Convenient enzymatic resolution of (R,S)‐2‐methylbutyric acid catalyzed by immobilized lipases

Abstract

The application of several immobilized lipases has been explored in the enantioselective esterification of (R,S)-2-methylbutyric acid, an insect pheromone precursor. With the use of Candida antarctica B, using hexane as solvent, (R)-pentyl 2-methylbutyrate was prepared in 2 h with c 40%, ee p 90%, and E = 35, while Thermomyces lanuginosus leads to c 18%, ee p 91%, and E = 26.The (S)-enantiomer was obtained by the use of Candida rugosa or Rhizopus oryzae (2-h reaction, c 34% and 35%, ee p 75 and 49%, and E = 10 and 4, respectively). Under optimal conditions, the effect of the solvent, the molar ratio, and the nucleophile were evaluated.

Mass spectrometric analysis and biostimulatory effects of boar seminal gel, saliva and semen in pigs

“…In Pityogenes chalcographus , nonane is a component of the male aggregation pheromone. 2-methylbutyric acid is an insect pheromone precursor (Mittersteiner et al, 2017). It is a sex attractant pheromone blend of female house mice (Varner et al, 2018).…”

Synthetic Versatility of β-Alkoxyvinyl Trichloromethyl Ketones for Obtaining [1,2,4]Triazolo[1,5-a]pyrimidines

“…It is well known that the size of the substituents play an important role in regio-or enantioselective reactions and, since R 1 and R 2 = H, there is no difference in the group size for recognition during the reaction. 20 Thus, for entries 1 and 6 ( Table 2), mixtures of 6 and 10%, respectively, of the 5-(trichloromethyl)-substituted regioisomers were obtained. For all the other examples, only the 7-(trichloromethyl)-substituted regioisomer was obtained.…”