Oxalyl chloride → Hydrazinecarboxylic acid, 2-[2-[2-(3-buten-1-yloxy)phenyl]acetyl]-, 1,1-dimethylethyl ester

Participants

Reaction Steps

To a solution of 2-(2-(but-3-en-1-yloxy)phenyl)acetic acid (0.22 g, 1.06 mmol, 1 equiv) in DCM (11 mL) was added one drop DMF followed by oxalyl chloride (0.19 mL, 2.11 mmol, 2 equiv). Gas evolution observed. After 1 h, the reaction was concentrated in vacuo to provide the crude acid chloride. The acid chloride was taken up in DCM (5 mL) and added slowly to a solution of tert-butyl hydrazinecarboxylate (168 mg, 1.27 mmol, 1.2 equiv) and DIPEA (0.55 mL, 3.17 mmol, 3 equiv) in DCM (11 mL). After stirring 1 h, the reaction was diluted with DCM, washed with saturated aqueous NaHCO3, dried (MgSO4), and concentrated in vacuo. The crude product was purified via flash column chromatography (0-100% EtOAc/hexane) to provide the product (0.28 g, 83%) as a viscous tan oil. 1H NMR (400 MHz, CDCl3) δ 7.62 (br. s., 1H), 7.31-7.23 (m, 2H), 7.00-6.87 (m, 2H), 6.48-6.26 (m, 1H), 5.99-5.85 (m, 1H), 5.23 (dd, J=17.1, 1.5 Hz, 1H), 5.17 (d, J=10.3 Hz, 1H), 4.14-4.09 (m, 2H), 3.61 (s, 2H), 2.61 (q, J=6.4 Hz, 2H), 1.48-1.36 (m, 9H).

Provenance & Evidence