Benzyl Bromide → (3S)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]azetidin-2-one

HRID 247704Notes

Reaction equation

HRID 247704 reaction equation
[H-].[Na+].C([N:10]1[C@H:13](CCO)[C@@H:12]([C@H:17]([O:19][Si:20]([C:23]([CH3:26])([CH3:25])[CH3:24])([CH3:22])[CH3:21])[CH3:18])[C:11]1=[O:27])C1C=CC=CC=1.C(Br)C1C=CC=CC=1>O.C1COCC1.CN(C)C=O>[Si:20]([O:19][C@@H:17]([C@@H:12]1[CH2:13][NH:10][C:11]1=[O:27])[CH3:18])([C:23]([CH3:26])([CH3:24])[CH3:25])([CH3:22])[CH3:21]

Participants

7

Reactant 3

HCID 7498Benzyl BromideHCID 24758Sodium hydrideHCID 139595691-benzyl-3(S)-[1(R)-t-butyldimethylsilyloxyethyl]-4(R)-(2-hydroxyethyl)-2-azetidinone

Product 1

HCID 10130795(3S)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]azetidin-2-oneYield 58%

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6228DimethylformamideSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

There were added 1 ml of THF and 0.6 ml of dimethylformamide to 13 mg (0.26 mmol) of sodium hydride (oiliness: 50%), to which 2 ml of a THF solution of 64 mg (0.18 mmol) of 1-benzyl-3(S)-[1(R)-t-butyldimethylsilyloxyethyl]-4(R)-(2-hydroxyethyl)-2-azetidinone on the ice bath and the mixture was stirred for 10 minutes. Thereto 0.03 ml (0.25 mmol) of benzyl bromide was added and the mixture was stirred at room temperature for a night. The reaction mixture was added with water, extracted three times with diethyl ether, and the obtained extract was washed with a saturated aqueous solution of sodium chloride, dried with anhydrous magnesium sulfate and concentrated. The obtained residue was purified by 10 g of silica gel-column chromatography (eluent; hexane:diethyl ether=1:1) to give 46 mg of 1-benzyl-4(R)-2-benzyloxyethyl)-3(S)-[1(R)-t-butyldimethylsilyloxyethyl]-2-azetidinone (yield: 58%).

Workup

  1. extractionextracted three times with diethyl ether
  2. extractionthe obtained extract
  3. washwas washed with a saturated aqueous solution of sodium chloride
  4. dry with materialdried with anhydrous magnesium sulfate
  5. concentrationconcentrated
  6. customThe obtained residue was purified by 10 g of silica gel-column chromatography (eluent; hexane:diethyl ether=1:1)

Sources & evidence

ORD record
ord-5529d26c64614193a5c8a7a4375d5f6c
Source dataset
uspto-grants-1987_11
Patent number
US04709064

Reaction notes

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