Hydrogen Bromide → 2alpha-Bromo-5alpha-cholestan-3-one

HRID 839766Notes

Reaction equation

HRID 839766 reaction equation
[CH3:1][CH:2]([CH2:4][CH2:5][CH2:6][C@H:7]([C@@H:9]1[C@:26]2([CH3:27])[C@H:12]([C@H:13]3[C@H:23]([CH2:24][CH2:25]2)[C@:21]2([CH3:22])[C@H:16]([CH2:17][C:18](=[O:28])[CH2:19][CH2:20]2)[CH2:15][CH2:14]3)[CH2:11][CH2:10]1)[CH3:8])[CH3:3].CCOCC.[BrH:34].BrBr>C(O)(=O)C.C(Cl)Cl>[Br:34][C@@H:19]1[CH2:20][C@@:21]2([CH3:22])[C@@H:16]([CH2:15][CH2:14][C@@H:13]3[C@@H:23]2[CH2:24][CH2:25][C@@:26]2([CH3:27])[C@H:12]3[CH2:11][CH2:10][C@@H:9]2[C@H:7]([CH3:8])[CH2:6][CH2:5][CH2:4][CH:2]([CH3:1])[CH3:3])[CH2:17][C:18]1=[O:28]

Participants

7

Reactant 4

HCID 260Hydrogen BromideHCID 3283Diethyl EtherHCID 24408BromineHCID 921285alpha-Cholestan-3-one

Product 1

HCID 2238572alpha-Bromo-5alpha-cholestan-3-one

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolvent3×HCID 6344DichloromethaneSolvent

Procedure

50 g. of 5α-cholestan-3-one is dissolved in 750 ml. of acetic acid and 5000 ml. of ether, combined with 1 ml. of hydrobromic acid in acetic acid (37% strength), and gradually added dropwise to a solution of 22 g. of bromine in 50 ml. of acetic acid. The mixture is agitated for another 30 minutes, diluted with methylene chloride, and washed in succession with water, sodium bicarbonate solution, and water. After drying and evaporation, 61.5 g. of crude 2α-bromo-5α-cholestan-3-one is obtained.

Workup

  1. washwashed in succession with water, sodium bicarbonate solution, and water
  2. customAfter drying
  3. customevaporation, 61.5 g

Sources & evidence

ORD record
ord-c02d6ab0dfc34c0f8151e296a519c6db
Source dataset
uspto-grants-1978_06
Patent number
US04097334

Reaction notes

Loading…