N-Hydroxyphthalimide → HCID 22875686, compound

HRID 2258005Notes

Reaction equation

HRID 2258005 reaction equation
[C:1]([O:4][CH:5]1[CH2:31][CH2:30][C@@:29]2([CH3:32])[C:7](=[CH:8][CH2:9][C@@H:10]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:33])[C@H:11]3[CH2:12][CH2:13][C@@H:14]2[CH:15]([O:17][Si:18]([C:21]([CH3:24])([CH3:23])[CH3:22])([CH3:20])[CH3:19])[CH3:16])[CH2:6]1)(=[O:3])[CH3:2].[OH:34]N1C(=O)C2=CC=CC=C2C1=O>C(C(C)=O)C.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>[C:1]([O:4][CH:5]1[CH2:31][CH2:30][C@@:29]2([CH3:32])[C:7](=[CH:8][C:9](=[O:34])[C@@H:10]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:33])[C@H:11]3[CH2:12][CH2:13][C@@H:14]2[CH:15]([O:17][Si:18]([C:21]([CH3:22])([CH3:23])[CH3:24])([CH3:20])[CH3:19])[CH3:16])[CH2:6]1)(=[O:3])[CH3:2]

Participants

5

Reactant 2

HCID 10665N-HydroxyphthalimideHCID 54232237HCID 54232237, compound

Product 1

HCID 22875686HCID 22875686, compoundYield 32%

Reagents, catalysts & solvents 2

HCID 7187Benzoyl PeroxideCatalystHCID 6569Methyl Ethyl KetoneSolvent

Conditions

Temperature
40 °C

Procedure

To a solution of 3-acetoxy-20-tert-butyldimethylsilyloxy-pregn-5-ene (337 gm, 0.71 mol) in methyl ethyl ketone (4 L) was added N-hydroxyphthalimide (115.8 gm, 0.71 mol) and dibenzoyl peroxide (1.1 gm, 4.4 mmol). Air was bubbled through the reaction as the reaction was refluxed for 7.5 hr. Additional N-hydroxyphthalimide (9 gm) and dibenzoyl peroxide (0.1 gm) was added and reflux continued for 5 hr. The solvent was removed by rotoevaporation and methylene chloride (0.7 L) was added and warmed to 40° C. Upon cooling to room temperature, the suspension was filtered and the filtrate washed with methylene chloride (0.2 L). The filtrate was rotoevaporated and treated with pyridine (1.35 L) and acetic anhydride (135 mL). After stirring overnight, the solvent was removed by rotoevaporation and the dark orange oil dissolved in methanol (0.6 L). The mixture was heated to 50° C. and then cooled to room temperature. The solution was allowed to stand for 3 days and then cooled in an ice bath. The precipitant was filtered, washed with methanol, and dried to yield the title compound (110.6 gm, 32% yield). The filtrate was rotoevaporated to a dry gum to yield 253 gm of the crude product.

Workup

  1. customAir was bubbled through the reaction as the reaction
  2. temperaturewas refluxed for 7.5 hr
  3. additionAdditional N-hydroxyphthalimide (9 gm) and dibenzoyl peroxide (0.1 gm) was added
  4. temperaturereflux
  5. customThe solvent was removed by rotoevaporation and methylene chloride (0.7 L)
  6. additionwas added
  7. temperatureUpon cooling to room temperature
  8. filtrationthe suspension was filtered
  9. washthe filtrate washed with methylene chloride (0.2 L)
  10. additiontreated with pyridine (1.35 L) and acetic anhydride (135 mL)
  11. customthe solvent was removed by rotoevaporation
  12. dissolutionthe dark orange oil dissolved in methanol (0.6 L)
  13. temperatureThe mixture was heated to 50° C.
  14. temperaturecooled to room temperature
  15. waitto stand for 3 days
  16. temperaturecooled in an ice bath
  17. filtrationThe precipitant was filtered
  18. washwashed with methanol
  19. customdried

Sources & evidence

ORD record
ord-f9384a67ba884947a88aa1596ffc4387
Source dataset
uspto-grants-1997_08
Patent number
US05658922

Reaction notes

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