TY  - JOUR
A1  - Trageser, Timo
A1  - Bebej, Dariusz
A1  - Bolte, Michael
A1  - Lerner, Hans-Wolfram
A1  - Wagner, Matthias
T1  - B–B vs. B–H Bond Activation in a (μ-Hydrido)diborane(4) Anion upon Cycloaddition with CO₂, Isocyanates, or Carbodiimides
T2  - Angewandte Chemie
N2  - The intriguing (μ-hydrido)diboranes(4) with their prominent pristine representative [B2H5]− have mainly been studied theoretically. We now describe the behavior of the planarized tetraaryl (μ-hydrido)diborane(4) anion [1H]− in cycloaddition reactions with the homologous series of heterocumulenes CO2, iPrNCO, and iPrNCNiPr. We show that a C=O bond of CO2 selectively activates the B−B bond of [1H]−, while the μ-H ligand is left untouched ([2H]−). The carbodiimide iPrNCNiPr, in contrast, neglects the B−B bond and rather adds the B-bonded H− ion to its central C atom to generate a formamidinate bridge across the B2 pair ([3]−). As a hybrid, the isocyanate iPrNCO combines the reactivity patterns of both its congeners and gives two products: one of them ([4H]−) is related to [2H]−, the other ([5]−) is an analog of [3]−. We finally propose a mechanistic scenario that rationalizes the individual reaction outcomes and combines them to a coherent picture of B–B vs. B–H bond activation.
KW  - B−B bonds
KW  - B−H bonds
KW  - bond activation
KW  - cycloaddition
KW  - diboranes
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/63883
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-638835
SN  - 1521-3773
N1  - T.T. thanks the Fonds der Chemischen Industrie for a Ph.D. grant. Open access funding enabled and organized by Projekt DEAL.
VL  - 60
IS  - 24
SP  - 13500
EP  - 13506
PB  - Wiley-VCH
CY  - Weinheim
ER  -