This can be achieved programmatically i.e by using Web Services Integration.
The <urn:shipToEmail>?</urn:shipToEmail> field in "createSimpleEntitlementRequest" method from the EntitlementOrderService can be used to populate the emails. Multiple emails should be comma separated.
"getUsersQueryRequest" method from the UserAcctHierarchyService can be used to fetch the users that should receive the entitlement email. You can pass the account ID that is going to be entitled,retrieve the users from this account and pass the fetched email ids to shipToEmail parameter.
In order to send emails when entitlement is being created, use the emailEntitlement web service method from EntitlementOrderService.
If you have already added recipients to your entitlement using the "urn:shipToEmail" parameter in createSimpleEntitlementRequest, then there is no need to pass emailIdList. The email addresses will be automatically fetched from "urn:shipToEmail" field.
If you have not set email recipients then you need to pass the email id of users in the emailIdList parameter of emailEntitlement method explicitly.
Thank you!
