Trifluoroacetic acid → HCID 58706342, Verbindung
Reaktionsgleichung
C(OC([N:8]1[CH2:13][CH2:12][CH:11]([NH:14][C:15]2[O:16][C:17]3[CH:23]=[CH:22][C:21]([C:24]#[N:25])=[CH:20][C:18]=3[N:19]=2)[CH2:10][CH2:9]1)=O)(C)(C)C.FC(F)(F)C(O)=O>ClCCl>[NH:8]1[CH2:9][CH2:10][CH:11]([NH:14][C:15]2[O:16][C:17]3[CH:23]=[CH:22][C:21]([C:24]#[N:25])=[CH:20][C:18]=3[N:19]=2)[CH2:12][CH2:13]1Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
To a solution of 4-(5-cyano-benzooxazol-2-ylamino)-piperidine-1-carboxylic acid tert-butyl ester (6.62 g, 19.33 mmol, 1.0 equiv) in dichloromethane (100 mL) was added trifluoro-acetic acid (7.4 mL, 11.03 g, 96.7 mmol, 5.0 equiv). After stirring under Ar at rt for 18 h excess trifluoro-acetic acid was removed under reduced pressure and the crude solid taken up in dichloromethane (100 mL) and water (100 mL). The pH was adjusted to 10 by addition of a conc. solution of K2CO3 and the solution extracted with dichloromethane/2-propanol (4:1, 3×50 mL). The combined organic phases were dried over MgSO4, the organic solvent evaporated under reduced pressure and the crude reaction product purified with column chromatography on silica eluting with a gradient of dichloromethane/methanol (100:0→95:5) containing 33% of NH4OH to yield 4.36 g (93%) of the title compound. MS (ESI): 243.1 [M+H]+.