HCID 69734264, compound → HCID 86589157, compound

Participants

Reaction Steps

Methyl(2S)-2-({3-[(dipropylamino)carbonyl]benzoyl}amino)-4-methylpentanoate (1.65 g, 4.4 mmol) in 20 mL of toluene under nitrogen is cooled to −78° C. To this is added, dropwise over 5 min, 11 mL of a 1 M solution of Dibal in toluene. The mixture is stirred an additional 6 minutes, and is then quenched by addition of 2 mL of methanol. The cold bath is removed and 20 mL of a Rochelle salt solution is added and vigorously stirred while the mixture warms to ambient temperature. The product is extracted into ether and the organic phase is washed successively with Rochelle salt solution, water, and brine. It is dried over Na2SO4, concentrated, and chromatographed over silica gel, eluting with 50% ethyl acetate in heptane, to afford the title compound as a colorless oil (0.79 g, 2.3 mmol, 52%). 1H NMR (CDCl3) δ 9.7 (s, 1H), 7.85 (m, 1H), 7.79 (s, 1H), 7.49 (m, 2H), 6.81 (d, J=7 Hz, 1H), 4.78 (m, 1H), 3.46 (br t, 2H), 3.15 (br t, 2H), 1.82 (m, 2H), 1.70 (m, 2H), 1.62-1.53 (m, 3H), 1.01 (m, 9H), 0.75 (br t, 3H).

Provenance & Evidence