Chemical Properties
White to off-white solid
Uses
4-Boc-2-oxopiperazine is used in the synthesis of renin inhibitors. Also used in the synthesis of isoindoline inhibitors of dipeptidyl peptidases.
Synthesis
GENERAL STEPS: Piperazin-2-one (1.037 g, 10.4 mmol) was dissolved in 52 mL of dichloromethane, followed by the addition of di-tert-butyl dicarbonate (Boc2O, 2.5 g, 11.4 mmol). The reaction mixture was stirred at room temperature for 3 h before complete consumption of piperazin-2-one was confirmed by thin layer chromatography (TLC) monitoring. Upon completion of the reaction, the reaction mixture was diluted with dichloromethane and the organic layer was washed with deionized water. The organic layer was separated, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to afford 1-Boc-3-piperazinone (product 33) in quantitative yield as a white solid. The structure of the product was confirmed by 1H NMR (300 MHz, CDCl3): δ 1.48 (s, 9H), 3.35-3.44 (m, 2H), 3.64 (t, J = 5 Hz, 2H), 4.10 (s, 2H), 6.41 (br s, 1H).
References
[1] Patent: WO2005/117904, 2005, A2. Location in patent: Page/Page column 407
[2] Patent: WO2011/41713, 2011, A2. Location in patent: Page/Page column 147-148
[3] European Journal of Medicinal Chemistry, 2015, vol. 101, p. 218 - 235
[4] Patent: WO2006/72350, 2006, A1. Location in patent: Page/Page column 37
[5] Patent: WO2006/72353, 2006, A1. Location in patent: Page/Page column 30
