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

Participants

Reaction Conditions

Reaction Steps

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, 1 H), 7.73 (dd, J=8.91, 2.38 Hz, 1 H), 6.82 (d, J=9.03 Hz, 1 H), 6.62 (dd, J=17.82, 11.04 Hz, 1 H), 5.63 (d, 1 H), 5.12 (d, J=10.79 Hz, 4 H), 3.52-3.66 (m, 4 H), 2.50-2.61 (m, 4 H), 2.35 (s, 3H); MS ESI 204.0 [M+H]+, calcd for [C12H17N3+H]+ 204.3.

Provenance & Evidence