Water → 1 Alpha,25-dihydroxycholesterol

HRID 2199019Notes

Reaction equation

HRID 2199019 reaction equation
[CH3:1][C:2](=[CH: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:16]([CH2:17][C@@H:18]([OH:29])[CH2:19][C@@H:20]2[OH:28])=[CH:15][CH2:14]3)[CH2:11][CH2:10]1)[CH3:8])[CH3:3].[OH2:30].[BH4-].[Na+]>O1CCCC1>[OH:28][C@@H:20]1[C@@:21]2([CH3:22])[C:16](=[CH: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][C:2]([OH:30])([CH3:3])[CH3:1])[CH2:17][C@@H:18]([OH:29])[CH2:19]1

Participants

5

Reactant 3

HCID 962WaterHCID 4311764Sodium borohydrideHCID 53821161Cholesta-5,24-diene-1alpha,3beta-diol

Product 1

HCID 1911241 Alpha,25-dihydroxycholesterolYield 85%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a cooled, stirred solution of 4.05 g (10.1 mmol) of cholesta-5,24-diene-1α,3β-diol in 53 ml of tetrahydrofuran in an ice bath was added 33 ml of water followed by 4.0 g (12.5 mmol) of mercuric acetate. The bath was removed. After 2 hr., the reaction was still incomplete (tlc) so 0.4 g (1.3 mmol) of mercuric acetate was added. After 4 hr., 800 mg (21.1 mol) of sodium borohydride was added, followed after 30 min. by 190 ml of saturated brine and extraction of the resulting suspension with 5×50 ml of methylene chloride. The organic phases were backwashed with 20 ml of brine, dried (Na2SO4), filtered and evaporated. The residue was chromatographed on 400 g of silica gel. Elution with 5% methanol--chloroform and combination of fractions according to tlc (10% methanol--chloroform) afforded 3.60 g (85%) of 1α,25-dihydroxycholesterol, mp 165°- 167° C.

Workup

  1. customThe bath was removed
  2. additionwas added
  3. waitAfter 4 hr
  4. extractionfollowed after 30 min. by 190 ml of saturated brine and extraction of the resulting suspension with 5×50 ml of methylene chloride
  5. dry with materialdried (Na2SO4)
  6. filtrationfiltered
  7. customevaporated
  8. customThe residue was chromatographed on 400 g of silica gel
  9. washElution with 5% methanol

Sources & evidence

ORD record
ord-de8987a2043c4c26b86093bda00dfc67
Source dataset
uspto-grants-1982_11
Patent number
US04360470

Reaction notes

Loading…