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The synthesis of the bidentate Mo complex tetrachlorido[6-(3’-butylimidazolium-1’-yl)-2-(3’’-butylimidazol-1’’-yl-2’’-idene-κC2)phenyl-κC1]molybdenum(IV) 3 was carried out using the metalation followed by transmetalation methodology. The transmetallation process led to a bidentate complex after reaction of DCM with HNMe2 formed an acidic ammonium ion that protonated the bidentate complex. Optimization of the synthetic methodology provided the tetrachlorido[6-(3’-butylimidazolium-1’-yl)-2-(3’’-butylimidazol-1’’-yl-2’’-idene-κC2)phenyl-κC1]molybdenum(IV) complex in high yield. The crystal structure of the bidentate complex, 3, is reported herein. Attempts to avoid the acidic reaction conditions with different solvents or starting materials produced the bis-ligated Mo complex bis[2,6-bis(3’-butylimidazol-1’-yl-2’-idene-κC2)phenyl-κC1]molybdenum(IV) dichloride based on MS analysis. Electronic and coordinative unsaturation in the resulting bidentate complex, 3, open new possibilities for coordination of incoming substrates while also allowing access to the pincer-like motif via oxidative addition. Access to the interconversion of a NHC to/from imidazolium opens new avenues of non-innocent ligand pathways for proton shuttling in reactions such as nitrogen reduction to ammonia. 

Integration of polycyclic aromatic hydrocarbon (PAH) units into semi-fluorinated polymers affords high thermal stability and excellent processability for potential applications in optoelectronic, gas-separation, and advanced composites. Base-promoted step-growth polycondensation of commercial bisphenols with new triphenylene containing bis-trifluorovinyl ether (TFVE) monomers affords semi-fluorinated arylene vinylene ether (FAVE) polymers in good yields. The solution-processable polymers form tough transparent films and produce substitution dependent blue-light emission in solution with emission quantum yields ranging from 7.2–12% (in dichloromethane). Although predominantly amorphous with high glass transition temperatures ( T g ) ranging from 176–243 °C, powder X-ray diffraction studies show typical molecular diameter and pi-stacking reflections for triphenylene polymers. The polymers exhibited excellent thermal stability, solution photostability, and remarkable thermal oxidative photostability after heating at 250 °C for 24 h in air. Further, a model post-polymerization Scholl coupling afforded a novel semi-fluorinated hexabenzocoronene polymer with new optical properties. Time-dependent density functional theory (TD-DFT) computations were also performed using SMD (dichloromethane)- ω B97XD/BS1 (BS1 = 6-31G(d′) for C, H, O and F). This work demonstrated the synthesis and characterization of processable, blue-light emitting, thermally stable triphenylene enchained semi-fluorinated aryl ether polymers.