Pyridine → 20-(5,5-Dimethyl-1,3-dioxan-2-yl)-1alpha, 2alpha-epoxypregna-5,7-dien-3beta-yl acetate

HRID 1196325Notes

Reaction equation

HRID 1196325 reaction equation
[C:1]([O:4][C@H:5]1[C@@H:31]2[O:32][C@@H:30]2[C@@:29]2([CH3:33])[C:7](=[CH:8][C@@H:9](O)[C@@H:10]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:34])[C@H:11]3[CH2:12][CH2:13][C@@H:14]2[CH:15]([CH:17]2[O:22][CH2:21][C:20]([CH3:24])([CH3:23])[CH2:19][O:18]2)[CH3:16])[CH2:6]1)(=[O:3])[CH3:2].N1C=CC=CC=1.CS(Cl)(=O)=O.C(OCC)(=O)C.CCCCCC>CN(C)C1C=CN=CC=1.C(Cl)Cl>[C:1]([O:4][C@H:5]1[C@@H:31]2[O:32][C@@H:30]2[C@@:29]2([CH3:33])[C:7](=[CH:8][CH:9]=[C:10]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:34])[C@H:11]3[CH2:12][CH2:13][C@@H:14]2[CH:15]([CH:17]2[O:18][CH2:19][C:20]([CH3:24])([CH3:23])[CH2:21][O:22]2)[CH3:16])[CH2:6]1)(=[O:3])[CH3:2]

Participants

7

Reactant 4

HCID 1049PyridineHCID 31297Methanesulfonyl chlorideHCID 21226206Ethyl acetate hexaneHCID 8674580220-(5,5-Dimethyl-1,3-dioxan-2-yl)-1alpha, 2alpha-epoxy-7alpha-hydroxypregna-5-en-3beta-yl acetate

Product 1

HCID 8674580520-(5,5-Dimethyl-1,3-dioxan-2-yl)-1alpha, 2alpha-epoxypregna-5,7-dien-3beta-yl acetateYield 54.2%

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent2×

Procedure

To a mixture of 49.0 mg (0.1 mmole) of 20-(5,5-di-methyl-1,3-dioxan-2-yl)-1α,2α-epoxy-7α-hydroxypregn-5-en-3β-yl acetate, 0.24 ml (3 mmoles) of pyridine, 0.5 mg (0.004 mmole) of 4-(dimethylamino)pyridine and 10 ml of methylene chloride was added 0.10 ml (1.3 mmoles) of methanesulfonyl chloride dropwise at a temperature of 0° C. and the mixture was stirred at room temperature for 12 hours. The reaction mixture was diluted with 20 ml of methylene chloride, then washed successively with cold 1N-hydrochloric acid, water, aqueous sodium hydrogen carbonate solution and aqueous sodium chloride solution, and dried over magnesium sulfate. The solvent was then distilled off under reduced pressure. Finally the residue was purified by silica gel chromatography (eluent: ethyl acetate-hexane=1:10, v/v) to give 25.5 mg of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α-epoxypregna-5,7-dien-3β-yl acetate (yield: 54%). The 1H-NMR spectrum of this product was in agreement with that of the 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α-epoxypregna-5,7-dien-3β-yl acetate obtained in Example 17.

Workup

  1. washwashed successively with cold 1N-hydrochloric acid, water, aqueous sodium hydrogen carbonate solution and aqueous sodium chloride solution
  2. dry with materialdried over magnesium sulfate
  3. distillationThe solvent was then distilled off under reduced pressure
  4. customFinally the residue was purified by silica gel chromatography (eluent

Sources & evidence

ORD record
ord-3c8e1b4b58b7428a8050296636207402
Source dataset
uspto-grants-1992_05
Patent number
US05112998

Reaction notes

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