Ah, the joys of credit cards. They play havoc with the IRS notions of "accrued" accounting versus "cash".
But generally speaking, business expenses are tied to their receipts. The IRS presumes that you accepted responsibility for paying the item on the day your card was swiped at the register. The only thing that your business is allowed to deduct later is the interest you're paying the credit card company. I've not yet seen the IRS try to tie credit card *payments* to the tax year, they are always only looking for the date the transactions posted to the card.


