反应详情

温度

30 °C

2.22 g (9.93 mmol) racemic 1-[2-(3-chlorophenyl)-2H-tetrazol-5-yl]ethanol and 0.40 g Novozyme 435® are taken up under Ar in toluene (120 mL). After addition of 109 μL (1.18 mmol) vinyl acetate the reaction was run at r.t. o.n., followed by addition of 0.12 g Novozyme 435® and 218 μL (2.36 mmol) vinylacetate and increasing the temperature to 30° C. o.n. Further addition of 2 g Novozyme 435® and 150 μL (1.63 mmol) vinylacetate gave after 7 h ca 41% conversion of starting material. To enhance yield, the reaction was filtered over celite washed with DCM, evaporated to dryness, then taken up in toluene (250 mL). After addition of 0.3 g Novozyme 435® and 200 μL (2.17 mmol) vinylacetate under Ar, 48% conversion after 4 h at r.t. were achieved. Filtration over celite and washing with DCM gave crude which was purified over silica using DCM neat, followed by EA/Hep=1/2, yielding 1.26 g (48%) of the title compound. 1H NMR: 8.15 (m, 1H), 8.03 (m, 1H), 7.48 (m, 2H), 6.27 (q, 1H), 2.14 (s, 3H), 1.77 (d, 3H).

1. customwas run at r.t.
2. customgave after 7 h ca 41% conversion of starting material
3. customTo enhance yield
4. filtrationthe reaction was filtered
5. washover celite washed with DCM
6. customevaporated to dryness
7. filtrationFiltration over celite
8. washwashing with DCM
9. customgave crude which
10. customwas purified over silica