反応手順
The alcohol (3.2 g) was stirred with manganese (IV) oxide (10 g) in CH2Cl2 (100 ml) at RT for 3 h. The mixture was filtered through Celite® and the filtrate concentrated in vacuo. The residual dark oil was subjected to chromatography (SiO2) to give (3-cyclopentyloxy-4-methoxyphenyl)-(2-furyl)ketone (1.9 g); vmax (neat) 1620cm-1. n-Butyllithium (1.6M solution in hexanes; 4.2 ml, 6.64 mmol) was added to a solution of a 4-methylpyridine (0.62 g, 0.65 ml, 6.64 mmol) in THF (25 ml) at -70° C. After 0.5 h, a solution of the crude ketone (1.9 g, ca 6.6 mmol) in THF (5 ml) was added, stirred for 1 h at -70° C., then at RT fix 0.25 h. The reaction mixture was quenched with water (50 ml) and extracted with EtOAc (3×50 ml). The extract was dried (MgSO4), concentrated in vacuo, and the residual red oil subjected to chromatography (SiO2 ; EtOAc/hexane, 3:2) to afford the title compound (1.23 g, 49%) as a pale yellow oil; δH (CDCl3) 1.5-1.9 (8H, br m, (CH2)4), 2.84 (1H, br s, OH), 3.30 (1H, d, J 13.2 Hz, CHAHB pyridine), 3,59 (1H, d, J 13.2 Hz, CHAHB pyridine), 3.82 (3H, s, OMe), 4.65 (1H, br m OCH), 6.24 (1H-[, dd, J 3.3, 0.7Hz, furan H3), 6.35 (1H, dd, J 3.3, 1.8Hz, furan H4), 6.75-6.85 (3H, m, C6H3), 6.85 (2H, dd, J 4.5, 1.6Hz, pyridine H3,H5), 7.43 (1H, dd, J 1.8, 0.7Hz, furan H5), and 8.33 (2H, dd, J 4.5, 1.6Hz, pyridine H2, H6); m/z (ESI) 402 (M+ +23, 20%), 380 (M+ +1, 35), 287 (100), 95 (28), and 94 (97).
