[H-].[Na+].[Na+].[I-].[C:5]([O:14][CH2:15][CH:16]=[CH2:17])(=[O:13])[CH2:6][C:7]([O:9][CH2:10][CH:11]=[CH2:12])=[O:8].Br[CH2:19][CH2:20][CH2:21][C:22]([C:24]1[C:29]([CH3:30])=[CH:28][C:27]([CH3:31])=[CH:26][C:25]=1[CH3:32])=[O:23].OP(O)(O)=O.[Br-].C([O-])(=O)CC([O-])=O>C1COCC1>[CH3:32][C:25]1[CH:26]=[C:27]([CH3:31])[CH:28]=[C:29]([CH3:30])[C:24]=1[C:22](=[O:23])[CH2:21][CH2:20][CH2:19][CH:6]([C:7]([O:9][CH2:10][CH:11]=[CH2:12])=[O:8])[C:5]([O:14][CH2:15][CH:16]=[CH2:17])=[O:13]To a slurry of NaH (60% in mineral oil, 0.36 g) and NaI (0.55 g) in dry THF (37 mL) was added diallyl malonate (3.2 g, 18.5 mmol). The resulting slurry was stirred at room temp. for 30 min., then 4-bromo-1-(2,4,6-trimethylphenyl)-1-butanone (1.0 g, 3.7mmol) was added. This mixture was heated at the reflux temperature for 18 h, cooled to room temp., and acidified with a 1M H3PO4 solution (10 mL). The resulting mixture was extracted with CH2Cl2 (2×100 mL). The combined organic phases were sequentially washed with a 1M H3PO4 solution (100 mL), and a saturated NaCl solution (50 ml), dried (MgSO4), and concentrated under reduced pressure (kugelrohr, 80° C., (4 mmHg)) to give a crude oil which was further purified using rotary chromatography (SiO2, gradient from 1% EtOAc/hexane to 5% EtOAc/hexane) to give starting bromide (0.34 g) followed by the desired malonate (0.36 g). The resultant compound is illustrated below and was used in the next step without further purification as described in example 1 step 4. ##STR43##
Wird geladen…