Maybe I don't get smething, but if there is no link, you just shouldn't use an <a /> element in the first place. Use some <span /> or attach event listeners to list elements. You can style these elements to have cursor: pointer; using CSS.
Remember that browsers have some special actions associated with links, like "open in new tab", "save target element" etc. When you use dummy href='' attribute these actions work in a broken way, so it's better to not use links at all.
On the other hand, if you are able to render content of these ajaxified parts as normal pages (and it makes sense), follow nickf's advice.
