This is for a S corp in which the owner is the employee.  

The owner/employee has a $20 gift card/coupon to a store.  The S. Corp is going to incur a business expense at that same store for an item that would be 100% deductible.  If during check out, the tax payer uses that gift card, could then the S. Corp reimburse the owner for that $20?  By doing so, the S corp gets the full deduction.   So if the expense was $100, the S corp pays $80 at the store, and reimburses $20 to the owner/employee, and writes off the full $100.

My opinion that is fine as that is almost like the $20 was just cash the owner used to which would have been reimbursable to the corporation.

Thanks!