Dimethylformamide → 5-(2,4-Bis-benzyloxy-5-chloro-phenyl)-4-(4-formyl-phenyl)-isoxazole-3-carboxylic acid ethylamide

Participants

Reaction Conditions

Reaction Steps

5-(2,4-Bis-benzyloxy-5-chloro-phenyl)-4-iodo-isoxazole-3-carboxylic acid ethylamide (prepared as for Example 31) (2 g, 3.4 mmol), 4-formylboronic acid (0.612 g, 4.08 mmol), NaHCO3 (10.2 ml, 1M aq. solution, 10.2 mmol), PdCl2(PPh3)2 (119 mg, 0.17 mmol) and DMF (50 ml) were combined. The mixture was then degassed by bubbling N2 through it for 5 minutes before being heated at 80° C. for 1 hour. The mixture was then evaporated in vacuo and partitioned between EtOAc (3×50 ml) and water (50 ml). The combined, dried (Na2SO4) organics were evaporated in vacuo to give a crude oil. This was dissolved in EtOAc and passed through a plug of SiO2, washing through with EtOAc. The filtrate was evaporated in vacuo and the resulting oil triturated with Et2O to afford 5-(2,4-Bis-benzyloxy-5-chloro-phenyl)-4-(4-formyl-phenyl)-isoxazole-3-carboxylic acid ethylamide (1.577 g, 82%) as a pale coloured solid, LC/MS: RT=2.908 min. 567.3 (MH+).

Provenance & Evidence