Ammonium Chloride → 6-Acetoxy-2-hydroxymethylbicyclo[3,3,0]octane

HRID 462788Notes

Reaction equation

HRID 462788 reaction equation
[C:1]([O:4][CH:5]1[CH2:12][CH2:11][CH:10]2[CH:6]1[CH2:7][CH2:8][CH:9]2[C:13](O)=[O:14])(=[O:3])[CH3:2].B#B.[Cl-].[NH4+]>O1CCCC1>[C:1]([O:4][CH:5]1[CH2:12][CH2:11][CH:10]2[CH:6]1[CH2:7][CH2:8][CH:9]2[CH2:13][OH:14])(=[O:3])[CH3:2]

Participants

5

Conditions

Temperature
-40 °C

Procedure

A solution of 6-acetoxy-2-carboxybicyclo[3,3,0]octane (3.2 g; prepared as described in Reference Example 5 and predominantly in the 2β-configuration) in tetrahydrofuran (30 ml) at -40° C. was treated with a solution of diborane in tetrahydrofuran (15 ml; 1M) under an argon atmosphere. The solution was stirred for 1 hour at -40° C. and then it was allowed to warm to 0° C. during 1 hour and was maintained at 0° C. for a further period of 150 minutes. The solution was then allowed to warm to 20° C. during 17 hours. The solution was then treated with aqueous ammonium chloride solution (10% w/v) and the mixture was concentrated in vacuo. The resulting residue was treated with ethyl acetate (100 ml) and washed with water (50 ml) and then with saturated aqueous sodium bicarbonate solution, and then was dried over anhydrous sodium sulphate. The solution was concentrated in vacuo to give an oil, which was subjected to medium pressure, short column chromatography on silica gel, eluting with a mixture of ethyl acetate and toluene (1:1 v/v), to give 6-acetoxy-2-hydroxymethylbicyclo[3,3,0]octane (2.8 g), predominantly in the 2β-configuration.

Workup

  1. customprepared
  2. temperatureto warm to 0° C. during 1 hour
  3. temperaturewas maintained at 0° C. for a further period of 150 minutes
  4. temperatureto warm to 20° C. during 17 hours
  5. concentrationthe mixture was concentrated in vacuo
  6. additionThe resulting residue was treated with ethyl acetate (100 ml)
  7. washwashed with water (50 ml)
  8. dry with materialwith saturated aqueous sodium bicarbonate solution, and then was dried over anhydrous sodium sulphate
  9. concentrationThe solution was concentrated in vacuo
  10. customto give an oil, which
  11. washeluting with a mixture of ethyl acetate and toluene (1:1 v/v)

Sources & evidence

ORD record
ord-488f0a4212784432820acc4ac22f7258
Source dataset
uspto-grants-1985_05
Patent number
US04517202

Reaction notes

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