Ethylenediamine → 3-Benzylpiperazin-2-one

Participants

Reaction Steps

Ethylenediamine (25 g.) is added to a stirred solution of ethyl 2-bromo-3-phenylpropionate (XXVII, Example 61, 14.0 g.) in THF (100 ml.) and ethanol (300 ml.). After 20 hours at 20°-25° the solvents are removed under reduced pressure and the residual oil is partitioned between ethyl acetate-1N sodium hydroxide solution. The ethyl acetate extract is washed with water, saline, and concentrated. The residual oil is applied to a silica gel column which is eluted with chloroform-methanol (9/1). Fractions containing the product are pooled, concentrated to a residue and recrystallized from ethyl acetate-SSB to give 3-(phenylmethyl)piperazinone, m.p. 92°-93°.

Provenance & Evidence