trans-2-Phenyl-1-cyclopropanecarbonyl chloride → trans-(4-Cyclobutylpiperazin-1-yl)-(2-phenylcyclopropyl)methanone

Participants

Reaction Steps

To a stirring slurry of 4A (130 mg, 0.610 mmol) in anhydrous DCM (3.5 mL) under an argon (g) atmosphere was added TEA (0.162 mL, 1.16 mmol). After 1 min. trans-2-phenyl-1-cyclopropanecarbonyl chloride (0.096 mL, 0.55 mmol) was added in one portion to the now clear solution. The reaction was left to stir for ca. 1.5 h at ambient temperature before being washed with H2O (2×2 mL), dilute aq. K2CO3 (1×2 mL), H2O (1×2 mL), dried over MgSO4, filtered and concentrated in vacuo. The resulting gum was subjected to flash chromatography (basic alumina-8 g; gradient elution: 5% EtOAc/Hexane for 1 min. then 5-55% EtOAc/Hexane over 7 min. at 18 mL/min) to afford 90 mg 4B as a white solid (57% yield). m/z (ES+) M+1=285.2; HPLC tR=1.54 min. 1H NMR (500 MHz, CDCl3) δ 7.29-7.24 (m, 2H), 7.20-7.16 (m, 1H), 7.10 (d, J=7.0 Hz, 2H), 3.80-3.46 (m, 4H), 2.72 (quintet, J=7.9 Hz, 1H), 2.47 (ddd, J=9.0, 6.3, 4.0 Hz, 1H), 2.39-2.25 (m, 4H), 2.08-1.98 (m, 2H), 1.95 (td, J=4.4, 3.7 Hz, 1H), 1.92-1.81 (m, 2H), 1.78-1.59 (m, 3H), 1.27-1.24 (m, 1H).

Provenance & Evidence