p-Toluenesulfonic acid → HCID 902831, compound

Participants

Reaction Steps

Prepared according to general procedure using (E)-tert-butyl 3-cyclohexyl-2-(2-hydroxyphenylcarbonyl)prop-2-enoate (66 mg, 0.20 mmol), thiourea catalyst III (14 mg, 0.020 mmol) in 2.0 mL toluene for 5 d at −25° C. and p-toluenesulfonic acid (19 mg, 0.10 mmol) for 4 h. Purification via column chromatography with 10% EtOAc/hexanes afforded 30.0 mg (65%) of 16 as a white solid in 80% ee. [α]D: −53.0 (EtOH, c=0.5). Analytical data for 16: IR (film) 2928.8, 1689.6, 1608.8, 1467.1, 1310.1, 1229.6 cm−1; 1H NMR (500 MHz, CDCl3) δ 7.87 (d, J=7.3 Hz, 1H), 7.47 (t, J=7.1 Hz, 1H), 7.01-6.97 (m, 2H), 4.23-4.19 (m, 1H), 2.77-2.65 (m, 2H), 2.01-1.99 (m, 1H), 1.84-1.72 (m, 5H), 1.35-1.11 (m, 5H); 13C NMR (125 MHz, CDCl3) δ 193.4, 162.1, 136.1, 127.1, 121.2 (x2), 118.1, 82.2, 42.0, 40.4, 28.5, 28.4, 26.5, 26.15, 26.09; LRMS (electrospray): Exact mass calcd for C15H18O2 [M]+, 230.13. Found [M+1], 231.7.

Provenance & Evidence