Benzyl Bromide → 1-Benzyl-2-((tert-butoxycarbonylamino)methyl)-5-fluoropyridinium bromide

Participants

Reaction Conditions

Reaction Steps

A mixture of benzyl bromide (4.21 mmol, 0.5 mL), tert-butyl (5-fluoropyridin-2-yl)methylcarbamate (3.49 mmol, 0.79 g) and acetone (4 mL) in a sealed tube was heated to 80° C. overnight. According to analytical HPLC, around 50% of the starting material remained. Additional benzyl bromide (33.68 mmol, 4.0 mL) was added and the reaction was continued for extra 8 h. The reaction mixture was concentrated in vacuo and loaded on a pad of silica which was rinsed with ether until benzyl bromide was gone. Then, the silica pad was rinsed with MeOH. Removal of MeOH in vacuo afforded desired product 1-benzyl-2-((tert-butoxycarbonylamino)methyl)-5-fluoropyridinium bromide as light orange solid in 43% yield. MS (ESI) 317 (M+H).

Provenance & Evidence