[C:1]1([C:7]2[C:11]3[C:12](=[O:16])[CH2:13][CH2:14][CH2:15][C:10]=3[O:9][N:8]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C([N-]C(C)C)(C)C.[Li+].Br[CH2:26][C:27]([O:29][CH2:30][CH3:31])=[O:28].O>O1CCCC1.CCOCC>[CH2:30]([O:29][C:27](=[O:28])[CH2:26][CH:13]1[C:12](=[O:16])[C:11]2[C:7]([C:1]3[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=3)=[N:8][O:9][C:10]=2[CH2:15][CH2:14]1)[CH3:31]
In 115 ml anhydrous tetrahydrofuran was dissolved 2.44 g of 6,7-dihydro-3-phenyl-1,2-benzisoxazol-4(5H)-one under nitrogen. The solution was cooled to -78° C. and 11.5 ml lithium diisopropylamide was added dropwise. The resultant solution was stirred for 15 minutes at -78° C. and ethyl bromoacetate (2.6 ml) was added. Upon warming to room temperature, the reaction mixture was poured into water and ether. The layers were separated and the aqueous phase was extracted three times with dichloromethane and once with ether. The combined organic layers were washed with brine and dried (MgSO4). Flash column chromatography (30% ethyl acetate/hexane) gave 2.94 g of 4,5,6,7-tetrahydro-4-oxo-3-phenyl-1,2-benzisoxazol-5-acetic acid ethyl ester
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