The synthesis is outlined in Schemes S1 and S2. The intermediate DCzB-Bpin was reacted with 4-bromo-3,5-difluorobenzonitrile under Suzuki-Miyaura cross-coupling conditions to afford DCzBDFCN in 96% yield. DCzBDFCN was then reacted with 3,6-di-tertbutylcarbazole and 2GtBuCz under SNAr conditions to obtain the target compounds, 2GtBuCzCO2HDCzB and tBuCzCO2HDCzB, in 60 and 38% yield, respectively. The two emitters were purified by silica gel chromatography followed by gel permeation chromatography. During the SNAr reaction, the benzonitrile was hydrolysed to the benzoate in both emitters, which was confirmed by high-resolution mass spectrometry (HRMS) and elemental analysis (Figure and S20). By contrast, for tBuCzCN and 2GBuCzCN the ).