# Synthesis, Characterization, and Self-Assembly of a Tetrathiafulvalene (TTF)-Triglycyl Derivative
## 2 Materials and Methods
### Synthesis and Characterization of Compounds
#### 2.2.2 Synthetic Procedures and Characterization of Compounds
2-(2-Cyanoethylthio)-3,6,7-_tris_(butylthio)tetrathiafulvalene (**6**): A solution of CsOH\(\cdot\)H\({}_{2}\)O (365 mg, 2.12 mmol) in dry methanol (MeOH) (15 mL) was added dropwise over a period of 30 min to a stirred solution of TTF derivative **5** (1.13 g, 2.07 mmol) in tetrahydrofuran (THF) (40 mL). The resulting orange solution was stirred for 30 min at RT. To this solution, 1-bromobutane (**2**) (0.44 mL, 4.14 mmol) dissolved in THF (15 mL) was added and the resulting mixture was stirred overnight (o.n.) at RT under nitrogen atmosphere. The mixture was concentrated to dryness and the resulting oil was purified by flash chromatography on silica gel (DCM/hexane 1:1\(\rightarrow\)2:1) giving the desired compound **6** as an orange solid (1.09 g, 89% yield). TLC in DCM/hexane 2:1, R\({}_{f}\) = 0.45. \({}^{1}\)H-NMR (400 MHz, CDCl\({}_{3}\)) \(\delta\) (ppm): 3.01 (t, \(J\) = 7.2 Hz, 2H, SCH\({}_{2}\)-CH\({}_{2}\)-CN), 2.87-2.78 (m, 6H, SCH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{3}\)), 2.68 (t, \(J\) = 7.2 Hz, 2H, SCH\({}_{2}\)-CH\({}_{2}\)-CN), 1.65-1.57 (m, 6H, SCH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{3}\)), 1.47-1.38 (m, 6H, SCH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{3}\)), 0.93-0.89 (m, 9H, CH\({}_{3}\)). \({}^{13}\)C-NMR (100 MHz, CDCl\({}_{3}\)) \(\delta\) (ppm): 133.71, 127.92, 127.61 and 121.83 (-CH\({}_{2}\)-S-C-S-), 117.53 (CN), 112.36 and 108.27 (S\({}_{2}\)=CS\({}_{2}\)), 36.02 and 35.98 (S-CH\({}_{2}\)-), 31.77 and 31.73 (S-CH\({}_{2}\)-CH\({}_{2}\)-), 31.24 (S-CH\({}_{2}\)-CH\({}_{2}\)-CN), 21.62 (S-CH\({}_{2}\)-CH\({}_{2}\)-\({}_{2}\)-\({}_{2}\)-), 18.69 (S-CH\({}_{2}\)-CH\({}_{2}\)-CN), 13.57 and 13.53 (-CH\({}_{3}\)). IR (solid): v = 2954 s, 2925 s and 2870 m (C-H stretch), 2250 w (C\(\equiv\)N stretch), 1463 m (H-C-H bend), 1412 m (C-H stretch), 890 s (H-C-S bend), 772 m-s and 742 m-s (C-S stretch) cm\({}^{-1}\). HRMS (ESI\({}^{+}\)): \(m/z\): calcd for C\({}_{21}\)H\({}_{31}\)NS\({}_{8}\) 554.0300; found 554.0288. 3-[[4\({}^{\prime}\),5,5\({}^{\prime}\)_-TriS_(butylsulfonyl)-2,2\({}^{\prime}\)-bi-1,3-dithiol-4-yl]sulfonyl]propionic acid (**8**): (2-Cyanoethyl)sulfanyl TTF derivative **6** (1.01 g, 1.82 mmol) was dissolved in anhydrous THF (40 mL) and a solution of CsOH\(\cdot\)H\({}_{2}\)O (0.32 g, 1.9 mmol) in anhydrous MeOH (15 mL) was added. After stirring the reaction mixture at RT for 30 min, a suspension of 3-bromopropionic acid (7, Sigma-Aldrich) (0.56 g, 3.6 mmol) and freshly annealed K\({}_{2}\)CO\({}_{3}\) (1.39 g, 10 mmol) in anhydrous MeOH (15 mL) was added. The reaction mixture was stirred at RT for 3 h and concentrated to dryness. The obtained residue was dissolved in Et\({}_{2}\)O (230 mL) and 1M HCl aqueous solution (150 mL) was added slowly. The organic phase was washed with water (100 mL) and brine (100 mL), dried over anhydrous MgSO\({}_{4}\) and concentrated to dryness under reduced pressure. The obtained residue was purified by chromatography on silica gel (DCM/MeOH 100:0\(\rightarrow\)90:10) affording the desired compound **8** as an orange solid (0.95 g, 91% yield). TLC in DCM/MeOH 10:0.5, R\({}_{f}\) = 0.50. \({}^{1}\)H NMR (400 MHz, CDCl\({}_{3}\)), \(\delta\) (ppm): 3.03 (t, \(J\) = 7.2 Hz, 2H, SCH\({}_{2}\)-CH\({}_{2}\)-COOH), 2.83-2.79 (m, 6H, SCH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{3}\)), 2.72 (t, \(J\) = 7.2 Hz, 2H, SCH\({}_{2}\)-CH\({}_{2}\)-COOH), 1.63-1.56 (m, 6H, C-SCH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{3}\)), 1.47-1.37 (m, 6H, C-SCH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{3}\)), 1.47-1.37 (m, 6H, C-SCH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{3}\)), 0.91 (t, \(J\) = 7.2 Hz, 9H, CH\({}_{3}\)). \({}^{13}\)C-NMR (100 MHz, CDCl\({}_{3}\)) \(\delta\) (ppm): 176.78 (COOH), 131.10, 127.87, 127.61 and 124.70 (-CH\({}_{2}\)-S-C-S-), 111.17 and 109.22 (S\({}_{2}\)=CS\({}_{2}\)), 35.99 and 36.96 (S-CH\({}_{2}\)-), 34.41 (SCH\({}_{2}\)-CH\({}_{2}\)-COOH), 31.74 (S-CH\({}_{2}\)-CH\({}_{2}\)-CHO\({}_{2}\)), 30.48 (SCH\({}_{2}\)-CH\({}_{2}\)-COOH), 21.63 (S-CH\({}_{2}\)-CH\({}_{2}\)-CH\({}_{2}\)-), 13.57 and 13.54 (-CH\({}_{3}\)).