2-Amino-5-methylpyridine → (S)-4-methoxy-1-(5-methylpyridin-2-ylamino)-1-oxobutan-2-yl acetate

Participants

Reaction Conditions

Reaction Steps

5-Methylpyridin-2-amine (CAS no. 1603-41-4) (460 mg, 4.26 mmol) was added to (S)-2-acetoxy-4-methoxybutanoic acid (Intermediate F3) (500 mg, 2.84 mmol), in THF (8 mL) under nitrogen. The resulting suspension was stirred at 23° C. for 30 minutes. 4-(4,6-Dimethoxy[1.3.5]triazin-2-yl)-4-methylmorpholinium chloride hydrate (CAS no. 3945-69-5) (1.18 g, 4.26 mmol) was added and the suspension stirred for 40 hrs. The reaction mixture was concentrated and purified by flash silica chromatography, elution gradient 0 to 50% EtOAc in isohexane to afford (S)-4-methoxy-1-(5-methylpyridin-2-ylamino)-1-oxobutan-2-yl acetate (410 mg, 54%). 1H NMR (400 MHz, CDCl3) δ 2.13-2.28 (5H, m), 2.30 (3H, s), 3.31 (3H, s), 3.48-3.53 (2H, m), 5.37-5.40 (1H, m), 7.50-7.53 (1H, m), 8.09-8.11 (2H, m), 8.52 (1H, s); m/z (ESI+) (M+H)+=267; HPLC tR=1.22 min.

Provenance & Evidence