We also sought TCN-NBnsyn for comparison of its anti-diastereomer (Figure ). While TCN-NBnsyn and TCN-NBnanti may potentially be separable by chromatography, we identified a kinetic resolution method that leveraged the large difference in imidation rates between the syn (slow) and anti (fast) amic acids formed upon initial ring-opening opening of 1, ultimately giving TCN-NBnsyn in 4% yield over 2 steps with >98:2 d.r. (Supporting Information Section 2). The relative configurations of TCN-NBnsyn and TCN-NBnanti were unambiguously determined by single-crystal X-ray diffraction (Figure ). TCND derivatives TCND-(CO2Me)2 and TCND-