*2.1. Bulk Properties*

Tolane 1 was synthesized following the literature procedure and was obtained in a 72% yield [20]. Characterization: 1H NMR (400 MHz, CDCl3) δ<sup>H</sup> 7.56 (m, 4H), 7.47 (d, *J* = 8.1 Hz, 2H), 7.17 (d, *J* = 8.1 Hz, 2H), 2.60 (t, *J* = 7.5 Hz, 2H), 1.61 (q, *J* = 7.5 Hz, 2H), 1.31 (m, 4H), 0.91 (t, *J* = 6.8 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ<sup>C</sup> 144.5, 131.9, 131.9, 130.5, 129.6, 128.7, 127.6, 125.4, 119.9, 92.3, 87.6, 36.1, 31.6, 31.0, 22.7, 14.1. EI+-MS m/z 316 (M+); Anal. calcd. for: C20H19F3: %C, 75.93; %H, 6.05; found: %C, 75.88; %H, 5.97.

Differential scanning calorimetry (DSC) analysis revealed the existence of two main crystalline polymorphs melting at 69.7 and 71.3 ◦C, respectively. These transitions stabilized after two heating–cooling cycles (Figure 2).

**Figure 2.** Differential scanning calorimetry (DSC) of **1**, second heating (green) and cooling (blue) cycle.

The *N*-pyridyl-tolanes **4** and **5** were solid (**4**) or liquid (**5**) at room temperature, respectively. However, upon protonation (with hydrochloric or terephthalic acid), both formed crystalline solids. In addition, solid halogen bond complexes were obtained from **4** and **5** with suitable halogen bond donors. The terephthalate complex of protonated **4** was liquid crystalline over a wide temperature range. Hence, the material can be processed and measured conveniently in a conventional liquid crystal (LC) cell.
