Vinyl Acetate → (1R)-1-[2-(3-chlorophenyl)-2H-tetrazol-5-yl]ethyl acetate

関与物質

反応条件

反応手順

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).

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