Reaction Steps
A mixture of 3,5-diisopropyl-2-(1-hydroxyethyl)-6-pentyl-4′-fluoro-1,1′-biphenyl (Example 192, 13.7 g, 37.1 mmol), Celite (26 g), and pyridinium chlorochromate (14.9 g, 69.3 mmol) in dichloromethane (750 mL) was stirred for 45 minutes. The mixture was diluted with ethyl acetate (750 mL) and hexane (1.5 L) and filtered through a plug of silica (100 mm×2″) topped with Celite (100 mm×0.5″). Elution was continued with ethyl acetate:hexanes (1:1 mixture, 3L×2). The combined filtrates were concentrated in vacuo to afford the desired product as a white solid (13.5 g, 99%). 1H NMR (300 MHz, CDCl3): δ 0.75-0.80 (m, 3H), 1.06-1.31 (m, 18H), 1.95 (s, 3H), 2.33-2.39 (m, 2H), 2.78 (septet, J=7.0 Hz, 1H), 3.18 (septet, J=7.0 Hz, 1H), 7.03-7.09 (m, 2H), 7.17-7.22 (m, 2H) 7.26 (s, 1H). 13C NMR (75 MHz, CDCl3): δ 13.75, 22.02, 24.32, 24.37, 28.99, 29.10, 29.28, 30.60, 31.04, 32.06, 33.03, 114.85 (d, J=20.8 Hz, 2C), 122.06, 132.03 (d, J=7.3 Hz, 2C), 135.52 (d, J=2.4 Hz, 1C) 135.58, 135.76, 140.13, 140.85, 147.66 161.99 (d, J=246.6 Hz, 1C), 208.23. EI-MS: calculated for C25H33OF 368; found 368 (M+). Anal. calc for C25H33OF: C, 80.86; H, 8.96. Found: C, 81.04; H, 9.06. Rf=0.65 (9:1 hexanes:ethyl acetate). HPLC: (C-18, A=0.05% aqueous trifluoroacetic add, B=CH3CN; linear gradient: 75%-100% B over 30 min; 254 nm, 1 mL/min): R.T. 22.7 min (94.0 area %). mp 123.0-124.5° C.
