10.1021/ic971105e.s001
Alain Diebold
Alain
Diebold
Karl S. Hagen
Karl S.
Hagen
Iron(II) Polyamine Chemistry: Variation of Spin State and Coordination Number in Solid
State and Solution with Iron(II) Tris(2-pyridylmethyl)amine Complexes
American Chemical Society
1998
4.
ligand
TPA
OH
presence
FeN
Fe
3 CF 3
CH
CN
solution coordination chemistry
NMR
BPh 4
OTf
1998-01-26 00:00:00
Dataset
https://acs.figshare.com/articles/dataset/Iron_II_Polyamine_Chemistry_Variation_of_Spin_State_and_Coordination_Number_in_Solid_State_and_Solution_with_Iron_II_Tris_2-pyridylmethyl_amine_Complexes/3620286
The synthetic system of
Fe(SO<sub>3</sub>CF<sub>3</sub>)<sub>2</sub> and one or
two TPA ligands (TPA = tris(2-pyridylmethyl)amine)
affords
a series of complexes that demonstrate the complexities of the
solid-state and solution coordination chemistry of
labile iron(II) even with a multidentate ligand. The low-spin
[Fe(TPA)(CH<sub>3</sub>CN)<sub>2</sub>](SO<sub>3</sub>CF<sub>3</sub>)<sub>2</sub>
(<b>1</b>-OTf) complex
forms in acetonitrile, but the high-spin complex
Fe(TPA)(SO<sub>3</sub>CF<sub>3</sub>)<sub>2</sub>
(<b>2</b>) forms in chloroform. The methanol-bound complex
[Fe(TPA)(CH<sub>3</sub>OH)<sub>2</sub>](BPh<sub>4</sub>)<sub>2</sub>
(<b>3</b>) forms in the presence of the noncoordinating anion,
BPh<sub>4</sub><sup>-</sup>, and
six-coordinate
[Fe(TPA)<sub>2</sub>](SO<sub>3</sub>CF<sub>3</sub>)<sub>2</sub>
(<b>4</b>-OTf) and eight-coordinate
[Fe(TPA)<sub>2</sub>](BPh<sub>4</sub>)<sub>2</sub>
(<b>4</b>-BPh<sub>4</sub>) form in the presence
of excess ligand. Their behavior in solution is explored by
studying their magnetic properties and NMR spectra,
which indicate the presence of spin and coordination equilibria.
The crystal structures of these complexes are
reported. Crystallographic parameters are as follows.
<b>1</b>-OTf·CH<sub>3</sub>CN:
C<sub>26</sub>H<sub>27</sub>F<sub>6</sub>FeN<sub>7</sub>O<sub>6</sub>S<sub>2</sub>,
monoclinic, <i>P</i>2<sub>1</sub>/<i>n</i>,<i>
a</i>
= 12.418(2) Å, <i>b</i> = 16.192(4) Å, <i>c</i>
= 15.855(2) Å, β = 92.09(2)°, <i>Z</i> = 4.
<b>2</b>:
C<sub>20</sub>H<sub>18</sub>F<sub>6</sub>FeN<sub>4</sub>O<sub>6</sub>S<sub>2</sub>,
monoclinic,
<i>P</i>2<sub>1</sub>/<i>c</i>,<i> a</i> =
17.636(2) Å, <i>b</i> = 9.659(1) Å, <i>c</i> =
16.004(2) Å, β = 113.29 (1)°, <i>Z</i> = 4.
<b>3</b>·CH<sub>3</sub>OH:
C<sub>69</sub>H<sub>70</sub>B<sub>2</sub>FeN<sub>4</sub>O<sub>3</sub>, monoclinic,
<i>P</i>2<sub>1</sub>/<i>n</i>,<i> a</i> =
17.525(1) Å, <i>b</i> = 19.150(2) Å, <i>c</i> =
17.703(1) Å, β = 100.36(1)°, <i>Z</i> = 4.
<b>4</b>-OTf:
C<sub>38</sub>H<sub>36</sub>F<sub>6</sub>FeN<sub>8</sub>O<sub>6</sub>S<sub>2</sub>,
monoclinic, <i>Pc</i>,<i> a</i> = 10.236(1) Å,
<i>b</i> = 10.129(1) Å, <i>c</i> = 19.251(1) Å,
β = 92.27(1)°, <i>Z</i> =
2. <b>4</b>-BPh<sub>4</sub>:
C<sub>84</sub>H<sub>76</sub>B<sub>2</sub>FeN<sub>8</sub>,
monoclinic, <i>P</i>2<sub>1</sub>/<i>n</i>,<i> a</i> =
12.489(1) Å, <i>b</i> = 14.189(1) Å, <i>c</i> =
19.843(1) Å, β = 102.84(1)°, <i>Z</i> = 2.