@article{LandmannHennigIgnat'evetal.2017, author = {Landmann, Johannes and Hennig, Philipp T. and Ignat'ev, Nikolai V. and Finze, Maik}, title = {Borylation of fluorinated arenes using the boron centred nucleophile B(CN)\(_{3}\)\(^{2-}\) - a unique entry to aryltricyanoborates}, series = {Chemical Science}, volume = {8}, journal = {Chemical Science}, number = {9}, doi = {10.1039/c7sc02249b}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170417}, pages = {5962-5968}, year = {2017}, abstract = {The potassium salt of the boron-centred nucleophile B(CN)\(_{3}\)\(^{2-}\)(1) readily reacts with perfluorinated arenes, such as hexafluorobenzene, decafluorobiphenyl, octafluoronaphthalene and pentafluoropyridine, which results in KF and the K\(^{+}\) salts of the respective borate anions with one {B(CN)\(_{3}\)} unit bonded to the (hetero)arene. An excess of K\(_{2}\)1 leads to the successive reaction of two or, in the case of perfluoropyridine, even three C-F moieties and the formation of di- and trianions, respectively. Moreover, all of the 11 partially fluorinated benzene derivatives, C\(_{6}\)F\(_{6-n}\)H\(_{n}\) (n = 1-5), generally react with K\(_{2}\)1 to give new tricyano(phenyl)borate anions with high chemo- and regioselectivity. A decreasing number of fluorine substituents on benzene results in a decrease in the reaction rate. In the cases of partially fluorinated benzenes, the addition of LiCl is advantageous or even necessary to facilitate the reaction. Also, pentafluorobenzenes R-C\(_{6}\)F\(_{5}\) (R = -CN, -OMe, -Me, or -CF\(_{3}\)) react via C-F/C-B exchange that mostly occurs in the para position and to a lesser extent in the meta or ortho positions. Most of the reactions proceed via an S\(_{N}\)Ar mechanism. The reaction of 1,4-F\(_{2}\)C\(_{6}\)H\(_{4}\) with K\(_{2}\)1 shows that an aryne mechanism has to be considered in some cases as well. In summary, a wealth of new stable tricyano(aryl)borates have been synthesised and fully characterized using multi-NMR spectroscopy and most of them were characterised using single-crystal X-ray diffraction.}, language = {en} }