Hydrochloric Acid → 3-Acetoxy-5-biphenyl-4-yl-pentanoic acid tert-butyl ester

Acetic anhydride (40 μL, 0.42 mmol) was added to a stirred solution of 5-biphenyl-4-yl-3-hydroxy-pentanoic acid tert-butyl ester (Intermediate 3, 54 mg, 0.17 mmol), 4-dimethylaminopyridine (5.0 mg, 41 μmol) and pyridine (54 μL, 0.66 mol) in dichloromethane (1 mL) at room temperature under nitrogen. Stirring was continued for 12 hours at room temperature before the addition of 2 M hydrochloric acid (5 mL) and dichloromethane (5 mL). The phases were separated and aqueous phase extracted with dichloromethane (3×5 mL). The organic phases were combined, washed with brine (5 mL) and dried (MgSO4). The solvent was removed by evaporation under reduced pressure to give the title compound (45 mg, 74%) as a colourless gum. LC/MS: 3.91 min; z/e 386, calcd (M+NH4) 386. 1H NMR (400 MHz: CDCl3): 7.59 (2 H), 7.52 (2 H), 7.42 (2 H), 7.33 (1 H), 7.25 (2 H), 5.29 (1 H), 2.70 (2 H), 2.53 (2 H), 2.05 (3 H), 1.97 (2H), 1.42 (9 H).

1. customThe phases were separated
2. extractionaqueous phase extracted with dichloromethane (3×5 mL)
3. washwashed with brine (5 mL)
4. dry with materialdried (MgSO4)
5. customThe solvent was removed by evaporation under reduced pressure

ORD record

ord-62d54a42bcec4fe7a53ed57b89d42e65

Source dataset

uspto-grants-2007_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07250439B2