反应详情

(S)-3-[5-(1-t-butoxycarbonylamino-2-biphenyl-4-yl-ethyl)-tetrazol-1-yl]-propionitrile (9.22 g, 22 mmol) is dissolved in methylene chloride (135 mL) under nitrogen. To the stirred solution is added trifluoroacetic acid (50 mL). After 50 minutes, the solution is concentrated under reduced pressure and the residue is treated with ether (200 mL). The amorphous solid is filtered off, washed with ether and dried under vacuum at 45° for 2 hours, then at room temperature for 18 hours to yield (S)-3-[5-(1-amino-2-biphenyl-4-yl-ethyl)-tetrazol-1-yl]-propionitrile trifluoroacetate salt, m.p. 211°-212°, [α]D =+23.35° (c 1.05, DMSO).

1. concentrationthe solution is concentrated under reduced pressure
2. additionthe residue is treated with ether (200 mL)
3. filtrationThe amorphous solid is filtered off
4. washwashed with ether
5. customdried under vacuum at 45° for 2 hours