A division of property at the time of the divorce is not taxable or deductible. But ongoing payments would probably be characterized as alimony or support, even if they were directed to be paid to an IRA rather than directly to the ex-spouse. In that case, they fall under the alimony rules and the answer is "no" if the divorce was filed after Jan 1, 2019, and "maybe" if the divorce was filed before Dec 31, 2018. But it will never be deductible in the IRA section, because it's not your IRA. It is either deductible as alimony or not deductible at all.
