Ammonium Acetate → (S)-(9H-fluoren-9-yl)methyl 2-(5-(4-bromophenyl)-1H-imidazol-2-yl)-2-methylpyrrolidine-1-carboxylate

Participants

Reaction Steps

A mixture of ammonium acetate (844 mg; 10.97 mmol) and (S)-(9H-fluoren-9-yl)methyl 2-(2-(4-bromophenyl)-2-oxoethylcarbamoyl)-2-methylpyrrolidine-1-carboxylate (intermediate LS31; 1.00 g; 1.83 mmol) was heated to 140° C. in 25 mL xylene for 2.5 h at which time the reaction mixture was concentrated and loaded with dichloromethane onto a Biotage 40 samplet. Purification via Biotage (5 to 60% ethyl acetate/hexane over 1000 mL with 400 mL hold time) provided (S)-(9H-fluoren-9-yl)methyl 2-(5-(4-bromophenyl)-1H-imidazol-2-yl)-2-methylpyrrolidine-1-carboxylate (intermediate LS32; 469 mg; 49%) as an amber liquid. LC (Cond'n 12): RT=3.09 min; MS: Anal. Calcd. for [M+H]+ C29H26BrN3O2: 528.1; found 528.5.

Provenance & Evidence