Reaktion #172734

Reaktionsgleichung

diphenyl phosphoryl azide

(1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-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-carboxylic acid

triethylamine

→

title compound

Ausbeute 86.4%

methyl 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-isocyanato-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]chrysen-9-yl)benzoate

Ausbeute 86.4%

Lösungsmittel

EtOAc

1,4-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto cool to rt
2. 2
   Waschenwashed with 1N NaOH (2×70 mL)
3. 3
   ExtraktionThe combined aqueous layer was extracted with EtOAc (2×150 mL)
4. 4
   TrocknenThe combined organic layer was dried over Na2SO4
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated to a slurry (75 mL) which
7. 7
   Sonstigewas stored in a refrigerator overnight
8. 8
   FiltrationThe slurry was filtered
9. 9
   Waschenthe white solid product was washed with Et2O
10. 10
    EinengenThe liquid filtrate was concentrated to a yellow slurry which
11. 11
    Filtrationwas filtered
12. 12
    Waschenwashed with Et2O
13. 13
    Sonstigeto give more white solid product
14. 14
    Sonstigedried in vacuo

Vorschrift

To a slurry of (1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-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-carboxylic acid (10 g, 17.46 mmol) in 1,4-dioxane (200 mL) was added triethylamine (4.38 mL, 31.4 mmol) followed by diphenyl phosphoryl azide (5.82 mL, 26.2 mmol). The resulting white slurry was heated to 100° C. After 5 h, the reaction was allowed to cool to rt and was then diluted with EtOAc and washed with 1N NaOH (2×70 mL). The combined aqueous layer was extracted with EtOAc (2×150 mL). The combined organic layer was dried over Na2SO4, filtered and concentrated to a slurry (75 mL) which was stored in a refrigerator overnight. The slurry was filtered and the white solid product was washed with Et2O. The liquid filtrate was concentrated to a yellow slurry which was filtered and washed with Et2O to give more white solid product. The two batches of white solid were combined and dried in vacuo to give the title compound (8.6 g, 15.09 mmol, 86% yield) as a white solid. 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 8.0 (2H, d, J=8.2 Hz), 7.2 (2H, d, J=8.2 Hz), 5.3 (1H, d, J=4.6 Hz), 4.8 (1H, s), 4.7 (1H, s), 3.9 (3H, s), 2.6 (1H, td, J=10.8, 5.8 Hz), 2.1-2.2 (2H, m), 1.8-2.0 (4H, m), 1.7-1.8 (1H, m), 1.7 (3H, s), 1.5-1.7 (5H, m), 1.4-1.5 (5H, m), 1.3-1.4 (2H, m), 1.2-1.3 (2H, m), 1.1 (3H, s), 1.1-1.1 (1H, m), 1.0 (3H, s), 1.0 (3H, s), 1.0 (3H, br. s.), 1.0 (3H, br. s.). 13C NMR (CHLOROFORM-d) δ ppm 14.2, 15.4, 16.2, 19.2, 19.5, 20.8, 21.0, 24.7, 27.4, 29.0, 29.2, 33.3, 36.0, 37.2, 39.0, 39.0, 40.3, 41.5, 41.8, 47.8, 49.0, 49.2, 51.7, 52.6, 66.8, 71.3, 110.2, 121.3, 123.7, 127.6, 128.2, 129.8, 146.0, 148.4, 148.6, 166.9.

Quelle