Triethylamine → tert-Butyl 4-cyanopiperazine-1-carboxylate

1,1-Dimethylethyl 1-piperazinecarboxylate (25 g, 134.2 mmol) was taken into THF (100 mL) followed by addition of triethylamine (25 mL, 178 mmol). The solution was cooled to 0° C. followed by addition dropwise addition of cyanogen bromide (15.6 g, 147.6 mmol) in THF (100 mL) and the resulting mixture was allowed to warm to room temperature then stirred an additional 12 hours. The reaction mixture was concentrated in vacuo and partitioned with ethyl ether and water. The organic layer was washed once with saturated aqueous NaCl then dried over anhydrous magnesium sulfate followed by concentration to afford 1,1-dimethylethyl 4-cyanopiperazine-1-carboxylate (24.5 g, 86% yield) as a colorless crystalline solid. 1H-NMR (400 MHz, CDCl3): 3.51 (tr, 4H), 3.19 (tr, 4H), 1.46 (s, 9H).

1. temperatureto warm to room temperature
2. concentrationThe reaction mixture was concentrated in vacuo
3. custompartitioned with ethyl ether and water
4. washThe organic layer was washed once with saturated aqueous NaCl
5. dry with materialthen dried over anhydrous magnesium sulfate
6. concentrationfollowed by concentration

ORD record

ord-adeb128d13d043d7a0b3435381e8c091

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08658654B2