Реакция #172731

Уравнение реакции

4-methoxycarbonylphenylboronic acid

(1R,3aS,5aR,5bR,7aR,11aR,11bR,13bR)-benzyl 5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-9-(trifluoromethylsulfonyloxy)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysene-3a-carboxylate

2-propanol

sodium carbonate monohydrate

→

title compound

Выход 68.4%

(1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-benzyl 9-(4-(methoxycarbonyl)phenyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysene-3a-carboxylate

Выход 68.4%

Растворители

dioxane

water

Условия реакции

Обработка

1. 1
   ДругоеThe flask was attached to a reflux condenser
2. 2
   Другоеflushed with N2
3. 3
   Температураheated
4. 4
   Температураto reflux overnight
5. 5
   workup.ADDITIONdiluted with water (75 mL)
6. 6
   ЭкстракцияThe mixture was extracted with ethyl acetate (3×75 mL)
7. 7
   Промывкаwashed with brine (75 mL)
8. 8
   СушкаThe combined organic layers were dried with MgSO4
9. 9
   Фильтрацияfiltered
10. 10
    Концентрированиеconcentrated under reduced pressure
11. 11
    Другоеpurified by silica gel flash chromatography
12. 12
    workup.ADDITIONThe fractions containing the expected product
13. 13
    Концентрированиеconcentrated under reduced pressure

Методика

To a solution of (1R,3aS,5aR,5bR,7aR,11aR,11bR,13bR)-benzyl 5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-9-(trifluoromethylsulfonyloxy)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysene-3a-carboxylate (6.21 g, 9.18 mmol) in dioxane (25 mL) was added 2-propanol (25 mL) and water (15 mL) followed by sodium carbonate monohydrate (3.42 g, 27.5 mmol), 4-methoxycarbonylphenylboronic acid (2.478 g, 13.77 mmol), and tetrakis(triphenylphosphine)palladium(0) (0.318 g, 0.275 mmol). The flask was attached to a reflux condenser, flushed with N2 and heated to reflux overnight. The mixture was then cooled to rt and diluted with water (75 mL). The mixture was extracted with ethyl acetate (3×75 mL) and washed with brine (75 mL). The combined organic layers were dried with MgSO4, filtered, and concentrated under reduced pressure. The residue was adsorbed to silica gel and purified by silica gel flash chromatography using a 0-20% ethyl acetate in hexanes gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to give the title compound (4.16 g, 6.28 mmol, 68.4% yield) as a white foam. 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 7.92 (d, J=8.24 Hz, 2H), 7.40-7.29 (m, 5H), 7.19 (d, J=8.24 Hz, 2H), 5.28 (dd, J=6.10, 1.83 Hz, 1H), 5.19-5.07 (m, 2H), 4.73 (d, J=1.83 Hz, 1H), 4.60 (s, 1H), 3.90 (s, 3H), 3.04 (td, J=10.91, 4.73 Hz, 1H), 2.20-2.32 (m, 2H), 2.09 (dd, J=17.24, 6.26 Hz, 1H), 1.95-1.82 (m, 2H), 1.69 (s, 3H), 0.97 (s, 3H), 0.95 (s, 3H), 0.92 (s, 3H), 0.91 (s, 3H), 1.75-0.87 (m, 17H), 0.82 (s, 3H).

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