Hydrochloric Acid → 6(S)-Tert-butoxycarbonylamino-8,8-dimethyl-5(S)-hydroxy-10-triisopropylsilyloxydec-1-ene

HRID 863233Notes

Reaction equation

HRID 863233 reaction equation
Br[CH2:2][CH2:3][CH:4]=[CH2:5].[Mg].[C:7]([O:11][C:12]([NH:14][C@@H:15]([CH2:18][C:19]([CH3:34])([CH3:33])[CH2:20][CH2:21][O:22][Si:23]([CH:30]([CH3:32])[CH3:31])([CH:27]([CH3:29])[CH3:28])[CH:24]([CH3:26])[CH3:25])[CH:16]=[O:17])=[O:13])([CH3:10])([CH3:9])[CH3:8].Cl>O1CCCC1>[C:7]([O:11][C:12]([NH:14][C@@H:15]([CH2:18][C:19]([CH3:33])([CH3:34])[CH2:20][CH2:21][O:22][Si:23]([CH:24]([CH3:25])[CH3:26])([CH:27]([CH3:28])[CH3:29])[CH:30]([CH3:32])[CH3:31])[C@@H:16]([OH:17])[CH2:5][CH2:4][CH:3]=[CH2:2])=[O:13])([CH3:10])([CH3:9])[CH3:8]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 21241Homoallyl bromideHCID 5462224MagnesiumHCID 228823952(S)-Tert-butoxycarbonylamino-6-triisopropylsilyloxy-4,4-dimethyl-hexanal

Product 1

HCID 228825826(S)-Tert-butoxycarbonylamino-8,8-dimethyl-5(S)-hydroxy-10-triisopropylsilyloxydec-1-ene

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

The Grignard reagent is prepared from 3.70 ml of 4-bromo-1-butene and 880 mg of magnesium powder in 50 ml of tetrahydrofuran at 55° C. This solution is then added dropwise to a solution of 3.0 g of 2(S)-tert-butoxycarbonylamino-6-triisopropylsilyloxy-4,4-dimethyl-hexanal (Example 1g)) in 25 ml of tetrahydrofuran at 5°-10° C. 1 h after the end of the addition, the mixture is poured onto a 0.1N hydrochloric acid solution, extracted with methylene chloride and concentrated. The crude product contains the two 5(S):5(R) diastereomers in a ratio of about 5:1. The title compound (non-polar diastereomer) is obtained by purification over 250 g of silica gel (mobile phase E): Rf (E)=0.30.

Workup

  1. addition1 h after the end of the addition
  2. extractionextracted with methylene chloride
  3. concentrationconcentrated

Sources & evidence

ORD record
ord-c69e7384e9704f2aab5c0c02bfff7f1e
Source dataset
uspto-grants-1998_02
Patent number
US05719141

Reaction notes

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