[CH3:1][N:2]1[C@H:11]2[C@@:6]([CH3:17])([C:7]3[CH:15]=[CH:14][C:13](Br)=[CH:12][C:8]=3[CH2:9][CH2:10]2)[CH2:5][CH2:4][C:3]1=[O:18].C([N-]C(C)C)(C)C.[Li+].C([Li])CCC.[CH3:32][S:33]SC>O1CCCC1.C(O)(=O)C>[CH3:1][N:2]1[C@H:11]2[C@@:6]([CH3:17])([C:7]3[CH:15]=[CH:14][C:13]([S:33][CH3:32])=[CH:12][C:8]=3[CH2:9][CH2:10]2)[CH2:5][CH2:4][C:3]1=[O:18](+)-(4aR)-(10bR)-4-methyl-8-bromo-10b-methyl-1,2,3,4,4a,5,6,10b-octahydrobenzo[f]quinolin-3-one (20.0 grams, 64.9 mmole, in 150 mL of tetrahydrofuran) was added to a freshly prepared solution of lithium diisopropylamide in 500 mL of tetrahydrofuran at -20° C. After standing 90 minutes in an ice bath, the resulting amide-enolate solution was cooled to -70° C. and added via cannula over 10 minutes to a freshly mixed solution of n-butyllithium (60.0 mL=2.54 M in hexane, 152 mmole, 2.34 equivalents) at -72 to -75° C. in 300 mL of tetrahydrofuran. The homogeneous solution was allowed to stir at approximately -75° C. for 45 minutes and quenched with dimethyldisulfide (11.0 mL, 123 mmole, 1.9 equiv) at approximately -75° C. After 30 minutes at -75° C., the mixture was treated with acetic acid (18 mL) and all volatiles removed under vacuum. The resulting white solid was treated with 300 mL of heptane-water (1:1, v/v) and the pH adjusted to 3 with 1N hydrogen sulfate. The biphasic mixture was filtered and the wet cake was washed with 1% aqueous sodium bicarbonate (2×50 mL portion) and water (200 mL). The material was dried at 50° C. under vacuum affording (+)-(4aR)-(10bR)-4-methyl-8-methylthio-10b-methyl-1,2,3,4,4a,5,6,10b-octahydrobenzo[f]quinolin-3-one (IR, NMR, MS). Calculated for C16H21NOS: C, 69.77; H, 7.69; N, 5.09. Found C, 69.70; H, 7.62; N, 5.06.
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