Pyridine → 6alpha,7alpha-Diepoxypregn-4-en-3beta-yl acetate

HRID 1196317Notes

Reaction equation

HRID 1196317 reaction equation
[O:1]1[C:19]2=[C:20]3[C@:15]([CH3:22])([CH2:16][CH2:17][C@@H:18]2[OH:21])[C@@H:14]2[C@H:4]([C@H:5]4[C@:11]([CH3:23])([CH2:12][CH2:13]2)[C@@H:8]([CH2:9][CH3:10])[CH2:7][CH2:6]4)[C@@H:3]2[O:24][C@:2]123.N1C=CC=CC=1.[C:31](OC(=O)C)(=[O:33])[CH3:32]>C(Cl)Cl>[C:31]([O:21][C@H:18]1[CH2:17][CH2:16][C@@:15]2([CH3:22])[C:20]3[C@:2]4([O:1][C:19]1=3)[O:24][C@H:3]4[C@@H:4]1[C@@H:14]2[CH2:13][CH2:12][C@@:11]2([CH3:23])[C@H:5]1[CH2:6][CH2:7][C@@H:8]2[CH2:9][CH3:10])(=[O:33])[CH3:32]

Participants

5

Reactant 3

HCID 1049PyridineHCID 7918Acetic AnhydrideHCID 867457996alpha,7alpha-Diepoxypregn-4-en-3beta-ol

Product 1

HCID 867458006alpha,7alpha-Diepoxypregn-4-en-3beta-yl acetateYield 90%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a mixture of 0.084 g (0.189 mmole) of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α;6α,7α-diepoxypregn-4-en-3β-ol, 0.5 ml (6.18 mmoles) of dry pyridine and 5 ml of methylene chloride was gradually added 0.1 ml (1.06 mmoles) of acetic anhydride dropwise at a temperature of 0° C. and the solution was stirred at room temperature for 8 hours. The reaction mixture thus obtained was diluted with methylene chloride and washed with saturated aqueous copper (II) sulfate solution. The aqueous layer (washings) was extracted with methylene chloride and the extract was combined with the organic layer. The resulting mixture was washed with water and aqueous sodium chloride solution in that order and dired over magnesium sulfate. The solvent was then distilled off under reduced pressure and the residue was purified by silica gel chromatography (eluent: ethyl acetate-hexane: 1:10, v/v) to recover 0.083 g of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α;6α,7α-diepoxypregn-4-en-3β-yl acetate (yield: 90%).

Workup

  1. additionTo a mixture of 0.084 g (0.189 mmole) of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α
  2. customdropwise at a temperature of 0° C.
  3. customThe reaction mixture thus obtained
  4. washwashed with saturated aqueous copper (II) sulfate solution
  5. extractionThe aqueous layer (washings) was extracted with methylene chloride
  6. washThe resulting mixture was washed with water and aqueous sodium chloride solution in that order
  7. distillationThe solvent was then distilled off under reduced pressure
  8. customthe residue was purified by silica gel chromatography (eluent
  9. customethyl acetate-hexane: 1:10, v/v) to recover 0.083 g of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α

Sources & evidence

ORD record
ord-f5fcedadc12a445fb90b776e58929db0
Source dataset
uspto-grants-1992_05
Patent number
US05112998

Reaction notes

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