Reduction of 2-diphenylmethylenesuccinimide with sodium borohydride in a mixture of tetrahydrofurane-ethanol afforded 3-diphenylmethylene-5-ethoxy-2-pyrrolidinone which was readily converted to 5-(1-pyrrolidinyl)-, 5-(1-piperidinyl)-, and 5-(4-morpholinyl)-3-diphenylmethylene-2-pyrrolidinone in good yields.
