1,1'-Carbonyldiimidazole → HCID 11062483, compound

Participants

Reaction Steps

In a 100 mL round-bottomed flask (RBF) was added carboxylic acid 1 (575 mg, 1.291 mmol) and 1,1′-carbonyldiimidazole (460 mg, 2.84 mmol) in THF (15 mL) to give a yellow solution. The mixture was stirred at room temperature under nitrogen for 1 hour then heated to 70° C., in an oil bath, for 90 minutes. The mixture was cooled and sec-butyl sulfonamide (921 mg, 6.71 mmol) in 4 mL of THF was added along with neat DBU (0.389 mL, 2.58 mmol). The RBF was returned to the oil bath and heated overnight at 70° C. The reaction mixture was transferred to a separatory funnel, diluted with 100 mL of DCM, washed ×3 with 100 mL of 0.5 M HCl, then with 100 mL of H2O, and finally saturated NaCl. The organic mixture was dried over MgSO4, filtered and concentrated to give 713 mgs of the desired acylsulfonamide 2 as a yellow solid (96% yield) which was placed under vacuum overnight. LC data was recorded on a Shimadzu LC-10AS liquid chromatograph equipped with a Phenomenex-Luna 10μ, C18, 4.6×30 mm column, using a SPD-10AV UV-Vis detector at a detector wave length of 220 nM. The elution conditions employed a flow rate of 5 ml/min., a gradient of 100% solvent A/0% solvent B to 0% solvent A/100% solvent B, a gradient time of 2 min., a hold time of 1 min., and an analysis time of 3 min. where solvent A was 10% MeOH/90% H2O/0.1% trifluoroacetic acid and solvent B was 10% H2O/90% MeOH/0.1% trifluoroacetic acid. MS data was determined using a Micromass Platform for LC in electrospray mode. 1H NMR (500 MHz, CD3OD): δ ppm 0.84-0.92 (m, 3 H), 1.03 (t, J=7.32 Hz, 3 H), 1.23 (m, 1 H), 1.28-1.44 (m, 7 H), 1.58 (m, 1 H), 1.72 (m, 2 H), 1.85 (m, 1 H), 1.95-2.07 (m, 3 H), 2.17 (m, 1 H), 2.78 (m, 1 H), 3.69 (m, 2 H), 3.83-3.91 (m, 3 H), 7.02 (s, 1 H), 7.11 (m, 1 H), 7.47 (d, J=7.63 Hz, 1 H), 7.74 (m, 3 H), 8.25 (s, 1 H). LC/MS: m/z 565.22, Rf 2.192 min., 97.5% purity.

Provenance & Evidence