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

HRID 581206

Reaction equation

HRID 581206 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

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-62ab2a671d1041e3a046ded22a219a9b
Source dataset
uspto-grants-1999_07
Patent number
US05919925

Linked notes

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