Tributylphosphine → 2-({5-[3-(2-Pyridylamino)propoxy]indolyl}methyl)pentanoic acid

1,1′-(Azodicarbonyl)dipiperidine (0.12 g, 0.48 mmol) was added to the solution of methyl 2-[(5-hydroxyindolyl)methyl]pentanoate (0.03 g, 0.12 mmol), as prepared in the preceding step, 2-(3-hydroxypropyl)aminopyridine (0.026 g, 0.17 mmol), as prepared in step b of Example 1, and tri-n-butylphosphine (0.09 g, 0.46 mmol) in tetrahydrofuran (6.0 mL). After stirring at ambient temperature overnight (16 h), the reaction was concentrated and the residue was purified by flash chromatography on silica gel (10%-50% ethyl acetate in hexane) to give the title compound as a yellow oil (0.016 g, 36%). 1H-NMR (400 MHz, CDCl3) δ 8.08 (m, 1H), 7.20 (d, J=8.9 Hz, 1H), 7.07 (d, J=2.4 Hz, 1H), 7.02 (d, J=3.3 Hz, 1H), 6.88 (dd, J=8.9, 2.4 Hz, 1H), 6.53 (m, 1H), 6.40 (m, 2H), 4.32 (br s, 1H), 4.42 (m, 1H), 4.25 (m, 3H), 3.52 (m, 5H), 2.91 (m, 1H), 2.20 (m, 2H), 1.72 (m, 2H), 1.43 (m, 3H), 0.95 (t, J=7.2 Hz, 3H).

1. concentrationthe reaction was concentrated
2. customthe residue was purified by flash chromatography on silica gel (10%-50% ethyl acetate in hexane)

ORD record

ord-d67725fceb454be4b002d26cbae14998

Source dataset

uspto-grants-2005_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06855722B2