1,2-Dibromoethane → 1-Methyl-4-(5-vinylpyridin-2-yl)piperazine

Temperature

95 °C

A sealed, degassed mixture of powdered KOH (123 mg, 2.2 mmol) and 1,2-dibromoethane (0.05 mL, 0.6 mmol) in anh THF (2 mL) under Ar was heated under microwave irradiation at 95° C. for 70 min. The reaction mixture was then cooled to rt and treated with Pd(OAc)2 (5.0 mg, 0.022 mmol), PPh3 (11.5 mg, 0.044 mmol), 1-methyl-4-(5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-yl)piperazine (120 mg, 0.39 mmol) and degassed MeOH (2 mL). The sealed reaction mixture was heated again under microwave irradiation at 95° C. for 60 min. The crude mixture was concentrated under reduced pressure and purified by prepTLC (SiO2 10% MeOH/DCM) to provide the title compound a colorless gum (0.18 g, quantitative): 1H NMR (400 MHz, CD3OD) δ ppm 8.07 (d, J=2.26 Hz, 1H), 7.73 (dd, J=8.91, 2.38 Hz, 1H), 6.82 (d, J=9.03 Hz, 1H), 6.62 (dd, J=17.82, 11.04 Hz, 1H), 5.63 (d, 1H), 5.12 (d, J=10.79 Hz, 4H), 3.52-3.66 (m, 4H), 2.50-2.61 (m, 4H), 2.35 (s, 3H); MS ESI 204.0 [M+H]+, calcd for [C2H17N3+H]+ 204.3.

1. customA sealed, degassed
2. temperatureThe reaction mixture was then cooled to rt
3. customdegassed MeOH (2 mL)
4. customThe sealed reaction mixture
5. temperaturewas heated again under microwave irradiation at 95° C. for 60 min
6. concentrationThe crude mixture was concentrated under reduced pressure
7. custompurified by prepTLC (SiO2 10% MeOH/DCM)

ORD record

ord-9884515c9efa4473a7e144bec423a6fd

Source dataset

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08481525B2