Reaction Steps
Piperidine (0.27 mL, 2.7 mmol) was added to a suspension of 3-methoxy-4-(naphth-2-ylmethoxy)benzaldehyde (0.80 g, 2.7 mmol) and 2-[(carboxyacetyl)amino]benzoic acid (0.55 g, 2.5 mmol) in toluene (5 mL) and treated according to Procedure 2, acidifying with 20% AcOH. The crude product was recrystallised from EtOH providing (E)-2-[[3-(3-methoxy-4-(naphth-2-ylmethoxy)phenyl)-1-oxo-2-propenyl]amino]benzoic (0.74 g, 66%) as a yellow crystalline solid; mp 197-200° C.; δH (400 MHz, DMSO-d6) 3.86 (s, 3H, OCH3), 5.30 (s, 2H, OCH2), 6.76 (d, J=15.6 Hz, 1H, CH═CHCO), 7.00 (d, J5′,6′=8.0 Hz, 1H, H5′), 7.15 (1, J3,4=J4,5=8.0 Hz, 1H, H4), 7.22 (dd, J5′,6′=8.0, J2′,6′=1.6 Hz, 1H, H6′), 7.37 (d, J2′,6′=1.6 Hz, 1H, H2′), 7.50-7.63 (m, 5H, CH═CHCO, H5, Naphth-H), 7.91-8.01 (m, 5H, H3, Naphth-H), 8.63 (d, J5,6=8.0 Hz, 1H, H6), 11.31 (s, 1H, NH), 13.59 (br s, 1H, CO2H); δC (100 MHz, DMSO-d6) 55.7, 70.1, 110.8, 113.4, 116.6, 120.1, 120.3, 122.5, 122.7, 125.9, 126.2, 126.4, 126.6, 127.6, 127.7, 127.8, 128.1, 131.2, 132.6, 132.7, 134.0, 134.5, 141.1, 141.6, 149.3, 149.6, 164.2, 169.5; HRMS (ESI) calculated for C28H23NO5 [M−H]− 452.1493. found 452.1495; vmax 1135, 1260, 1511, 1584, 1668, 3055 cm−1.
