Synthesis
Step 1: Zinc cyanide (0.92 eq.) and tetrakis(triphenylphosphine)palladium (0.058 eq.) were sequentially added to a 1.0 eq. solution of 1-fluoro-3-iodo-5-nitrobenzene in anhydrous DMF (0.37 M) under nitrogen protection. The reaction mixture was heated to 80 °C and the reaction was stirred overnight. Subsequently, 0.023 equivalents of tetrakis(triphenylphosphine)palladium was added and the reaction continued to be stirred at 80°C for 6 hours. Upon completion of the reaction, the mixture was cooled to room temperature and diluted with 15 volumes of ethyl acetate (based on the amount of 1-fluoro-3-iodo-5-nitrobenzene). The organic phase was sequentially washed three times with water and once with saturated saline. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography with 10% ether/hexane as eluent to give 3-fluoro-5-nitrobenzonitrile as a solid in 90% yield.
References
[1] Patent: US2006/14761, 2006, A1. Location in patent: Page/Page column 29
[2] Patent: WO2007/75377, 2007, A2. Location in patent: Page/Page column 52-53
[3] Patent: WO2007/70626, 2007, A2. Location in patent: Page/Page column 40
[4] Patent: WO2007/70683, 2007, A2. Location in patent: Page/Page column 83
[5] Patent: WO2007/78839, 2007, A2. Location in patent: Page/Page column 40-41
