Reaction Steps
To a solution of (1R,2R,4aS,8aS)-1-{[(3-methoxyphenyl)sulfanyl]methyl}-2,5,5,8a-tetramethyl-decahydronaphthalen-2-ol (12b) (2.5 g, 6.9 mmol) in CH2Cl2 (70 mL), cooled to −78° C., a solution of SnCl4 (3.22 mL, 27.6 mmol) in CH2Cl2 (30 mL) was added dropwise. The mixture was stirred at −78° C. for 4 h. The reaction was quenched with water (100 mL), and the organic layer was separated, dried (Na2SO4), and concentrated. Purification by column chromatography on silica gel (Hexanes/toluene, 2:1) gave (1R,10R,11S,16S)-5-methoxy-1,11,15,15-tetramethyl-8-thiatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-triene (Compound No. 51) (1.10 g, 46%) as a white solid. 1H NMR (CDCl3): δ 7.19 (d, 1H), 6.58 (m, 2H), 3.72 (s, 3H), 2.95 (q, 2H), 2.40 (m, 1H), 1.84-1.35 (m, 9H), 1.20 (s, 3H), 1.18-0.99 (m, 2H), 0.95 (s, 3H), 0.85 (s, 3H), 0.82 (s, 3H). (1R,10R,11S,16S)-3-Methoxy-1,11,15,15-tetramethyl-8-thiatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-triene (Compound No. 52) (0.44 g, 19%) was also isolated as a white solid. 1H NMR (CDCl3): δ 6.96 (t, 1H), 6.67 (d, 1H), 6.56 (d, 1H), 3.78 (s, 3H), 3.32 (m, 1H), 2.82 (q, 2H), 1.82-1.40 (m, 7H), 1.38 (s, 3H), 1.35-0.98 (m, 3H), 0.92 (s, 3H), 0.95 (m, 1H), 0.87 (s, 3H), 0.83 (s, 3H).
