Dynamic Behavior of
N‑Heterocyclic Carbene
Boranes: Boron–Carbene Bonds in <i>B</i>,<i>B</i>‑Disubstituted <i>N</i>,<i>N</i>‑Dimethylimidazol-2-ylidene Boranes Have Substantial Rotation
Barriers
Krishnan Damodaran
Xiben Li
Xiangcheng Pan
Dennis P. Curran
10.1021/acs.joc.5b00324.s001
https://acs.figshare.com/articles/journal_contribution/Dynamic_Behavior_of_N_Heterocyclic_Carbene_Boranes_Boron_Carbene_Bonds_in_i_B_i_i_B_i_Disubstituted_i_N_i_i_N_i_Dimethylimidazol_2_ylidene_Boranes_Have_Substantial_Rotation_Barriers/2170642
Dynamic
NMR spectroscopy has been used to measure rotation barriers
in five <i>B</i>,<i>B</i>-disubstituted 1,3-dimethylimidazol-2-ylidene
boranes. The barriers are attributed to the sp<sup>2</sup>–sp<sup>3</sup> bond between C(1) of the N-heterocyclic carbene ring and
the boron atom. Bonds to boron atoms bearing a thexyl (1,1,2-trimethylpropyl)
group show especially high barriers, ranging from 75–86 kJ
mol<sup>–1</sup>. 2-Isopropyl-1,3,5-trimethylbenzene is used
as a comparable to help understand the nature and magnitude of the
barriers.
2015-05-01 00:00:00
group show
boron atom
measure rotation barriers
boron atoms
Dynamic Behavior
Bond
Substantial Rotation BarriersDynamic NMR spectroscopy
Borane