Dimethylformamide → 4-Methoxybenzyl 2-[(3S,4S)-4-t-Butyldimethylsilyloxymethyl-2-oxo-3-tritylaminoazetidin-1-yl]acetate

HRID 1901445

Reaction equation

HRID 1901445 reaction equation
[Si:1]([O:8][CH2:9][C@H:10]1[NH:13][C:12](=[O:14])[C@H:11]1[NH:15][C:16]([C:29]1[CH:34]=[CH:33][CH:32]=[CH:31][CH:30]=1)([C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=1)[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].CN(C=O)C.C(=O)([O-])[O-].[Cs+].[Cs+].Br[CH2:47][C:48]([O:50][CH2:51][C:52]1[CH:57]=[CH:56][C:55]([O:58][CH3:59])=[CH:54][CH:53]=1)=[O:49]>C(#N)C.C(OCC)(=O)C>[Si:1]([O:8][CH2:9][C@H:10]1[N:13]([CH2:47][C:48]([O:50][CH2:51][C:52]2[CH:53]=[CH:54][C:55]([O:58][CH3:59])=[CH:56][CH:57]=2)=[O:49])[C:12](=[O:14])[C@H:11]1[NH:15][C:16]([C:29]1[CH:30]=[CH:31][CH:32]=[CH:33][CH:34]=1)([C:23]1[CH:24]=[CH:25][CH:26]=[CH:27][CH:28]=1)[C:17]1[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]

Participants

7

Reactant 4

HCID 6228DimethylformamideHCID 10796Cesium carbonateHCID 132332344-Methoxybenzyl 2-bromoacetateHCID 13859068(3S,4S)-4-t-Butyldimethylsilyloxymethyl-3-tritylaminoazetidinone

Product 1

HCID 702000314-Methoxybenzyl 2-[(3S,4S)-4-t-Butyldimethylsilyloxymethyl-2-oxo-3-tritylaminoazetidin-1-yl]acetateYield 76%

Reagents, catalysts & solvents 2

HCID 6342AcetonitrileSolventHCID 8857Ethyl AcetateSolvent

Procedure

(3S,4S)-4-t-Butyldimethylsilyloxymethyl-3-tritylaminoazetidinone (IV), (1.67 g) [H. Mastalerz et al., J. Med. Chem., 1988, 31, 1190] as a suspension in acetonitrile (40 ml) was treated with DMF (20 ml) to obtain a clear solution. Cesium carbonate (1.29 g) followed by 4-methoxybenzyl bromoacetate (1.19 g) were added and the mixture vigorously stirred overnight. T.l.c. analysis showed no starting material, the solution was diluted with ethyl acetate and washed with water (4×), brine and then dried. Removal of solvent in vacuo and purification by flash chromatography afforded the title compound as a pale yellow foam, (1.744 g, 76%), νmax (CH2Cl2) 1760 and 1744 cm-1 ; δH (CDCl3) -0.06 and -0.13 (6H, 2s), 0.81 (9H, s), 1.60 (1H, brs), 2.44 (1H, dd, J 3.3, 11.7 Hz), 3.1 (1H, dd, 2.2, 11.7Hz), 3.29 (1H, m), 3.41 (1H, d, J 18.0 Hz), 3.80 (3H, s), 4.36 (1H, d, J 18.0 Hz), 4.45 (1H, m), 4.97 and 5.05 (2H, ABq, J 11.8 Hz), 6.85 (2H, d, J 8.7 Hz), 7.16-7.30 (15H, m) and 7.52 (2H, d, J 8.7 Hz); [mass spectrum: MH+ (651)].

Workup

  1. customto obtain a clear solution
  2. additionwere added
  3. customthe mixture vigorously stirred overnight
  4. washwashed with water (4×), brine
  5. customdried
  6. customRemoval of solvent
  7. customin vacuo and purification by flash chromatography

Sources & evidence

ORD record
ord-ff352387695f42aab9c2377bb94448ce
Source dataset
uspto-grants-1996_11
Patent number
US05578591

Linked notes

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