[CH2:1]([C:4]1([C:18]([O:20][CH3:21])=[O:19])[CH2:13][CH2:12][C:11]2[C:6](=[CH:7][CH:8]=[C:9]([C:14]([O:16][CH3:17])=[O:15])[CH:10]=2)[CH2:5]1)C=C.I([O-])(=O)(=O)=O.[Na+].[CH3:28][OH:29]>O.[Os](=O)(=O)(=O)=O>[O:29]=[CH:28][CH2:1][C:4]1([C:18]([O:20][CH3:21])=[O:19])[CH2:13][CH2:12][C:11]2[C:6](=[CH:7][CH:8]=[C:9]([C:14]([O:16][CH3:17])=[O:15])[CH:10]=2)[CH2:5]1
To a stirred solution of (±)-dimethyl 2-allyl-1,2,3,4-tetrahydronaphthalene-2,6-dicarboxylate from Step B (433 mg, 1.50 mmol) in MeOH (20 mL) and H2O (7 mL) was added osmium tetroxide (2.5 wt. % in t-BuOH, 1.07 mL, 0.105 mmol) and sodium periodate (964 mg, 4.51 mmol). The resulting mixture was stirred for 1 h at ambient temperature and a thick white precipitate quickly formed. After 70 min, the mixture was partitioned between dilute aqueous NaCl (100 mL) and EtOAc (200 mL). The organic layer was dried over Na2SO4, filtered, and concentrated in vacuo to give the title compound in sufficient purity for use in the next step. MS: m/z=291 (M+1).
Loading…
