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

HRID 1901446

Reaction equation

HRID 1901446 reaction equation
C(=O)([O-])[O-].[Cs+].[Cs+].[Si:7]([O:14][CH2:15][C@H:16]1[NH:19][C:18](=[O:20])[C@H:17]1[NH:21][C:22]([C:35]1[CH:40]=[CH:39][CH:38]=[CH:37][CH:36]=1)([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:10]([CH3:13])([CH3:12])[CH3:11])([CH3:9])[CH3:8].Br[CH2:42][C:43]([O:45][CH2:46][C:47]1[CH:52]=[CH:51][C:50]([O:53][CH3:54])=[CH:49][CH:48]=1)=[O:44]>C(#N)C.CN(C)C=O>[Si:7]([O:14][CH2:15][C@H:16]1[N:19]([CH2:42][C:43]([O:45][CH2:46][C:47]2[CH:48]=[CH:49][C:50]([O:53][CH3:54])=[CH:51][CH:52]=2)=[O:44])[C:18](=[O:20])[C@H:17]1[NH:21][C:22]([C:35]1[CH:36]=[CH:37][CH:38]=[CH:39][CH:40]=1)([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:10]([CH3:13])([CH3:12])[CH3:11])([CH3:9])[CH3:8]

Participants

6

Reactant 3

HCID 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 114.7%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 6342AcetonitrileSolvent

Procedure

Cesium carbonate (1.58 g) was added to a stirred solution of (3S,4S)-4-t-butyldimethylsilyloxymethyl-3-tritylaminoazetidin-2-one (1.45 g) (IV) (H. Mastalerz et al., J. Med. Chem., 1988, 31, 1190-1196) in a mixture of acetonitrile (44 ml) and dimethylformamide (35 ml). 4-Methoxybenzyl bromoacetate (1.44 g) was then added and the mixture stirred at room temperature for 48 h. The mixture was then partitioned between ethyl acetate and water, the organic phase was washed four times with water, and then with brine. The solution was dried over magnesium sulphate and evaporated. The title compound (2.29 g) was isolated by column chromatography of the residue (Silica gel, 3:1 hexane:ethyl acetate as eluent). [α]D21 -9.0°; νmax (CHCl3) 3352, and 1755 cm-1 ; δ(CDCl3) -0.04 (3H, s), 0.00 (3H, s), 0.88 (9H, s), 1.69 (1H, br s), 2.54 (1H, dd, J 3.33 and 11.68 Hz), 3.19 (1H, dd, J 2.05 and 11.68 Hz), 3.38 (1H, m), 3.51 (1H, d, J 17.98 Hz), 3.90 (3H, s), 4.46 (1H, d, J 17.98 Hz), 4.54 (1H, m), 5.06 (1H, d, J 11.79 Hz), 5.15 (1H, d, J 11.81 Hz), 6.94 (2H, d, J 8.68 Hz), 7.2-7.65 (17H, m).

Workup

  1. customThe mixture was then partitioned between ethyl acetate and water
  2. washthe organic phase was washed four times with water
  3. dry with materialThe solution was dried over magnesium sulphate
  4. customevaporated

Sources & evidence

ORD record
ord-7e08db2806d44960a7f2b5894ff09452
Source dataset
uspto-grants-1996_11
Patent number
US05578591

Linked notes

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