Benzamide → Alpha-Hydroxyhippuric acid

Participants

Reaction Steps

The titled compound 65 was prepared according to a procedure described by Zoller et al.209 A mixture of benzamide 35 (5.00 g, 41.3 mmol) and glyoxylic acid monohydrate 41 (4.32 g, 46.9 mmol) in anhydrous acetone (70 mL) was heated at reflux for 19 h. The reaction mixture was evaporated under reduced pressure to afford the desired product 65 as a colourless solid (8.06 g, 100%), m.p. 198-200° C. (lit.209 200-201° C. (dec)) Spectroscopic data indicated the crude product 65 did not require purification and was used directly in the subsequent reaction (Section 7.11.4). νmax (KBr): 3310 bs, 3058 w, 1728 s, 1646 s, 1602 w, 1582 w, 1535 s, 1491 w, 1452 w, 1315 m, 1292 w, 1254 m, 1161 m, 1097 s, 1040 m, 1002 w, 957 m, 805 w, 770 w, 728 m, 692 m, 654 m, 609 w, 515 m, 483 w cm−1. 1H n.m.r. (300 MHz, D6-DMSO): δ 5.60 (d, J=7.8 Hz, 1H, H2), 7.41-7.49 (m, 2H, H3′, 5′), 7.55 (m, 1H, H4′), 7.86-7.92 (m, 2H, H2′, 6′), 9.26 (d, J=7.8 Hz, 1H, NH), two exchangeable OH protons not observed. 13C n.m.r. (75 MHz, D6-DMSO): δ 71.7 (C2), 127.6, 128.3, 131.7 (Arom CH), 133.7 (C1′), 166.0, 171.5 (C1, CONH). Mass Spectrum (ESI+, MeOH): m/z 218.2 (M+Na)+, C9H9NNaO4 requires 218.2.

Provenance & Evidence