Vinyl Acetate → (S)-3-hydroxy-3-(2-thienyl) propanenitrile

Beteiligte Stoffe

Reaktionsschritte

Enzymatic Transesterification of 3-hydroxy-3-(2-thienyl) propanenitrile (1): To a solution of 3-hydroxy-3-(2-thienyl) propanenitrile (1) (5 mmol) dissolved in diisopropyl ether (100 mL), Pseudomonas cepacia lipase immobilized on diatomite (PS-D) (500 mg) and vinyl acetate (25 mmol) were added successively and incubated at 25° C. in an orbital shaker. After 50% completion of the reaction (14 h) as indicated by HPLC, the reaction mixture was filtered and solvent was evaporated under reduced pressure. The residue was subjected to column chromatography to separate the acetate formed and the unreacted alcohol. The optical purity of these compounds were determined by HPLC. (S)-3-hydroxy-3-(2-thienyl) propanenitrile (S-1) 42% yield, ee>99%; [α]30D=−33.5 (c 1, CHCl3); IR (Neat) 3475, 3075, 2878, 2251, 1105, 698 cm−1; 1H NMR (200 MHz, CDCl3) δ 2.82 (dd, 2H, J=3.0 Hz, J=6.6 Hz), 3.0 (s, 1H) 5.25 (t, 1H, J=5.5 Hz), 6.98 (t, 1H, J=4.9 Hz), 7.05 (d, 1H, J=3.7 Hz), 7.28 (d, 1H, J=4.9 Hz); 13C NMR (75 MHz) δ 28.1, 66.0, 117.0, 124.6, 125.6, 127.0, 144.4; Mass (EI) 153 127, 113, 85.

Herkunft & Nachweise