Methyl iodide → Tert-butyl 4-methyl-3-oxopiperazine-1-carboxylate

Participants

Reaction Steps

1-tert-Butoxycarbonyl-3-oxopiperazine (see Tetrahedron Lett. (1980), 21(32), 3019-20 for outline of synthesis, 5 g) was dissolved in dry DMF (75 ml) and potassium tert-butoxide (3.08 g) was added. The mixture was stirred at ambient temperature for 1 hour, then iodomethane (3.9 g) was added, and stirring continued at the same temperature for 2.5 hours. Solvent was evaporated, and the residue chromatographed on silica, using as eluant a gradient increasing in polarity from 0 to 100% ethyl acetate in iso-hexane. Relevant fractions were combined and evaporated to give 1-tert-butoxycarbonyl-4-methyl-3-oxopiperazine (3.92 g).

Provenance & Evidence