A good complement is the 1994 A Critical and Exegetical Commentary on the Second Epistle to the Corinthians, Vol. 1... it's on 2 Cor 1-7.For example 2 Cor 5:18.The Hermeneia-set has a commentary on chapters 8-9.According to the end-of-2011 Oxford Encyclopedia of the Books of the Bible and Christian Origins by Jonathan Knight, Continuum 2008 the remaining chapters of 2 Cor are secondary literature.
Thanks, Unix!