10.1021/om970739q.s001
Mara Staffilani
Mara
Staffilani
Giuliana Bonvicini
Giuliana
Bonvicini
Jonathan W. Steed
Jonathan W.
Steed
K. Travis Holman
K. Travis
Holman
Jerry L. Atwood
Jerry L.
Atwood
Mark R. J. Elsegood
Mark
R. J. Elsegood
Bowl vs Saddle Conformations in Cyclononatriene-Based
Anion Binding Hosts
American Chemical Society
1998
Ru
BF
CHMe
bowl vs Saddle Conformations
binding constants
2 n
1 H NMR titration studies
anion affinity
MeC
bind anions
1 H NMR
complexes 6
nitromethane solution
host 2 displays
CF
anion complexation behavior
saddle conformation
ligand 4
9 results
crystallography
1998-04-03 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Bowl_vs_Saddle_Conformations_in_Cyclononatriene-Based_Anion_Binding_Hosts/3780933
The synthesis of organometallic complexes
[{Ru(<i>p</i>-MeC<sub>6</sub>H<sub>4</sub>CHMe<sub>2</sub>)}<i><sub>n</sub></i>(C<sub>21</sub>H<sub>24</sub>S<sub>3</sub>)][CF<sub>3</sub>SO<sub>3</sub>]<sub>2</sub><i><sub>n</sub></i>
(<i>n</i> = 1, <b>6</b>; <i>n</i> = 2, <b>7</b>)
and
[{Ir(C<sub>5</sub>Me<sub>5</sub>)}<sub>2</sub>(C<sub>21</sub>H<sub>24</sub>S<sub>3</sub>)][CF<sub>3</sub>SO<sub>3</sub>]<sub>4</sub>
(<b>9</b>) based upon the trimeric
macrocycle cyclotris(dimethylthiophenylene) (<b>4</b>) is
reported. A saddle conformation is
identified for the free ligand <b>4</b> and complexes <b>6</b>
and <b>9</b> by X-ray crystallography. The anion
complexation behavior of complex <b>9</b> is compared with the
related cyclotriveratrylene complex
[{Ru(<i>p</i>-MeC<sub>6</sub>H<sub>4</sub>CHMe<sub>2</sub>)}<sub>2</sub>(C<sub>27</sub>H<sub>30</sub>O<sub>6</sub>)][CF<sub>3</sub>SO<sub>3</sub>]<sub>4</sub>
(<b>2</b>), which possesses a bowl-shaped conformation, by <sup>1</sup>H NMR titration studies in a variety of solvents.
While host <b>2</b> displays a significant
affinity for halides with binding constants of up to 1.25(7) ×
10<sup>3</sup> M<sup>-1</sup> in nitromethane
solution,
the absence of a molecular cavity in <b>9</b> results in very
little specific anion affinity. The 1,3-alternate calix[4]arene complex
[{Ru(η<sup>6</sup>-<i>p-</i>MeC<sub>6</sub>H<sub>4</sub>CHMe<sub>2</sub>)}<sub>2</sub>(η<sup>6</sup>:η<sup>6</sup>-C<sub>40</sub>H<sub>48</sub>)][BF<sub>4</sub>]<sub>4</sub>
(<b>11</b>) is also
reported and shown to bind anions in an unusual
C−H···anion hydrogen-bonding fashion
by X-ray crystallography and <sup>1</sup>H NMR.