Tetrabutylammonium Fluoride → tert-butyl (2S,5R)-2-[(2-{[N-(tert-butoxycarbonyl)-4-fluoro-beta-(4-fluorophenyl)-L-phenylalanyl]amino}-6-fluorophenoxy)methyl]-5-(hydroxymethyl)morpholine-4-carboxylate

Participants

Reaction Steps

1M TBAF (1766 μl, 1.766 mmol) in THF was added to a solution of tert-butyl (2S,5S)-2-[(2-{[N-(tert-butoxycarbonyl)-4-fluoro-β-(4-fluorophenyl)-L-phenylalanyl]amino}-6-fluorophenoxy)methyl]-5-({[tert-butyl(dimethyl)silyl]oxy}methyl)morpholine-4-carboxylate (977 mg, 1.177 mmol) in THF (5.89 mL) at room temperature and the reaction stirred at room temperature until completion (6 hours). The reaction was quenched with a saturated aqueous solution of KH2PO4 and the mixture was extracted with ethyl acetate (3×50 mL). The combined organic fractions were dried over MgSO4, filtered and the solvent was evaporated under reduced pressure. The crude material was then purified on silica gel (120 g), eluting with a gradient of 0-100% a 7:2:1 CHCl3/EtOAc/MeOH blend in CHCl3 to afford the title compound (439 mg, 0.589 mmol, 50% yield) as a white foam, MS (ESI): m/z=616.4 (M+H-boc); 96% pure by LC/MS.

Provenance & Evidence