Sulfuric Acid → HCID 22796788, compound

HRID 838893Notes

Reaction equation

HRID 838893 reaction equation
[OH:1][C@@H:2]([C:26]#[C:27][CH3:28])[CH2:3][C@:4]1([CH3:25])[CH2:13][CH2:12][C:11]2[C:6](=[C:7]([CH3:24])[C:8]([CH3:23])=[C:9]([O:15][CH2:16][C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=3)[C:10]=2[CH3:14])[O:5]1.CCOCC.[H-].COCCO[Al+]OCCOC.[Na+].[H-].OS(O)(=O)=O>C(Cl)(Cl)Cl>[OH:1][C@@H:2](/[CH:26]=[CH:27]/[CH3:28])[CH2:3][C@:4]1([CH3:25])[CH2:13][CH2:12][C:11]2[C:6](=[C:7]([CH3:24])[C:8]([CH3:23])=[C:9]([O:15][CH2:16][C:17]3[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=3)[C:10]=2[CH3:14])[O:5]1

Participants

6

Reactant 4

HCID 1118Sulfuric AcidHCID 3283Diethyl Ether2×HCID 14369250HCID 14369250, compoundHCID 21584525Sodium bis(2-methoxyethoxy)aluminiumhydride

Product 1

HCID 22796788HCID 22796788, compound

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent

Procedure

To a solution of 5.0 g. (13.32 mmol) of 2(S)-[2(R)-hydroxy-3-pentynyl]-2,5,7,8-tetramethyl-6-benzyloxy-chroman in 50 ml. of dry ether was carefully added 4.06 ml. of sodium bis(2-methoxyethoxy)-aluminum hydride (29 mg. - atm. of hydrogen) in 10 ml. of dry ether. The resulting solution was refluxed under argon for 17 hours. The solution was cooled in an ice bath and 10% by volumn aqueous H2SO4 solution (100 ml.) was carefully added. It was filtered, washed with ether and water. The aqueous phase was again extracted with ether (3 × 100 ml.). The combined ether phase was washed with saturated aqueous NaHCO3 solution (3 × 50 ml.) and water (3 × 50 ml.) and dried over MgSO4. Evaporation of ether to dryness at reduced pressure yielded 5.206 g. of crude product which was crystallized from petroleum ether (b.p. 30°-60° C.) to give 4.23 g. of 2(S)-[2(R)-hydroxy-3(E)-pentynyl]-2,5,7,8-tetramethyl-6-benzyloxychroman as white needles, m.p. 68°-70° C. [α]D25 -24.02° (CHCl3).

Workup

  1. temperatureThe resulting solution was refluxed under argon for 17 hours
  2. temperatureThe solution was cooled in an ice bath
  3. filtrationIt was filtered
  4. washwashed with ether and water
  5. extractionThe aqueous phase was again extracted with ether (3 × 100 ml.)
  6. washThe combined ether phase was washed with saturated aqueous NaHCO3 solution (3 × 50 ml.) and water (3 × 50 ml.)
  7. dry with materialdried over MgSO4
  8. customEvaporation of ether to dryness at reduced pressure
  9. customyielded 5.206 g
  10. customof crude product which was crystallized from petroleum ether (b.p. 30°-60° C.)
  11. customto give 4.23 g

Sources & evidence

ORD record
ord-056569c65c314cf9a16ad02c6bee55dd
Source dataset
uspto-grants-1978_06
Patent number
US04093632

Reaction notes

Loading…