Reaction Steps
Potassium t-butoxide (30.32 g, 97%, 0.262 mol.) was added to a solution of p-N,N-Bis(2-t-butyldimethylsiloxyethyl)aminobenzaldehyde (, 53.4 g, 0.122 mol.) and 2-hexyl-isophorone (compound 10, 26.6 g, 0.118 mol.) in diglyme (200 mL, KOH dried) over 3 min. Ice bath was used to keep the temperature below 50° C. The reaction mixture was stirred at room temperature for 25 min. and then was poured to dilute acetic acid (0.28 mol HOAc in 200 mL of water). The extra acid was neutralized with saturated aqueous sodium bicarbonate. The organic layer was separated, washed with water, dried with magnesium sulfate and rotovapped to dryness. The residue was purified by a silica gel column using ethyl acetate/hexane (1/20, v/v) to afford 8.33 g red thick oil: yield 22% based on reacted starting material. 1H NMR (CDCl3) : δ7.36 (d, 8.81 Hz, 2H), 7.14 (d, 16.06 Hz, 1H), 6.88 (d, 16.09 Hz, 1H), 6.69 (d, 8.91 Hz, 2H), 3.78 (t, 6.06 Hz, 4H), 3.56 (t, 5.89 Hz, 4H), 2.53 (br, 2H), 2.48 (s, 2H), 2.29 (s, 2H), 1.33 (m, 8H), 1.05 (s, 6H), 0.90 (s, 18H), 0.04 (s, 12H) ppm. 13C NMR (CDCl3): δ198.87, 148.41, 147.67, 134.47, 134.19, 128.52, 124.38, 121.71, 111.54, 60.21, 53.42, 51.37, 39.82, 32.27, 31.65, 29.90, 29.37, 28.39, 25.79, 24.30, 22.54 ppm.
