반응 #40283

반응 방정식

NaCl

Camphor sulfonic acid

p-anisaldehyde-dimethoxy-acetal

Pantothenic acid

→

3-{[2-(4-Methoxy-phenyl)-5,5-dimethyl-[1,3]dioxane-4-carbonyl]-amino}-propionic acid

수율 51.0%

용매

DCM

반응 조건

후처리

1. 1
   기타The crude reaction product
2. 2
   농축was concentrated
3. 3
   기타purified silica gel chromatography (6:1 hexane:EtOAC-EtOAc)
4. 4
   기타to yield a white solid (8A1) (3.8 g, 51% yield)

실험 절차

Pantothenic acid (7) (4.6 g, 2.24×10−2 mols) was dissolved in dry DCM (30 mL). Camphor sulfonic acid (0.52 g, 2.24×10−3 mols) and p-anisaldehyde-dimethoxy-acetal (3.82 mL, 2.24×10−2 mols) were added to the reaction mixture. The reaction was stirred overnight at room temperature with a drying tube. The crude reaction product was concentrated and purified silica gel chromatography (6:1 hexane:EtOAC-EtOAc) to yield a white solid (8A1) (3.8 g, 51% yield). mp=135-136° C. 1HNMR (400 MHz, DMSO) 0.93 (s, 3H), 0.99 (s, 3H), 2.38 (t, 2H, J=6.8 Hz), 3.25 (m, 1H), 3.34 (m, 1H), 3.5.9 (d, 1H, J=10.8 Hz), 3.62 (d, H, J=10.8 Hz), 3.74 (s, 3H), 4.07 (s, 1H), 5.50 (s, 1H), 6.91 (d, 2H, J=8.8 Hz), 7.41 (d, 2H, J=8.8 Hz). 13C-NMR (400 Mz, DMSO) 19.7, 22.2, 33.2, 34.4, 34.9, 55.8, 78.0, 83.8, 101.1, 114.0, 128.4, 131.1, 160.3, 168.9, 173.8. IR (NaCl, thin film), 3420, 2959, 1729, 1654, 1617, 1540, 1520, 1251, 1105 cm−1. MS (ESI) [M+Na]+360.1. HRMS (FAB) (m/z): [M+H]+ calcd for C17H23O6N, 338.1598, found 338.1594.

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