Ammonium Acetate → Ethyl (5R)-2-amino-5-methyl-1-cyclopentene-1-carboxylate

Participants

Reaction Steps

Ammonium acetate (240 g, 3110 mmol) was added to a solution of (R)-ethyl 2-methyl-5-oxocyclopentanecarboxylate (106 g, 623 mmol) in MeOH (1.2 L). The reaction mixture was stirred at room temperature under nitrogen for 20 hours, after which it was complete as determined by TLC and HPLC. The reaction mixture was concentrated to remove MeOH. The resulting residue was dissolved in DCM, washed twice with H2O, once with brine, dried (Na2SO4), filtered, and concentrated to give (R)-ethyl 2-amino-5-methylcyclopent-1-enecarboxylate (102 g, 97% yield) as an oil. LC/MS (APCI+) m/z 170 [M+H]+.

Provenance & Evidence