tert-Butyl 4-(prop-2-yn-1-yl)piperazine-1-carboxylate → 1-(2-Propynyl)piperazine

tert-Butyl 4-propargylpiperazine-1-carboxylate of step 2(ii) above (570 mg, 2.545 mmol) was dissolved in trifluoroacetic acid (10 ml) and water (2.5 ml). The mixture was then stirred at room temperature overnight. The solution was evaporated to dryness in vacuum. The residue was dissolved in water (10 ml) and then basified with Na2CO3 (pH 11), and extracted with Et2OAc (3×50 ml). The organic layer was washed with brine (2×50 ml) and dried over Na2SO4 overnight. Evaporation in vacuum gave N-propargylpiperazine (D7) as white solid. (crude, 193 mg, 62% yield). H1 NMR (250 MHz, CDCl3) 1.64 (s, 1NH), 2.26 (m, 1H), 2.55 (dd, J=4.73, 4.50 Hz, 4H), 2.93 (dd, J=4.96, 4.84 Hz, 4H), 3.29 (d, J=2.44 Hz, 2H).

1. customThe solution was evaporated to dryness in vacuum
2. dissolutionThe residue was dissolved in water (10 ml)
3. extractionextracted with Et2OAc (3×50 ml)
4. washThe organic layer was washed with brine (2×50 ml)
5. dry with materialdried over Na2SO4 overnight
6. customEvaporation in vacuum

ORD record

ord-75914b66e3d946a39188902246b567bb

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08685955B2