Dimethyl Sulfoxide → 3-[3-(2-Methoxyphenylsulfonyloxy)-5-methylphenoxy]propionaldehyde

Participants

Reaction Conditions

Reaction Steps

Sulfur trioxide pyridine complex (1.87 g, 11.7 mmol) was added in portions over 15 min to a solution of 3-[3-(2-methoxyphenylsulfonyloxy)-5-methylphenoxy]propanol (2.07 g, 5.9 mmol, prepared in step c of Example 2). N,N-diisopropylethylamine (2.15 mL, 12.3 mmol), and anhydrous dimethylsulfoxide (1.25 mL, 17.6 mmol) in anhydrous dichloromethane (14 mL) at 0° C. under a nitrogen atmosphere. The solution was stirred at 0° C. for 1 h, then the reaction was quenched with 5% aqueous citric acid (50 mL). The layers were separated, and the aqueous layer was extracted with dichloromethane (15 mL). The combined organic extracts were washed with 5% aqueous citric acid (50 mL), pH 7 buffer (40 mL) and brine (50 mL), dried over Na2SO4, filtered, and evaporated. The residual gold oil was purified by flash column chromatography (3:2 diethyl ether/hexane) to give the title compound (1.28 g, 62%) as a colorless oil. 1H-NMR (300 MHz, CDCl3) δ9.82 (t, 1H, J=1.5 Hz), 7.82 (dd, 1H, J=7.9, 1.7 Hz), 7.62 (ddd, 1H, J=8.4, 7.4, 1.8 Hz), 7.09 (dd, 1H, J=8.4, 0.8 Hz), 7.02 (m, 1H), 6.58 (br s, 1H), 6.54 (br s, 1H), 6.45 (t, 1H, J=2 Hz), 4.18 (t, 2H, J=6.1 Hz), 4.02 (s, 3H), 2.85 (dt, 2H, J=6.1, 1.5 Hz), 2.24 (s, 3H). Mass spectrum (MALDI-TOF, α-cyano-4-hydroxycinnamic acid matrix) calcd. for C17H18O6S: 373.1 (M+Na). Found: 373.0.

Provenance & Evidence