Borole Derivatives. 24. Synthesis of Cationic
(Arene)(phenylborole)rhodium Complexes. Structures of
the Trinuclear Complex (η<sup>5</sup>-C<sub>4</sub>H<sub>4</sub>BPh)Rh(μ<sub>3</sub>-I)<sub>3</sub>-Rh(μ,η<sup>5</sup>:η<sup>6</sup>-C<sub>4</sub>H<sub>4</sub>BPh)Rh(η<sup>5</sup>-C<sub>4</sub>H<sub>4</sub>BMe)·CH<sub>2</sub>Cl<sub>2</sub> and of the
Polymeric <i>catena</i>-(μ,η<sup>5</sup>:η<sup>6</sup>-1-Phenylborole)rhodium
Tetrafluoroborate
Gerhard E. Herberich
Hartmut J. Eckenrath
Ulli Englert
10.1021/om970742+.s001
https://acs.figshare.com/articles/journal_contribution/Borole_Derivatives_24_Synthesis_of_Cationic_Arene_phenylborole_rhodium_Complexes_Structures_of_the_Trinuclear_Complex_sup_5_sup_-C_sub_4_sub_H_sub_4_sub_BPh_Rh_sub_3_sub_-I_sub_3_sub_-Rh_sup_5_sup_sup_6_sup_-C_sub_4_sub_H_sub_4_sub_BPh_Rh_sup_5_sup_-C_sub/3780939
The heterocubane
[Rh(μ<sub>3</sub>-I)(C<sub>4</sub>H<sub>4</sub>BPh)]<sub>4</sub>
(<b>1</b>) reacts with Ag<sup>+</sup> salts in acetonitrile to
give
the labile salt
[Rh(NCMe)<sub>3</sub>(C<sub>4</sub>H<sub>4</sub>BPh)]BF<sub>4</sub>
(<b>2</b>). This salt <b>2</b> reacts with
hexamethylbenzene
(hmb) to give the arene complex
[Rh(C<sub>4</sub>H<sub>4</sub>BPh)(hmb)]BF<sub>4</sub>
(<b>3</b>), and with mesitylene [Rh(1,3,5-C<sub>6</sub>H<sub>3</sub>Me<sub>3</sub>)(C<sub>4</sub>H<sub>4</sub>BPh)]BF<sub>4</sub>
(<b>4</b>) is obtained. Complex <b>2</b> loses
acetonitrile under vacuum to
produce the polymeric salt
<i>catena</i>-[{Rh(μ,η<sup>5</sup>:η<sup>6</sup>-C<sub>4</sub>H<sub>4</sub>BPh)}BF<sub>4</sub>]<i><sub>x</sub></i>
(<b>5</b>). Insight into the essential
structural features of this polymer provided its radial distribution
function obtained from a
wide-angle X-ray scattering experiment. When treated with
acetonitrile, complex <b>5</b> regenerates <b>2</b> and with pyridine affords
[Rh(py)<sub>3</sub>((C<sub>4</sub>H<sub>4</sub>BPh)]BF<sub>4</sub>
(<b>6</b>). Crystallization from a solution of
[Rh(μ<sub>3</sub>-I)(C<sub>4</sub>H<sub>4</sub>BPh)]<sub>4</sub>
(<b>1</b>) and the corresponding methylborole complex
[Rh(μ<sub>3</sub>-I)(C<sub>4</sub>H<sub>4</sub>BMe)]<sub>4</sub> (1/1) in
CH<sub>2</sub>Cl<sub>2</sub> produces the trinuclear complex
(η<sup>5</sup>-C<sub>4</sub>H<sub>4</sub>BPh)Rh(μ<sub>3</sub>-I)<sub>3</sub>Rh(μ,η<sup>5</sup>:η<sup>6</sup>-C<sub>4</sub>H<sub>4</sub>BPh)Rh(η<sup>5</sup>-C<sub>4</sub>H<sub>4</sub>BMe)·CH<sub>2</sub>Cl<sub>2</sub>
(<b>7</b>) with a bridging
μ,η<sup>5</sup>:η<sup>6</sup>-C<sub>4</sub>H<sub>4</sub>BPh
ligand; complex
<b>7</b> was characterized by an X-ray structure determination.
The resulting molecular structure
was used to create a structure model for the monomeric building block
of polymer <b>5</b>.
1998-02-16 00:00:00
Rh
distribution function
Borole Derivatives
structure model
24. Synthesis
Complex 2
polymer 5
monomeric building block
CH 2 Cl 2
salt 2
C 4 H 4 BPh ligand