What kind of coupon? A coupon that requires you to use a Kohl's charge? No. A regular coupon valid with any payment type? Yes.
This is not true as stated by many others. As long as you charge "something" to your card you can use a Kohl's Charge Card coupon even if paying primarily with a gift card.
According to my relative that works at Kohls, they are not supposed to allow that. The full amount is supposed to go on the Kohls Charge. So you may get lucky or you may be told you have to charge the full amount.