You cannot use DSCC to perform this task. Use the command line, as described in this procedure.
Create a new dynamic group by using the ldapmodify command.
For example, to create a new dynamic group called “3rd Floor”, which includes all employees whose room numbers start with 3, you could use this command:
$ ldapmodify -a -h host1 -p 1389 -D cn=admin,cn=Administrators,cn=config -w - dn: cn=3rd Floor, ou=Groups, dc=example,dc=com changetype: add cn: 3rd Floor objectclass: top objectclass: groupOfUrls ou: Groups memberURL: ldap:///dc=example,dc=com??sub?(roomnumber=3*)