TY  - JOUR
A1  - Budy, Hendrik
A1  - Kaese, Thomas
A1  - Bolte, Michael
A1  - Lerner, Hans-Wolfram
A1  - Wagner, Matthias
T1  - A chemiluminescent tetraaryl diborane(4) tetraanion
T2  - Angewandte Chemie
N2  - Two subvalent, redox-active diborane(4) anions, [3]4− and [3]2−, carrying exceptionally high negative charge densities are reported: Reduction of 9-methoxy-9-borafluorene with Li granules without stirring leads to the crystallization of the B(sp3)−B(sp2) diborane(5) anion salt Li[5]. [5]− contains a 2,2′-biphenyldiyl-bridged B−B core, a chelating 2,2′-biphenyldiyl moiety, and a MeO substituent. Reduction of Li[5] with Na metal gives the Na+ salt of the tetraanion [3]4− in which two doubly reduced 9-borafluorenyl fragments are linked via a B−B single bond. Comproportionation of Li[5] and Na4[3] quantitatively furnishes the diborane(4) dianion salt Na2[3], the doubly boron-doped congener of 9,9′-bis(fluorenylidene). Under acid catalysis, Na2[3] undergoes a formal Stone–Wales rearrangement to yield a dibenzo[g,p]chrysene derivative with B=B core. Na2[3] shows boron-centered nucleophilicity toward n-butyl chloride. Na4[3] produces bright blue chemiluminescence when exposed to air.
KW  - 9-borafluorene
KW  - boryl anions
KW  - chemiluminescence
KW  - redox chemistry
KW  - subvalent compounds
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/63927
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-639271
SN  - 1521-3773
N1  - Open access funding enabled and organized by Projekt DEAL.
VL  - 60
IS  - 35
SP  - 19397
EP  - 19405
PB  - Wiley-VCH
CY  - Weinheim
ER  -