Reacción #40595

Ecuación de reacción

8a

(2S,4aS,6aR,7R,9S,10aS,10bR)-9-(hydroxy)-2-(3-furanyl)dodecahydro-6a,10b-dimethyl-4,10-dioxo-2H-naphtho[2,1-c]pyran-7-carboxylic acid methyl ester

NEt3

chlorotrimethylsilane

→

16

Rendimiento 68.0%

(2S,4aR,6aR,7R,9S,10aS,10bR)-9-(trimethylsilanyloxy)-2-(3-furanyl)-dodecahydro-6a,10b-dimethyl-4,10-dioxo-2H-naphtho[2,1-c]pyran-7-carboxylic acid methyl ester

Rendimiento 68.0%

Disolventes

CH2Cl2

Condiciones de reacción

Tratamiento posterior

1. 1
   LavadoThe mixture was washed with saturated NaHCO3 (2×10 mL) and H20 (50 mL)
2. 2
   Secadodried (Na2SO4)
3. 3
   Otrothe solvent was removed under reduced pressure
4. 4
   OtroThe resulting crude solid was purified by column chromatography (eluent: ethyl acetate/nhexanes)

Procedimiento

A solution of 8a (0.08 g, 0.20 mmol), NEt3 (0.1 mL, 0.72 mmol) and chlorotrimethylsilane (0.1 mL, 0.79 mmol) in CH2Cl2 (30 mL) was stirred at room temperature overnight. The mixture was washed with saturated NaHCO3 (2×10 mL) and H20 (50 mL), dried (Na2SO4), and the solvent was removed under reduced pressure. The resulting crude solid was purified by column chromatography (eluent: ethyl acetate/nhexanes) to afford 16 (0.06 g, 68%) as a white solid, mp 197-200° C.; 1H NMR (CDCl3): δ 0.14 (9H, s, (CH3)3SiO; 1.11 (3H, s, H-19); 1.48 (3H, s, H-29); 1.50-1.73 (3H, m, H-7α,β and H-11β); 1.79 (1H, ddd, J=3.0, 3.0, 10.5 Hz, H-6α); 2.03 (1H, dd, obscured, H-8); 2.06 (1H, s, H-10); 2.10-2.38 (3H, m, H-3α,β and H-6β); 2.57 (1H, dd, J=5.1, 10.5 Hz, H-11α); 2.69 (1H, dd, J=3.9, 12.9 Hz, H-4); 3.72 (3H, s, CO2CH3); 4.12 (1H, dd, J=7.5, 11.7 Hz, H-2); 5.56 (1H, dd, J=5.1, 11.4 Hz, H-12); 6.38 (1H, dd, J=0.8, 1.7 Hz, H-14); 7.40 (1H, m, H-15); 7.42 (1H, m, H-16).

Fuente