[OH:1][C:2]1[CH:3]=[C:4]([CH:15]=[CH:16][CH:17]=1)[C:5]([O:7]CC1C=CC=CC=1)=[O:6].C([O-])([O-])=O.[Cs+].[Cs+].Br[CH2:25][C:26]([O:28][C:29]([CH3:32])([CH3:31])[CH3:30])=[O:27]>CN(C=O)C.CCOC(C)=O.[Pd]>[C:29]([O:28][C:26](=[O:27])[CH2:25][O:1][C:2]1[CH:17]=[CH:16][CH:15]=[C:4]([C:5]([OH:7])=[O:6])[CH:3]=1)([CH3:32])([CH3:31])[CH3:30]To 7-2 (3.6 g, 16 mmol) in DMF (50 mL) was added Cs2CO3 (7.8 g, 238 mmol). After 15 min., tert-butyl bromoacetate (3.2 mL, 35 mmol) was added and the reaction mixture stirred for 20 hrs at ambient temperature. The reaction mixture was diluted with EtOAc and then washed with H2O, and brine, dried (MgSO4), and concentrated to give a yellow oil. The crude yellow oil (5.4 g, 15.8 mmol), 10% Pd/C (500 mg), and EtOAc (100 mL) was stirred under a hydrogen atmosphere (1 atm) for 20 hr. The reaction mixture was then filtered through a celite pad and the filtrate concentrated to give 7-3 as a white solid.
Wird geladen…