## 4 Precursors to Materials
### Energy and Electronics  
For further development of lithium-ion batteries, it is essential to prepare less flammable and easily processable materials. In this sense, [PERSON] and co-workers [194] studied the structure and ionic conductivity of liquid crystals containing propylene carbonate units (Schemes 75 and 76). The interest in this class of compounds is due to their thermal stability, high dielectric constant, and good lithium ion conductivity at room temperature [195]. The authors prepared type **160** liquid crystalline molecules bearing a cyclic carbonate endpoint (Scheme 75). The ionic conductivity of the tetrafluorinated compound **160a** was compared with that of the non-fluorinated analogue **161a** (Scheme 76), while **160b** was compared to the tetra(ethylene oxide) (TEO) analogue **162a** (Scheme 75), which bears the same fluorinated mesogenic core. The fluorinated precursor **163** was obtained in 2 steps from 2,3,5,6-tetrafluorophenol, while the non-fluorinated precursor **164a** was prepared from 4-hydroxybenzoic acid. Liquid crystals **160a** and **161a** were obtained with satisfactory yields via the esterification with GC **1a** under mild reaction conditions. The TEO analogue **162** was synthesized with 65% yield via a sequential BH\({}_{3}\)-THF reduction of **163c**, followed by the Cs\({}_{2}\)CO\({}_{3}\)-catalyzed etherification of the benzylic alcohol **166** using the TEO toylate **167a**. **Scheme 76. Synthesis of the non-fluorinated analogue **161**. After mixing the synthesized compounds with lithium bis(trifluoro-methanesulfonyl)-imide (LiTFSI), the authors observed that Li\({}^{+}\) self-assembly was driven by the interaction with the carbonate units via coordination with the free electron pairs of oxygen. Furthermore, the cyclic carbonate moiety present in **160** and **161** enhanced the lithium salt dissociation as compared to the TEO derivative **162**. Measurements by small- and wide-angle X-ray scattering (SAXS/WAXS) demonstrated that the compounds align spontaneously in the smectic phase when cooled from the isotropic melt. The formation of a smectic layer improves the ionic conductivity by enhancing the ion mobility parallel to the layer plane. Another interesting study involving GC **1a** was reported by [PERSON] and co-workers in 2016 [196]. In this work, **1a** was reacted with furfuryl amine **63g** to provide the urethanes **168a-b** (Scheme 77). After a few more reaction steps, a surface of polydimethylsiloxane-based polyurethane cross-linked by Diels-Alder adducts **169** was prepared. In the sequence, silver nanowire (AgNW) was deposited on this surface via vapor-assisted solution process, resulting in a highly flexible, transparent, and healable electrode. In 2020, [PERSON] and co-workers [197] synthesized several fluorescent macrocycles **171** through the iridium-catalyzed intermolecular decarboxylate coupling of vinylated carbonate **1e** with readily available isatoic anhydrides **170** (Scheme 78). The best reaction conditions were obtained with [Ir(cod)(OMe)]\({}_{2}\) (2.0 mol%) as the catalyst, 2,2\({}^{\prime}\)-bipyridine as the chelating \(N\),\(N\)-donor ligand, and a mixture DCM/acetone (3:1) as the solvent. The sequential allyl-amination-macrolactonization upon extrusion of CO\({}_{2}\) provided the expected benzo-fused, 14-membered _aza_-macrolides **171** with moderate yields after 12 h of reaction. The scope was evaluated using isatoic anhydrides **170** bearing electron-donating (Me and CH\({}_{3}\)) and electron-withdrawing groups (halides and CF\({}_{3}\)). Azamacrolides **171** showed favorable fluorescence emission in the 397-430 nm range. The proposed reaction mechanism starts with the Ir(I)-catalyzed decarboxylation of **1e** to generate the zwitterionic \(p\)-allyl iridium intermediate A. After tautomerization of A,an electrophilic six-membered iridacyclic species B is formed. Then, the intermediate B is trapped by the nucleophilic amino group of **170a**, giving the intermediate C and the active Ir(I) catalyst for the next catalytic cycle.