Triphenylphosphine → 3-[4-(2-Pyridinylamino)butoxy]phenyl-3-methylbutanoic acid

To a solution of the product from Example 5, Step 3 (720 mg, 3.24 mmol) in DMF (9 mL) was added triphenylphosphine (850 mg, 3.24 mmol). The reaction solution was kept at ambient temperature for 1 hour and a solution of 2-(4-hydroxybutylamino)pyridine N-oxide (590 mg, 3.24 mmol) and diethyl azodicarboxylate (0.51 mL, 3.24 mmol) in DMF (5 mL) was added. The reaction solution was kept at room temperature for 18 hours and concentrated in vacuo. The residue was dissolved in ethyl acetate and washed with water. The aqueous solution was back extracted with ethyl acetate. The combined organic solution was washed with brine, dried (Na2SO4) and concentrated in vacuo. The residue was purified by chromatography (98:1:1 CH2Cl2:MeOH:NH4OH) to give the desired product, (560 mg, 45% yield).

1. waitThe reaction solution was kept at room temperature for 18 hours
2. concentrationconcentrated in vacuo
3. dissolutionThe residue was dissolved in ethyl acetate
4. washwashed with water
5. extractionThe aqueous solution was back extracted with ethyl acetate
6. washThe combined organic solution was washed with brine
7. dry with materialdried (Na2SO4)
8. concentrationconcentrated in vacuo
9. customThe residue was purified by chromatography (98:1:1 CH2Cl2:MeOH:NH4OH)

ORD record

ord-079ac4cdb2aa49b08a17a38bc4e72864

Source dataset

uspto-grants-2004_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06720315B2