tert-Butanol → butyl (E) 3-(4-iodophenyl)-but-2-enoate

Beteiligte Stoffe

Reaktionsschritte

A solution of tert-butyl diethylphosphonoacetate (10.0 g, 39.6 mmol) in 30 mL of dry THF was added slowly to a freshly prepared solution of 19 mL of 2.5 M (hexanes) lithium tert-butoxide and tBuOH (30 mL) and stirred for 1 h. A solution of 4-iodoacetophenone (1b) (9.0 g, 36.6 mmol) in 20 mL of dry THF was added to the reaction mixture and stirring was continued overnight. The solvents were removed under vacuum. The residue was dissolved in 400 mL of Et2O and was washed with water (2×30 mL) followed by brine (30 mL) and dried over MgSO4. After filtration and evaporation of the solvent, the crude product was then purified by silica gel column chromatography, eluting with 1% EtOAc in hexane. The product 2b was obtained as an oil (10.0 g, 79% yield). 1HNMR (CDCl3, 300 MHz) δ 1.515 (s, 9H), 2.48 (s, 3H), 6.03 (s, 1H), 7.18 (d, 2H, J=8.4 Hz), 7.68 (d, 2H, J=8.4 Hz). 13C NMR (CDCl3, 75.0 MHz) δ 17.5, 28.3, 80.2, 94.6, 119.5, 128.0, 137.6, 141.9, 152.6, 166.1. Anal. Calcd. for C14H17IO2: C, 48.85; H, 4.98; I, 36.87; 0, 9.3 : Found C, 49.40; H, 5.00, I, 35.97. HRMS (M+H) calc, 345.0351; found, 345.0319.

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