反应详情

1,1-Dimethylethyl 4-[3-(methyloxy)-4-nitrophenyl]-1-piperazinecarboxylate (combined batches) (5.16 g, 15.3 mmol) in DCM was cooled with an ice/H2O bath and TFA (30.0 mL, 398 mmol) was added dropwise via an addition funnel. Upon completion by TLC, the reaction was quenched slowly with 1N NaOH until the aqueous layer was basic as determined by pH paper. The mixture was extracted with DCM, dried (MgSO4) and concentrated to provide the title compound of step B (3.52 g, 14.9 mmol, 97%). 1H NMR (400 MHz, DMSO-d6) δ ppm 2.34 (br. s., 1H), 2.73-2.77 (m, 4H), 3.26-3.33 (m, 4H), 3.85 (s, 3H), 6.45 (d, J=2.4 Hz, 1H), 6.52 (dd, J=9.4, 2.5 Hz, 1H), 7.83 (d, J=9.3 Hz, 1H).

1. customUpon completion by TLC, the reaction was quenched slowly with 1N NaOH until the aqueous layer
2. extractionThe mixture was extracted with DCM
3. dry with materialdried (MgSO4)
4. concentrationconcentrated