Benzene → Methyl 2-methoxy-5-{1-[4-methoxy-3-(methoxycarbonyl)phenyl]hept-1-en-1-yl}benzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

n-Hexyltriphenylphosphonium bromide (0.427 g, 1 mmol) was dried by azeotropic distillation from a benzene solution and then stirred in dry THF (10 mL) under nitrogen atmosphere. Sodium bis(trimethylsilyl)amide (1 M in THF, 1 mL, 1 mmol) was added and the ylide produced was stirred under nitrogen at 0° C. for 30 min. Intermediate 35 (0.276 g, 0.77 mmol) was added as a solution in THF (10 mL) under nitrogen. The mixture was stirred at rt overnight and partitioned between 1 N HCl (100 mL) and ethyl acetate (100 mL). The organic layer was dried over sodium sulfate, and evaporated to afford an oil which was chromatographed on SiO2 (230-400 mesh, 50 g), eluting with hexanes/ethyl acetate (4:1) to give the product (36) (0.15 g, 46%) as an oil: 1H NMR (CDCl3, 300 MHz) δ 7.63 (d, J=2.3 Hz, 1H), 7.56 (d, J=2.2 Hz, 1H), 7.20 (dt, J=2.3 Hz, 1H), 6.94 (d, J=8.6 Hz, 1H), 6.82 (d, J=8.7H, 1H), 5.96 (t, J=7.5 Hz, 1H), 3.90 (s, 3H), 3.84 (s, 3H), 3.83 (s, 6H), 2.05 (q, J=7.3 Hz, 2H), 1.39 (t, J=7.2 Hz, 2H), 1.22 (m, J=1.9 Hz, 2H), 0.83 (t, J=6.7 Hz, 3H); IR (neat) 2927, 2853, 1732, 1606, 1500, 1435, 1263 cm−1. Anal. (C25H30O6) C, H.

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