Dimethylformamide → 4,5-Dihydro-6-oxa-1-thia-3-aza-benzo[e]azulene-2-carboxylic acid (2-chloro-phenyl)-methyl-amide

Participants

Reaction Steps

To a suspension of 4,5-dihydro-6-oxa-1-thia-3-aza-benzo[e]azulene-2-carboxylic acid (1 eq, 0.38 mmol, 101 mg) in anhydrous DCM (3 ml), I drop of DMF was added, followed by 2M oxalyl chloride in DCM (1.7 eq, 0.65 mmol, 330 ul) dropwise. Effervescence was seen and the reaction was stirred at room temperature for 40 mins before evaporating in vacuo. The crude material was dissolved in DCM (3 ml) and 2-chloro-N-methyl aniline (2 eq, 0.76 mmol, 94 ul) was added. The reaction was stirred at room temperature for 16 hr and extracted into DCM, washed with aq K2CO3, the organic layer dried over MgSO4, filtered, and purified on silica (ISCO, gradient 0% ethyl acetate/petrol to 25% ethyl acetate/petrol) to give 326 as a white solid (42 mg, yield 30%). 1H NMR DMSO, 2.89-2.92 (2H, m), 3.43 (3H, s), 4.23 (2H, br. m), 7.02 (1H, d, J=8.4), 7.08 (1H, t, J=7.6), 7.26 (1H, t, J=8), 7.38-7.41 (2H, m), 7.48-7.51 (2H, m), 7.58 (1H, d, J=8.4). MS: (ESI+): MH+ 371, purity >95%.

Provenance & Evidence