Oxygen → Methyl 3-(3,5-dimethoxyphenyl)-2-[4-[4-[(2,4-dioxo-1,3-thiazolidin-5-yl)methyl]phenoxy]phenyl]prop-2-enoate

Participants

Reaction Conditions

Reaction Steps

To a solution of 10 (599 g, 1.16 mol) in glacial acetic acid (11.5 L), ammonium formate (4.0 kg, 62.9 mol) was added and stirred for 30 min. A slurry of Pd on carbon (10%, dry, 300 g) in glacial acetic acid (500 mL) was added to the flask (caution: in a large scale reaction exothermicity may be a problem; rigorous exclusion of oxygen is desirable) and heated at 120° C. for 24 h followed by stirring at room temperature for 48 h. The resulting mixture was filtered through a bed of Celite®. The filtrate was poured slowly into vigorously stirred water (12 L) and the separated solid was filtered and dried. Resulting solid was purified by slurring twice in hot methanol followed by once from ethanol to yield pure 11 as white solid (296 g, 49.2%): mp 126-128° C.; 1H NMR (400 MHz, DMSO-d6) δ 12.01 (br s, 1H), 7.73 (s, 1H), 7.28 (d, J=8.6 Hz, 2H), 7.19 (d, J=8.6 Hz, 2H), 7.02 (d, J=8.6 Hz, 2H), 6.96 (d, J=8.6 Hz, 2H), 6.40 (t, J=2.2 Hz, 1H), 6.27 (d, J=2.2 Hz, 2H), 4.92 (dd, J=9.2 and 4.4 Hz, 1H), 3.73 (s, 3H), 3.57 (s, 6H), 3.37 (dd, J=14.8 and 4.3 Hz, 1H) and 3.12 (dd, J=14.8 and 9.4 Hz, 1H); IR (KBr) νmax 3200, 2950, 2850, 1700, 1600, 1500, 1350, 1150, and 850 cm−1; MS (EI) m/z 518[M-H]−, 265, 249, and 113; Anal. (C28H25NO7S) C, H, N.

Provenance & Evidence