Réaction #40600

Équation de réaction

salvinorin B

(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

triphenylphosphine

bromoform

triphenylphosphine

bromoform

→

36

Rendement 59.0%

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

Rendement 59.0%

Solvants

CH2Cl2

Conditions de réaction

Traitement

1. 1
   workup.WAITwas still present after 16 h
2. 2
   workup.STIRRINGthe mixture was stirred for an additional 3 h
3. 3
   AutreThe solvent was removed under reduced pressure
4. 4
   Autreaffording a crude solid
5. 5
   AutreThe oil was purified by column chromatography (eluent: 30% EtOAc/n-hexanes)

Mode opératoire

A mixture of salvinorin B (8a) (0.15 g, 0.38 mmol), triphenylphosphine (0.21 g, 0.80 mmol), and bromoform (0.15 g, 0.45 mmol) in CH2Cl2 (30 mL) was stirred at room temperature overnight. TLC indicated that starting material was still present after 16 h, thus additional triphenylphosphine (0.11 g, 0.42 mmol) and bromoform (0.07 g, 0.21 mmol) were added and the mixture was stirred for an additional 3 h. The solvent was removed under reduced pressure affording a crude solid. The oil was purified by column chromatography (eluent: 30% EtOAc/n-hexanes) to afford 0.10 g (59%) of 36 as a white solid, mp 170-173° C. (EtOAc/n-hexanes); 1H NMR (CDCl3): δ 1.15 (3H, s); 1.48 (3H, s); 1.60 (3H, m); 1.81 (1H, dd, J=2.7, 9.9); 1.95 (1H, dd, J=13.2, 26.1); 2.1 (2H, m); 2.27 (1H, s); 2.47 (1H, dd, J=4.8, 13.2); 2.66 (1H, m); 2.80 (1H, dd, J=3.3, 13.2); 3.70 (3H, s); 3.89 (2H, d, J=2.4); 4.45 (1H, m); 5.55 (1H, dd, J=4.8, 11.7); 6.38 (1H, dd, J=0.9, 1.5); 7.4 (2H, m).

Source