2,6-Diisopropyl-4-(4-fluorophenyl)-5-pentyl-3-pyridine-carboxaldehyde → 2,6-Diisopropyl-3-ethenyl-4-(4-fluorophenyl)-5pentylpyridine

Participants

Reaction Conditions

Reaction Steps

Methyl triphenylphosphonium bromide was suspended in 15 mL of dry THF under argon and stirred at −78° C. Butyllithium (1.6M, 0.42 mL) was added dropwise over 2 min. and then the reaction mixture was allowed to stir at 0° C. for 1.5 hours. The solution was cooled again to −78° C., treated dropwise with a solution of 2,6-diisopropyl-4-(4-fluorophenyl)-5-pentyl-3-pyridinecarboxaldehyde (Example 114, Step A) in 5 mL of dry THF, and then stirred at 0° C. for 2.5 hours. The reaction was quenched with water (10 mL) and the THF evaporated in vacuo. Diethyl ether was added and the mixture was washed with water (2×20 mL), brine (1×20 mL), and dried with MgSO4. Filtration, concentration and flash chromatography (30% CH2Cl2/hexanes) yielded a solid (0.132 g, 0.37 mmol, 66%). 1H NMR (300 MHz, CDCl3) δ 7.08 (m, J=1.1 Hz, 4 H), 6.34, 6.28 (d, J=11.4 Hz, J=11.4 Hz, 1 H), 5.19 (d, J=1.8 Hz, 1 H), 4.96 (d, J=1.8 Hz, 1 H), 3.39 (septet, J=6.6 Hz, 1 H), 3.24 (septet, J=6.6 Hz, 1 H), 2.30 (t, J=5.2 Hz, 2 H), 1.20 (m, J=2.2 Hz, 18 H), 0.979 (t, J=6.0 Hz, 3 H). FAB-MS: calcd for (C24H32FN) 353, found 354 (M+H). Anal. Calcd for C24H32FN: C, 81.54; H, 9.12; N, 3.96; F, 5.37. Found: C, 81.46; H, 9.06; N, 3.78; F, 5.59. mp 44-46° C. Rf=0.7 (30% CH2Cl2/hexanes).

Provenance & Evidence