐2‐phenylacetate 

Relevant academic research and scientific papers

Chiral Recognition Studies of α-(Nonafluoro- tert -butoxy)carboxylic Acids by NMR Spectroscopy

Three chiral α-(nonafluoro-tert-butoxy)carboxylic acids (R)-1, (RS)-2, (R)-3 were synthesized to examine their application as chiral solvating agents with amines. As a model compound, first (S)- and/or (RS)-α-phenylethylamine was used, and their diastereomeric salts were investigated by 1H and 19F NMR and ECD spectroscopy. The NMR spectroscopic studies were carried out at room temperature using the slightly polar CDCl3 and apolar C6D6 as solvents in 5 mM and 54 mM concentrations. The difference of the chemical shifts (Δδ) in the diastereomeric complexes is comparable with other, well-known chiral derivatizing and solvating agents (e.g., Mosher's acid, Pirkle's alcohol). Diastereomeric salts of racemic acids (RS)-1 and (RS)-2 with biologically active amines (1R,2S)-ephedrine and (S)-dapoxetine were also investigated by 19F NMR spectroscopy.

Synthesis of optically active α-(nonafluoro-tert-butoxy)carboxylic acids

Three novel α-(nonafluoro-tert-butoxy)carboxylic esters were synthesized by two methods: the Mitsunobu reaction of optically active (S)-α-hydroxycarboxylic esters and the Williamson synthesis starting from the corresponding O-mesyl derivatives. Both procedures from ethyl (S)-lactate resulted in the formation of a fluorous optically active (R)-lactic acid ester derivative, while the reactions from methyl (S)-mandelate took place with racemization. The proposed mechanism of this racemization is described. The conversion of methyl (S)-phenyllactate under Mitsunobu conditions was also stereospecific, but the reaction of its O-mesyl derivative yielded a mixture of substitution and elimination products. The optical purity of the α-(nonafluoro-tert-butoxy)carboxylic acids prepared by the hydrolysis of the above esters was determined by 1H NMR spectroscopy.