Neither outgoing "Dough-Faced" Democrat President Buchanan nor incoming Republican President Lincoln ever met directly with Confederate emissaries.
Neither recognized secession as lawful or the Confederacy as legitimate.
Both believed, and Lincoln said as much in his First Inaugural, that lawful secession required the approval of Congress, and so that is where any "negotiations" had to take place.
But secessionists made no efforts to negotiate or secure approval from Congress, or for that matter to address their legal issues to the United States Supreme Court.
Instead, after rejecting constitutional methods for seceding, secessionists demanded recognition by Presidents Buchanan and Lincoln, which both refused.
No such thing.