2-Methylpyrrolidine → 1-[2-(6-Bromo-naphthalen-2-yl)-ethyl]-2-methyl-pyrrolidine

Participants

Reaction Conditions

Reaction Steps

To a cooled solution of 2-methylpyrrolidine (2.0 mL, 20 mmol) in THF (30 mL) at −15° C. was added n-BuLi (1.6 M in hexane, 4.0 mL, 6.4 mmol) dropwise keeping the temperature below −10° C. The resulting mixture was stirred at −15° C. for 10 min. To the cooled solution was added a solution of 2-bromo-6-vinyl-naphthalene (3) (2.33 g, 10.0 mmol) in THF (30 mL) dropwise keeping the temperature below −15° C. The resulting mixture was stirred at −15° C. for 5 min. and quenched with H2O (1 mL) and then poured into 5% Na2CO3 (80 mL). To the mixture was added EtOAc (80 mL), and organic was separated, the aqueous layer was extracted with EtOAc (30 mL). The combined organic layer was washed with brine and treated with activated carbon, dried over Na2SO4 and concentrated. The residue was then further dried under high vacuum to give 2.47 g product. The crude product was used in the next step without further purification. 1H NMR (400 MHz, CDCl3) d 7.86 (d, 1H), 7.53–7.59 (m, 3H), 7.40–7.42 (dd,1H), 7.28–7.30 (dd, 1H), 3.04–3.22 (m, 1H), 3.98–3.04 (m, 1H), 2.85–2.91 (m, 2H), 2.23–2.33 (m, 2H), 2.14 (q, 1H), 1.81–1.88 (m, 1H), 1.62–1.78 (m, 2H), 1.32–1.39 (m, 1H), 1.04 (d, 3H). 13C NMR (400 MHz, CDCl3) d 138.50, 132.75, 131.65, 129.29, 128.90, 128.76, 128.21, 126.63, 126.34, 118.72, 60.11, 55.88, 54.15, 35.78, 32.93, 21.98, 19.28. [M+H]+ at m/z 319.

Provenance & Evidence