SQL & PL/SQL

I can't fix this very simple sql which executed well before I tried to wrap it in "EXECUTE IMMEDIATE". Error is as follows (Yes I understand single quotes need to be replaced with double single-quotes, this is why I cut down stored proc body to as simple as below for debugging purpose):

BEGIN IMMEDIATE 'CREATE OR REPLACE PROCEDURE spDeleteAccessToken; END;
Error at line 1
ORA-01756: quoted string not properly terminated
Script Terminated on line 1.

It didn't really help me telling me "line 1 not properly terminated". Procedure as follows.

EXECUTE IMMEDIATE 'CREATE OR REPLACE PROCEDURE spDelete
*(*
OwnerId number,
OwnerClassifier varchar2,
NumTokensDeleted OUT int
*)*
AS
bOwnerSpecified boolean := false;
Begin
NumTokensDeleted := 0;
End;';

Thanks