High fidelity sorting of remarkably similar components via metal-mediated assembly† †Electronic supplementary information (ESI) available: See DOI: 10.1039/c5sc01689d Click here for additional data file.

Subtle differences in coordination angle and rigidity lead to narcissistic self-sorting between highly similar individual components upon metal-mediated assembly.

1 H and 13 C NMR spectra were recorded on a Varian Inova 400 MHz or Varian Inova 500 MHz NMR spectrometer. DOSY spectra were recorded on a Bruker Avance 600 MHz spectrometer. Proton ( 1 H) chemical shifts are reported in parts per million () with respect to tetramethylsilane (TMS, =0), and referenced internally with respect to the protio solvent impurity. Deuterated NMR solvents were obtained from Cambridge Isotope Laboratories, Inc., Andover, MA, and used without further purification. Mass spectra were recorded on an Agilent 6210 LC TOF mass spectrometer using electrospray ionization with fragmentation voltage set at 115v and processed with an Agilent MassHunter Operating System. All other materials were obtained from Aldrich Chemical Company, St.
Louis, MO, or TCI, Tokyo, Japan and were used as received. Solvents were dried through a commercial solvent purification system (Pure Process Technologies, Inc.). The synthesis and characterization of ligands A and B, as well as complexes 1 and 2, are described in our previous report. 1 X-ray crystallographic data for homocomplexes 1 (CCDC # 951758) and 2 (CCDC # 951759) can be found in our previous report. 1 The minimized structures of cages 3-5 were obtained via density functional calculations, and were optimized using the dispersion-corrected B97-D density functional 2,3 in the 6-31G(d) basis set. 4

3,7-Dinitrodibenzosuberenone (S-1):
3,7-Dinitrodibenzosuberone (100 mg, 0.33 mmol) was added to a 50 mL round bottom flask with stir bar, followed by the addition of benzene (25 mL). 1.1 equivalents N-bromosuccinimide (64.8 mg, 0.36 mmol) was slowly added to the flask, followed by 0.1 eq benzoyl peroxide (8.0 mg, 0.03 mmol). The reaction mixture was refluxed for 12 h, after which the solid was filtered and dried. The crude solid was placed into a 50mL round bottom flask followed by acetone (25 mL). Potassium iodide (60.4 mg, 0.33mmol) was added to the flask and the mixture was stirred at room temperature for 4 h. The reaction mixture was then filtered and the product collected as a light yellow solid (47 mg, 50 %). 1  HRMS (ESI) m/z calcd for C15H8N2O5 (S-1 + ) 296.0418, found 296.0228.

3,7-Diaminodibenzosuberenone (C):
S-1 (400 mg, 1.34 mmol) was added to a 50 mL round bottom flask with stir bar, followed by addition of Raney© 2800 Ni suspension in water (1.0 mL) and MeOH (25 mL). The flask was fixed with a septum and purged with nitrogen gas. Hydrazine monohydrate (2.0 mL, 41.2 mmol) was slowly added.
After the addition, the reaction was stirred at room temperature. After 24 h the reaction mixture was diluted with acetone (100 mL) followed by filtering through celite. After evaporating the solvent in vacuo, the residue was triturated in deionized water (200 mL) before being filtered using celite. The filter was rinsed clean using MeOH (150 mL) before evaporating the solvent in vacuo to give an orangeyellow solid. This was recrystallized from EtOH to give product as an orange solid (162 mg, 50 %). 1

2,7-Dinitroxanthone (S-2)
Fuming nitric acid (15 mL) and concentrated sulfuric acid (10 mL) were added to a 250 mL round S-2 (100 mg, 0.33 mmol) was placed in a 50 mL round bottom flask with a stir bar followed by 10 mL of concentrated hydrochloric acid. Then, 4.5 equivalents of tin(II)chloride dihydrate was added to the flask. The reaction was refluxed for 12 h with stirring, then allowed to cool to room temperature. The reaction mixture was diluted with 50mL deionized water and brought to a pH of 8.5 using 2 M NaOH.
The yellow solution was then extracted using ethyl acetate until no color was present in the aqueous layer (3 x 15 mL). The solution was dried using anhydrous MgSO4, filtered and the solvent removed in vacou to yield an orange solid (57 mg, 72 %). 1

Assembly Mixing Experiments
General mixing procedure: All mixing experiments were performed in an NMR tube. One equivalent of dianiline A (3.5 mg, 0.015 mmol) and one equivalent of dianiline B (3.5 mg 0.015 mmol) were placed in an NMR tube. Deuterated acetonitrile (400 µL) was added to the tube and a proton spectrum of the dianiline mixture obtained. 2 equivalents of 2-formylpyridine were added (5µL, 0.029 mmol) followed by 0.66 equivalents of iron perchlorate (100 µL of 0.098 M Fe(ClO4)2•xH2O in CD3CN). A spectrum of the mixture was obtained. The tube was heated at 80 °C for 8 h. Another spectrum was taken after heating to show the favored cage and the unfavored dianiline ligand. A second 2 eq. of 2-formylpyridine and 0.66 eq. of iron perchlorate were added to the tube and a proton spectrum obtained. The tube was heated to 80 °C for 8 h. A final spectrum was obtained after heating to show both cages in solution.

Ligand Displacement Experiments
General displacement procedure: All displacement experiments were performed in an NMR tube. One equivalent of preformed Cage 1 (8.6 mg, 0.005 mmol) and three equivalents of dianiline B (3.5 mg 0.015 mmol) were placed in an NMR tube. Dry deuterated acetonitrile (400 µL) was added to the tube and a proton spectrum of the starting mixture obtained. The tube was heated at 80°C for 8 h. A second spectrum was obtained after heating to verify whether the preformed cage was displaced by the free dianiline ligand. Experiments were repeated with the addition of 6 molar equivalents of water and heated at 55°C for 1 hour. Figure S28: 1 H NMR spectra of anhydrous displacement experiment between cage 3 and dianiline A (CD3CN, 400 MHz, 298K). Top: Cage 1 (blue) and displaced dianiline C (orange) after heating at 80 °C for 8 h. Bottom: cage 3 (red) and dianiline A (green) prior to heating. The reverse experiment (cage 1 ligand displacement by dianiline C) showed no change in the spectrum even after heating for 24 h.