(1beta,2beta)-17-(Acetyloxy)-1,2-dihydro-3'H-cyclopropa[1,2]pregna-1,4,6-triene-3,20-dione → 17alpha-Acetoxy-1alpha,2alpha-methylene-4-pregnene-3,20-dione

HRID 652271Notes

Reaction equation

HRID 652271 reaction equation
[C:1]([O:4][C@:5]1([C@:25]2([CH3:26])[C@H:11]([C@H:12]3[C@H:22]([CH2:23][CH2:24]2)[C@:20]2([CH3:21])[C:15](=[CH:16][C:17](=[O:28])[C@@H:18]4[CH2:27][C@@H:19]42)[CH:14]=[CH:13]3)[CH2:10][CH2:9]1)[C:6](=[O:8])[CH3:7])(=[O:3])[CH3:2]>[Pd].C([O-])([O-])=O.[Ca+2].CN(C)C=O>[C:1]([O:4][C@:5]1([C@:25]2([CH3:26])[C@H:11]([C@H:12]3[C@H:22]([CH2:23][CH2:24]2)[C@:20]2([CH3:21])[C:15](=[CH:16][C:17](=[O:28])[C@@H:18]4[CH2:27][C@@H:19]42)[CH2:14][CH2:13]3)[CH2:10][CH2:9]1)[C:6](=[O:8])[CH3:7])(=[O:3])[CH3:2]

Participants

4

Reactant 1

HCID 13519086(1beta,2beta)-17-(Acetyloxy)-1,2-dihydro-3'H-cyclopropa[1,2]pregna-1,4,6-triene-3,20-dione

Product 1

HCID 1351908817alpha-Acetoxy-1alpha,2alpha-methylene-4-pregnene-3,20-dione

Reagents, catalysts & solvents 2

HCID 12000666Calcium Palladium CarbonateCatalystHCID 6228DimethylformamideSolvent

Procedure

A solution of 60.0 g of 17α-acetoxy-1α,2α-methylene-4,6-pregnadiene-3,20-dione [R. Wiechert et al., Chem. Ber. 93: 1710 (1960)] in 1.25 1 of dimethylformamide is combined with 6.3 g of 10% Pd/CaCO3 and then hydrogenated. After a hydrogen absorption of 5.1 1, the catalyst is filtered off and the reaction solution stirred into ice water. The precipitate is suctioned off, worked up as usual, and the crude product is purified on 1.5 kg of silica gel with a pentane-acetone gradient (0-30% acetone). Yield: 34.3 g of 17α-acetoxy-1α,2α-methylene-4-pregnene-3,20-dione, mp 268°-270° C. [α]D =+215°.

Workup

  1. customAfter a hydrogen absorption of 5.1 1
  2. filtrationthe catalyst is filtered off
  3. customis purified on 1.5 kg of silica gel with a pentane-acetone gradient (0-30% acetone)
  4. customYield: 34.3 g of 17α-acetoxy-1α,2α-methylene-4-pregnene-3,20-dione, mp 268°-270° C. [α]D =+215°

Sources & evidence

ORD record
ord-2f07803788444daf870a82e1fbd330b3
Source dataset
uspto-grants-1987_06
Patent number
US04670427

Reaction notes

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