Lithium diisopropylamide → (2S)-2-(N-(2-Azido-benzoyl)-N-formylamino)-propionic acid tert-butyl ester

A stirred solution of (2S)-2-formylamino-propionic acid tert-butyl ester (3.524 g, 20.3 mmol) in anhydrous THF (50 mL) was treated at −78° C. with LDA (20.3 mmol) and the reaction was stirred for 15 min. A solution of 2-azidobenzoyl chloride (T. Okawa, T. Sugimori, S. Eguchi and A. Kakehi, Heterocycles, 1998, 47, 1, 375-382) (20.6 mmol) in anhydrous THF (20 mL) was then added dropwise and the reaction mixture was stirred at −78° C. for 1 h before being quenched with saturated aq. NH4Cl. The reaction was allowed to warm to room temperature and the organic layer was washed with saturated aq. NH4Cl, dried (MgSO4), filtered and evaporated and residue was purified by flash chromatography (20% ethyl acetate in hexane) to afford the sub-title compound as a pale yellow oil (3.437 g, 53%): 1H NMR (400 MHz CDCl3) δ 1.49 (9H, s), 1.60 (3H, d), 5.18 (1H, m), 7.27 (2H, m), 7.40 (1H, d), 7.59 (1H, t), 8.60 (1H, s).

1. stirringthe reaction mixture was stirred at −78° C. for 1 h
2. custombefore being quenched with saturated aq. NH4Cl
3. washthe organic layer was washed with saturated aq. NH4Cl
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. customevaporated
7. customresidue was purified by flash chromatography (20% ethyl acetate in hexane)

ORD record

ord-85117f94fa5c49a0aea414b6c41a10d3

Source dataset

uspto-grants-2011_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07906650B2