Carbon tetrabromide → HCID 12790115, compound

HRID 1701493Notes

Reaction equation

HRID 1701493 reaction equation
[C:1]([O:4][C@@H:5]1[C@@:25]2([CH3:26])[C:9](=[CH:10][CH2:11][C@@H:12]3[C@@H:24]2[CH2:23][CH2:22][C@@:21]2([CH3:27])[C@H:13]3[CH2:14][CH2:15][C@@H:16]2[C@H:17]([CH3:20])[CH2:18]O)[CH2:8][C@@H:7]([O:28][C:29](=[O:31])[CH3:30])[CH2:6]1)(=[O:3])[CH3:2].C(Br)(Br)(Br)[Br:33].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>CCOCC>[Br:33][CH2:18][C@@H:17]([CH3:20])[C@@H:16]1[C@:21]2([CH3:27])[C@H:13]([C@H:12]3[C@H:24]([CH2:23][CH2:22]2)[C@:25]2([CH3:26])[C:9]([CH2:8][C@@H:7]([O:28][C:29](=[O:31])[CH3:30])[CH2:6][C@@H:5]2[O:4][C:1](=[O:3])[CH3:2])=[CH:10][CH2:11]3)[CH2:14][CH2:15]1

Participants

5

Reactant 3

HCID 11205Carbon tetrabromideHCID 11776TriphenylphosphineHCID 12790110HCID 12790110, compound

Product 1

HCID 12790115HCID 12790115, compoundYield 88.9%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

A solution of 0.54 g of (20S)-1α,3β-diacetoxy-21-hydroxy-20-methyl-pregn-5-ene and 0.825 g of carbon tetrabromide in 10 ml. of ether was treated with 0.625 g of triphenylphosphine and the mixture was left at room temperature for 16 hours. After dilution with ether, insoluble material was filtered off. The filtrate was concentrated in vacuo and the residue was chromatographed on 15 g of silica gel using hexane/ether (9:1) for the elution. There was obtained 0.55 g of uniform (20S)-21-bromo-1α,3β-diacetoxy-20-methyl-pregn-5-ene in the form of a colourless powder of melting point 75°-76° C.; [α]D =-13.8° (c=0.5 in chloroform).

Workup

  1. filtrationAfter dilution with ether, insoluble material was filtered off
  2. concentrationThe filtrate was concentrated in vacuo
  3. customthe residue was chromatographed on 15 g of silica gel
  4. washfor the elution

Sources & evidence

ORD record
ord-43321947cb9741db9db334b49d5586ec
Source dataset
uspto-grants-1980_03
Patent number
US04193921

Reaction notes

Loading…