Ethanol → Vitamin D4

HRID 963186Notes

Reaction equation

HRID 963186 reaction equation
[CH3:1][C@@H:2]([C@@H:10]1[C@@:14]2([CH3:29])[CH2:15][CH2:16][C@@H:17]3[C@@:22]4([CH3:28])[CH2:23][CH2:24][C@H:25]([OH:27])[CH2:26][C:21]4=[CH:20][CH:19]=[C:18]3[C@@H:13]2[CH2:12][CH2:11]1)[CH2:3][CH2:4][C@@H:5]([CH:7]([CH3:9])[CH3:8])[CH3:6].O.C(O)C>C(OCC)C.C1C=CC=CC=1>[CH3:1][C@@H:2]([C@@H:10]1[C@@:14]2([CH3:29])[CH2:15][CH2:16][CH2:17]/[C:18](=[CH:19]\[CH:20]=[C:21]3\[CH2:26][C@@H:25]([OH:27])[CH2:24][CH2:23][C:22]\3=[CH2:28])/[C@@H:13]2[CH2:12][CH2:11]1)[CH2:3][CH2:4][C@@H:5]([CH:7]([CH3:8])[CH3:9])[CH3:6]

Participants

6

Reactant 3

HCID 702EthanolHCID 962WaterHCID 5326970Dihydroergosterol

Product 1

HCID 5460703Vitamin D4

Reagents, catalysts & solvents 2

HCID 241BenzeneSolventHCID 3283Diethyl EtherSolvent

Procedure

22,23-dihydroergosterol (VII) (2.0 g, 5.0 mmol) was dissolved in a solution of diethyl ether and benzene (4:1, 600 ml) and irradiated (Hannovia immersion lamp, 450 watts) with stirring under argon in a water-cooled quartz vessel for three hours. The solution was concentrated in vacuo to yield a gummy solid, which was redissolved in 100 ml. of ethanol and heated at reflux under argon for eight hours. Then, the solution was concentrated in vacuo and the residue was adsorbed on a silica gel column and eluted with 30% ethyl acetate in hexane to afford vitamin D4 (22,23-dihydroergocalciferol) (IX) with a yield of 1.2 g. (60%) and with the following characteristics: 1H NMR: (400 MHz, CDCl3), δppm 0.55 (3H, s, 18-H3) 0.78 (6H, dd, 26-H3 and 27-H3) 0.87 (3H, d, 21-H3) 0.93 (3H, d 28-H3) 3.94 (1H, m, 3-H) 4.82 (1H, m (sharp), 19-H), 5.04 (1H, m (sharp), 19-H), 6.04 (1H, d, 7-H) 6.24 (1H, d, 6-H).

Workup

  1. customirradiated (Hannovia immersion lamp, 450 watts)
  2. temperaturecooled quartz vessel for three hours
  3. concentrationThe solution was concentrated in vacuo
  4. customto yield a gummy solid, which
  5. dissolutionwas redissolved in 100 ml
  6. temperatureat reflux under argon for eight hours
  7. concentrationThen, the solution was concentrated in vacuo
  8. washeluted with 30% ethyl acetate in hexane

Sources & evidence

ORD record
ord-c3e77318209f44b187f6d07643c4b38e
Source dataset
uspto-grants-1998_06
Patent number
US05763428

Reaction notes

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