Smilagenone → epi-Sarsasapogenin

HRID 2238462Notes

Reaction equation

HRID 2238462 reaction equation
C(O[AlH-](OC(C)(C)C)OC(C)(C)C)(C)(C)C.[Li+].[CH3:18][C@H:19]1[CH2:47][O:46][C@@:22]2([O:26][C@H:25]3[CH2:27][C@H:28]4[C@@H:33]5[CH2:34][CH2:35][C@@H:36]6[CH2:42][C:40](=[O:41])[CH2:39][CH2:38][C@:37]6([CH3:43])[C@H:32]5[CH2:31][CH2:30][C@:29]4([CH3:44])[C@H:24]3[C@@H:23]2[CH3:45])[CH2:21][CH2:20]1>C1COCC1>[CH3:18][C@@H:19]1[CH2:47][O:46][C@@:22]2([O:26][C@H:25]3[CH2:27][C@H:28]4[C@@H:33]5[CH2:34][CH2:35][C@@H:36]6[CH2:42][C@H:40]([OH:41])[CH2:39][CH2:38][C@:37]6([CH3:43])[C@H:32]5[CH2:31][CH2:30][C@:29]4([CH3:44])[C@H:24]3[C@@H:23]2[CH3:45])[CH2:21][CH2:20]1

Participants

4

Reactant 2

HCID 160498SmilagenoneHCID 16684435Lithium tritertbutoxyaluminohydride

Product 1

HCID 12304430epi-SarsasapogeninYield 82.9%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-26.5 °C

Procedure

A solution of lithium tri-tert-butoxyaluminohydride in THF (1M, 41.71 kg) was added (over ca. 2 hours) to a stirred solution of sarsasapogenone (17.38 kg,) in dry THF (ca 70 kg) at −23 to −30° C. under dry nitrogen. The process line was washed with THF and the mixture stirred at −23 to −30° C. for ca. 3 hours. The resulting solution was carefully quenched with aqueous aqueous sodium sulfate solution (5.67 kg in 28.67 kg of water). The inorganic salts were removed by filtration and washed with THF (184 kg). Water (63.18 kg) was added and the bulk of the THF was removed by distillation. Additional water (126.44 kg) was added and the product isolated by filtration. The product was washed with water (2×17.3.8 kg) and acetone (4×13.73 kg). The product was dried at 35-40° C. to afford episarsasapogenin (14.48 kg).

Workup

  1. washThe process line was washed with THF
  2. customThe resulting solution was carefully quenched with aqueous aqueous sodium sulfate solution (5.67 kg in 28.67 kg of water)
  3. customThe inorganic salts were removed by filtration
  4. washwashed with THF (184 kg)
  5. additionWater (63.18 kg) was added
  6. customthe bulk of the THF was removed by distillation
  7. additionAdditional water (126.44 kg) was added
  8. customthe product isolated by filtration
  9. washThe product was washed with water (2×17.3.8 kg) and acetone (4×13.73 kg)
  10. customThe product was dried at 35-40° C.

Sources & evidence

ORD record
ord-0173458548414fada522a6177c2b6977
Source dataset
uspto-grants-2010_05
Patent number
US07718792B2

Reaction notes

Loading…