Three 7-methyl-1, 4-dioxa-7-azaspiro [4.5] decanea that contained either the benzyl, 3- indolylmethyl, or Cindolylmethyl group at the 6-position were synthesized via alkylation of the pyrrolidine enamine of the key intermediate, ethyl 3-oxopiperidine-l-carboxylate. The