Leave request in ESS

Hi  Experts,

As per our custom requirement for certain set of absence type they want the below logic

1. When employee submit leave, even manager is not approved i.e. Leave request in SENT stauts Quota should deducted in IT2006
2. Once the leave is approved a record should be created in IT2001
3. If approver rejects the leave request then the deduction made to quota should be reversed.

Kindly let me know if there any way to achive this also the fm or bapi to be used to deduct/reverse deduction of IT2006.

Could you please advise.

Thanks,

Anju