TY  - JOUR
A1  - Häring, Mathias
A1  - Kerpen, Christoph
A1  - Ribbeck, Tatjana
A1  - Hennig, Philipp T.
A1  - Bertermann, Rüdiger
A1  - Ignat’ev, Nikolai V.
A1  - Finze, Maik
T1  - Dismutation of Tricyanoboryllead Compounds: The Homoleptic Tetrakis(tricyanoboryl)plumbate Tetraanion
JF  - Angewandte Chemie
N2  - A series of unprecedently air-stable (tricyanoboryl)plumbate anions was obtained by the reaction of the boron-centered nucleophile B(CN)\(_{3}\)\(^{2-}\) with triorganyllead halides. Salts of the anions [R\(_{3}\)PbB(CN)\(_{3}\)]\(^{-}\) (R=Ph, Et) were isolated and found to be stable in air at room temperature. In the case of Me\(_{3}\)PbHal (Hal=Cl, Br), a mixture of the anions [Me\(_{4-n}\)Pb{B(CN)\(_{3}\)}\(_{n}\)]\(^{n-}\) (n=1, 2) was obtained. The [Et\(_{3}\)PbB(CN)\(_{3}\)]− ion undergoes stepwise dismutation in aqueous solution to yield the plumbate anions [Et4\(_{4-n}\)Pb{B(CN)\(_{3}\)}\(_{n}\)]\(^{n-}\) (n=1–4) and PbEt\(_{4}\) as by-product. The reaction rate increases with decreasing pH value of the aqueous solution or by bubbling O\(_{2}\) through the reaction mixture. Adjustment of the conditions allowed the selective formation and isolation of salts of all anions of the series [Et\(_{4-n}\)Pb{B(CN)\(_{3}\)}\(_{n}\)]\(^{n-}\) (n=2–4) including the homoleptic tetraanion [Pb{B(CN)\(_{3}\)}\(_{4}\)]\(^{4-}\).
KW  - anions
KW  - boron
KW  - cyanoborates
KW  - dismutations
KW  - lead
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318257
VL  - 61
IS  - 24
ER  - 
TY  - JOUR
A1  - Drisch, Michael
A1  - Bischoff, Lisa A.
A1  - Sprenger, Jan A. P.
A1  - Hennig, Philipp T.
A1  - Wirthensohn, Raphael
A1  - Landmann, Johannes
A1  - Konieczka, Szymon Z.
A1  - Hailmann, Michael
A1  - Ignat'ev, Nikolai V.
A1  - Finze, Maik
T1  - Innovative Syntheses of Cyano(fluoro)borates: Catalytic Cyanation, Electrochemical and Electrophilic Fluorination
JF  - Chemistry – A European Journal
N2  - Different types of high‐yield, easily scalable syntheses for cyano(fluoro)borates Kt[BF\(_{n}\)(CN)\(_{4-n}\)] (n=0–2) (Kt=cation), which are versatile building blocks for materials applications and chemical synthesis, have been developed. Tetrafluoroborates react with trimethylsilyl cyanide in the presence of metal‐free Brønsted or Lewis acid catalysts under unprecedentedly mild conditions to give tricyanofluoroborates or tetracyanoborates. Analogously, pentafluoroethyltrifluoroborates are converted into pentafluoroethyltricyanoborates. Boron trifluoride etherate, alkali metal salts, and trimethylsilyl cyanide selectively yield dicyanodifluoroborates or tricyanofluoroborates. Fluorination of cyanohydridoborates is the third reaction type that includes direct fluorination with, for example, elemental fluorine, stepwise halogenation/fluorination reactions, and electrochemical fluorination (ECF) according to the Simons process. In addition, fluorination of [BH(CN)\(_{2}\){OC(O)Et}]\(^{-}\) to result in [BF(CN)\(_{2}\){OC(O)Et}]\(^{-}\) is described.
KW  - cyanoborates
KW  - electrochemical fluorination
KW  - fluorination
KW  - fluoroborates
KW  - ionic liquids
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-216027
VL  - 26
IS  - 50
SP  - 11625
EP  - 11633
ER  - 
TY  - JOUR
A1  - Landmann, Johannes
A1  - Hennig, Philipp T.
A1  - Ignat'ev, Nikolai V.
A1  - Finze, Maik
T1  - Borylation of fluorinated arenes using the boron centred nucleophile B(CN)\(_{3}\)\(^{2-}\) - a unique entry to aryltricyanoborates
JF  - Chemical Science
N2  - 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.
KW  - borylation
KW  - boron-centred nucleophile
KW  - aryltricyanoborates
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170417
VL  - 8
IS  - 9
ER  -