JD.com Inc. agreed to sell its finance arm for 14.3 billion yuan in cash while retaining a share of its future profits, part of a deal to spin off the fast-growing division and create a strong rival to billionaire Jack Ma’s Ant Financial. The sale and spinoff of JD Finance, a payments and investment business, will be completed by the middle of 2017, the Beijing-based company said Thursday without naming buyers or investors apart from Chief Executive Officer Richard Liu.