S
1
Thermodynamics of Proton and Electron Transfer in Tetranuclear Clusters with
Mn
–
OH
2
/OH
Motifs Relevant to H
2
O Activation by the Oxygen Evolving
Complex in Photosystem II
Christopher J. Reed, and Theodor Agapie*
Division of Chemistry and Chemical
Engineering, California Institute of Technology
Pasadena, California 91125, United States, Email: agapie@caltech.edu
Supporting Information
S
2
Table of Contents
Experimental Procedures
................................
................................
................................
...........
S
5
Figure S1.
1
H NMR spectra (300 MHz) of [LFe
3
O(Pz)
3
Mn]
[OTf] (
1
-
[OTf]
) and
[LFe
3
O(Pz)
3
Mn]
[
BAr
F
4
]
(
1
-
[BAr
F
4
]
)
................................
................................
.........................
S1
2
Figure S2.
19
F NMR spectra (300 MHz) of
[LFe
3
O(Pz)
3
Mn]
[OTf] (
1
-
[OTf]
) and
[LFe
3
O(Pz)
3
Mn]
[BAr
F
4
] (
1
-
[BAr
F
4
]
)
................................
................................
.........................
S1
2
Figure S3.
1
H NMR spectra (300 MHz) of [LFe
3
O(Pz)
3
Mn]
[OTf]
2
(
2
-
[OTf]
) and
[LFe
3
O(Pz)
3
Mn]
[BAr
F
4
]
2
(
2
-
[BAr
F
4
]
)
................................
................................
........................
S1
3
Figure S4.
19
F NMR spectra (300 MHz) of
[LFe
3
O(Pz)
3
Mn]
[OTf]
2
(
2
-
[OTf]
) and
[LFe
3
O(Pz)
3
Mn]
[
BAr
F
4
]
2
(
2
-
[BAr
F
4
]
)
................................
................................
........................
S1
3
Figure S5.
1
H NMR spectra (300
/500
MHz) of [LFe
3
O(Pz)
3
Mn]
[OTf]
3
(
3
-
[OTf]
) and
[LFe
3
O(Pz)
3
Mn]
[
BAr
F
4
]
3
(
3
-
[BAr
F
4
]
)
................................
................................
........................
S1
4
Figure
S6.
19
F NMR spectra (300 MHz) of
[LFe
3
O(Pz)
3
Mn]
[OTf]
3
(
3
-
[OTf]
) and
[LFe
3
O(Pz)
3
Mn]
[
BAr
F
4
]
3
(
3
-
[BAr
F
4
]
)
................................
................................
........................
S1
4
Figure S7.
1
H NMR spectra (500 MHz) of
1
-
[BAr
F
4
]
with various equivalents of H
2
O
..........
S1
5
Figure S8.
1
H NMR spectra (500 MHz) of
2
-
[BAr
F
4
]
with various equivalents of H
2
O
..........
S1
5
Figure S9.
1
H NMR spectra (500 MHz) of
3
-
[BAr
F
4
]
with various equivalents of H
2
O
...........
S1
6
Figure S10
.
1
H NMR spectra (500 MHz) of [LFe
3
O(Pz)
3
Mn(OH)] (
5
)
................................
....
S1
6
Figure S11.
1
H NMR spectra (300/500 MHz) of [LFe
3
O(Pz)
3
Mn(OH)][OTf]
(
6
-
[OTf]
)
and
[LFe
3
O(Pz)
3
Mn(OH)][
BAr
F
4
] (
6
-
[BAr
F
4
]
)
................................
................................
................
S1
7
Figure S12.
1
H NMR spectra (500 MHz) of [LFe
3
O(Pz)
3
Mn(OH)][
BAr
F
4
]
2
(
7
-
[BAr
F
4
]
)
........
S1
7
Fi
g
ure S13.
1
H NMR spectra (500 MHz) of
3
-
[BAr
F
4
]
with various equivalents of 2,6
-
dimethyl
-
pyridine
................................
................................
................................
................................
.......
S18
Table S1.
p
K
a
titration of
3
-
[BAr
F
4
]
with 2,6
-
dimethyl
-
pyridine
................................
..............
S18
Figure S1
4
.
1
H NMR spectra (500 MHz) of products of
1
-
[BAr
F
4
]
with 1 equivalent TEMPO
and 2,4,6
-
tri
-
tert
-
butylphenoxy radical
................................
................................
.......................
S1
9
Figure S1
5
.
1
H NMR spectra (500 MHz) of products of
2
-
[BAr
F
4
]
with 1 equivalent TEMPO
and 2,4,6
-
tri
-
tert
-
butylphenoxy radical
................................
................................
.......................
S1
9
Figure S1
6
.
1
H NMR spectra (500 MHz) of products of
3
-
[BAr
F
4
]
with 1 equivalent TEMPO
and 2,4,6
-
tri
-
tert
-
butylphenoxy radical
................................
................................
.......................
S
20
Figure S1
7
.
1
H NMR spectra (500 MHz) of products of
7
-
[BA
r
F
4
]
with 1 equivalent various
bases with and without 5 equivalents trimethylphosphine
................................
.........................
S2
1
Figure S1
8
.
31
P NMR spectra (120 MHz) of products of
7
-
[BAr
F
4
]
with 1 equivalent various
bases with and without 5 equivalents trimethylphosphine
................................
.........................
S
2
1
Figure S1
9
.
UV
-
Vis absorbance spectra of
1
-
[OTf]
................................
................................
..
S2
2
Figure S
20
.
UV
-
Vis absorbance spectra of
2
-
[OTf]
and
2
-
[BAr
F
4
]
................................
.........
S2
2
Figure S2
1
.
UV
-
Vis absorbance spectra of
3
-
[OTf]
and
3
-
[BAr
F
4
]
................................
.........
S2
3
Figure S2
2
.
UV
-
Vis absorbance spectra of
6
-
[BAr
F
4
]
................................
..............................
S2
3
Figure S2
3
.
UV
-
Vis absorbance spectra of
7
-
[BAr
F
4
]
................................
..............................
S2
4
Figure S2
4
.
UV
-
Vis absorbance spectra of
2
-
[BAr
F
4
]
with various equivalents
1,1,3,3
-
tetramethyl
-
2
-
phenylguanidine
and p
K
a
determination
................................
..............................
S2
4
Figure S2
5
.
Cyclic voltammogram of
2
-
[OTf]
in MeCN
................................
..........................
S2
5
Figure S2
6
.
Cyclic voltammogram of
2
-
[OTf]
in MeCN at various scan rates
........................
S2
5
Figure S2
7
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O]
................................
S2
6
Figure S2
8
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] at various scan rates
S2
6
S
3
Figure S2
9
.
Cyclic voltammogra
m of
6
-
[BAr
F
4
]
in THF [250 mM H
2
O]
................................
S2
7
Figure S
30
.
Cyclic voltammogram of
6
-
[BAr
F
4
]
in THF [250 mM H
2
O] at various scan rates
S2
7
Table S
2
.
Peak
-
to
-
peak separation and peak area ratio for CVs
2
-
[OTf]
,
2
-
[BAr
F
4
]
, and
6
-
[BAr
F
4
]
................................
................................
................................
................................
........
S2
8
Electrochemistry Data for Construction
the Potential
–
p
K
a
Diagram of
[LFe
3
O(Pz)
3
Mn(OH
x
)] Clusters
................................
................................
...............................
S2
9
Table S
3
.
Summary of observed
E
½
potentials with organic bases of various p
K
a
values
........
S2
9
Figure S3
1
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O]
with 2
-
methyl
-
aniline
................................
................................
................................
................................
..........
S
30
Figure S3
2
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 2
-
methyl
-
pyridine
................................
................................
................................
................................
.......
S
30
Figure S3
3
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 2,6
-
dimethyl
-
pyridine
................................
................................
................................
................................
.......
S3
1
Figure S3
4
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 2,4,6
-
trimethyl
-
pyridine
................................
................................
................................
................................
.......
S
3
1
Figure S3
5
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with triethylamine
..
S3
2
Figure S3
6
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 2
-
phenyl
-
1,1,3,3
-
tetramethylgaunidine
................................
................................
................................
...................
S
3
2
Figure S3
7
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 1,1,3,3
-
tetramethylguanidine
................................
................................
................................
...................
S3
3
Figure S3
8
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 1,8
-
diazabicyclo[5.4.0]undec
-
7
-
ene
................................
................................
................................
..
S3
3
Figure S3
9
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 7
-
methyl
-
1,5,7
-
triazabicyclo[4.4.0]dec
-
5
-
ene
................................
................................
................................
.....
S3
4
Figure S40
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 1,5,7
-
triazabicyclo[4.4.0]dec
-
5
-
ene
................................
................................
................................
.....
S3
4
Figure S4
1
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with
tert
-
butylimino
-
tri(pyrrolidino)phosphorane
................................
................................
................................
........
S3
5
Figure S4
2
.
Cyclic voltammogram of
2
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 1
-
ethyl
-
2,2,4,4,4
-
pentakis(dimethylamino)
2
λ
5
,4
λ
5
-
catenadi(phosphazene)
................................
..........................
S3
5
Figure S4
3
.
Cyclic voltammogram of
6
-
[BAr
F
4
]
in THF [2
50 mM H
2
O] with
tert
-
butylimino
-
tri(pyrrolidino)phosphorane
................................
................................
................................
........
S3
6
Figure S4
4
.
Cyclic voltammogram of
6
-
[BAr
F
4
]
in THF [250 mM H
2
O] with 1
-
ethyl
-
2,2,4,4,4
-
pentakis(dimethylamino)
2
λ
5
,4
λ
5
-
catenadi(phosphazene)
................................
..........................
S3
6
M
ö
ssbauer simulation details
................................
................................
................................
...
S3
7
Simulation
details for 1
-
[OTf]
................................
................................
................................
..
S3
7
Figure S46
.
Zero applied
field M
ö
ssbauer spectrum of
1
-
[OTf]
................................
...............
S3
8
Simulation details for 2
-
[OTf]
................................
................................
................................
..
S3
8
Figure S4
8
.
Zero applied
field M
ö
ssbauer spectrum of
2
-
[OTf]
................................
...............
S3
9
Simulation details for 3
-
[OTf]
................................
................................
................................
..
S3
9
Figure S4
9
.
Zero applied
field M
ö
ssbauer spectrum of
3
-
[OTf]
................................
...............
S
40
Simulation details for 1
-
[BAr
F
4
]
................................
................................
..............................
S
40
Figure S5
1
.
Zero applied
field M
ö
ssbauer spectrum of
1
-
[BAr
F
4
]
................................
...........
S
40
Simulation details for 2
-
[BAr
F
4
]
................................
................................
..............................
S
4
1
Figure S5
3
.
Zero applied
field M
ö
ssbauer spectrum of
2
-
[BAr
F
4
]
................................
...........
S
4
1
Simulation
details for 3
-
[BAr
F
4
]
................................
................................
..............................
S4
2
S
4
Figure S5
4
.
Zero applied
field M
ö
ssbauer spectrum of
3
-
[BAr
F
4
]
................................
...........
S4
2
Simulation details for 5
................................
................................
................................
.............
S4
2
Figure S5
6
.
Zero applied
field M
ö
ssbauer spectrum of
5
................................
..........................
S4
3
Simulation details for 6
-
[BAr
F
4
]
................................
................................
..............................
S4
4
Figure S5
8
.
Zero applied
field M
ö
ssbauer spectrum of
6
-
[BAr
F
4
]
................................
...........
S4
4
Simulation details for 7
-
[BAr
F
4
]
................................
................................
..............................
S4
5
Figure S
60
.
Zero applied
field M
ö
ssbauer spectrum of
7
-
[BAr
F
4
]
................................
...........
S4
5
Figure S6
1
.
Crystal structure and special refinement details of [LFe
3
O(Pz)
3
Mn][OTf] (
1
-
[OTf]
)
................................
................................
................................
................................
.........
S4
6
Figure S6
2
.
Crystal structure and special refinement details of [LFe
3
O(Pz)
3
Mn][OTf]
2
(
2
-
[OTf]
)
................................
................................
................................
................................
.........
S4
7
Figure S6
3
.
Crystal structure and special refinement details of [LFe
3
O(Pz)
3
Mn][OTf]
3
(
3
-
[OTf]
)
................................
................................
................................
................................
.........
S4
8
Figure S6
4
.
Crystal structure and special refinement details of [LFe
3
O(Pz)
3
Mn(OH
2
)][OTf]
2
(
2
-
[OTf]
(H
2
O)
)
................................
................................
................................
..............................
S4
9
Figure S6
5
.
Crystal structure and special refinement details of [LFe
3
O(Pz)
3
Mn(OH)][OTf] (
6
-
[OTf]
)
................................
................................
................................
................................
.........
S50
Table S
4
.
Crystal and refinement data for complexes
1
-
[OTf]
–
3
-
[OTf]
, 2
-
[OTf]
(H
2
O)
and
6
-
[OTf]
................................
................................
................................
................................
...........
S
5
1
References
................................
................................
................................
................................
..
S
5
2
S
5
Experimental Procedures
General Considerations
All reactions were performed at room temperature in an N
2
-
filled M. Braun glovebox or using
standard Schlenk techniques unless otherwise specified
; reactions of compounds in THF/H
2
O
mixtures were performed in an
N
2
-
filled
VAC
wetbox
. Glassware was oven dried at 140 ºC for at
least 2 h prior to use, and allowed to cool under vacuum.
[LFe
3
(OAc)(OTf)][OTf]
1
,
Mn(OTf)
2
•
2
MeCN
2
,
benzyl
potassium
3
,
iodos
o
benzene
4
,
silver
tetrakis[3,5
-
bis(trifluoromethyl)phenyl]borate bis
-
acetonitrile (Ag
[BAr
F
4
]
•
2
MeCN)
5
,
2,4,6
-
tri
-
tert
-
butylphenoxy
radical
(2,4,6
-
TBPR)
6
,
and
tetrapropylammnoium
tetrakis[3,5
-
bis(trifluoromethyl)p
henyl]borate ([
n
Pr
4
N][
BAr
F
4
])
7
were prepared according to literat
ure
procedures.
All organic solvents
were dried by sparging with nitrogen for at least 15 minutes, then
passing through a column of activated A2 alumina under positive N
2
pressure.
1
H and
19
F NMR
spectra were recorded on a Varian 300 MHz spectrometer.
1
H N
MR spectra in THF/C
6
D
6
were
recorded on a Varian 500 MHz spectrometer
using solvent suppression protocols
.
CD
3
CN,
CD
2
Cl
2
,
and C
6
D
6
were
purchased from Cambridge Isotope Laboratories, dried over calcium hydride,
degassed by three freeze
-
pump
-
thaw cycles, an
d vacuum transferred prior to use.
Physical Methods
M
össbauer measurements
. Zero field
57
Fe Mossbauer spectra were recorded at 80 K in constant
acceleration mode on a spectrometer from See Co (Edina, MN) equipped with an SVT
-
400 cryostat
(Janis, Wilmington, WA). The isomer shifts are relative to the centroid of an α
-
Fe foil signal at
room temp
erature. Samples were prepared by mixing polycrystalline material (20 mg) with boron
S
6
nitride in a cup fitted with screw cap or freezing a concentrated solution
in MeCN or THF
. The
data were fit to Lorentzian lineshapes using WMOSS (www.wmoss.org).
Electroc
hemical measurements
. CVs and SWVs were recorded with a Pine Instrument Company
AFCBP1 biopotentiostat with the AfterMath software package. All measurements were performed
in a three electrode cell, which consisted of glassy carbon (working; ø = 3.0 mm), s
ilver wire
(counter) and bare platinum wire (reference), in a N
2
filled M. Braun glovebox at RT.
Either t
he
ferrocene/ferrocinium (Fc/Fc
+
)
or decamethylferrocene/decamethylferrocinium (Fc
*
/Fc
*+
;
-
0.524
V vs Fc/Fc
+
in THF/250 mM H
2
O, under our experimental
conditions)
redox wave
s
were
used as
an internal standard for all measurements.
X
-
ray crystallography
. X
-
ray diffraction data was collected at 100 K on a Bruker PHOTON100
CMOS based diffractometer (microfocus sealed X
-
ray tube, Mo Kα (λ) = 0.71073 Å or Cu
Kα (λ)
= 1.54178 Å). All manipulations, including data collection, integration, and scaling, were carried
out using the Bruker APEXII software. Absorption corrections were applied using SADABS.
Structures were solved by direct methods using XS (incorporate
d into SHELXTL) and refined by
using ShelXL least squares on Olex2
-
1.2.7 to convergence. All non
-
hydrogen atoms were refined
using anisotropic displacement parameters. Hydrogen atoms were placed in idealized positions
and were refined using a riding model.
Due to the size of the compounds most crystals included
solvent
-
accessible voids that contained disordered solvent. In most cases the solvent could be
modeled satisfactorily.
S
7
Experimental
Procedures
Potassium pyrazolate (KPz)
.
1.09 g
(
16.0
mmol)
pyrazole was dissolved in
2 mL
THF. To this
stirring solution, a
10 mL
THF solution of benzyl potassium,
2.03 g
(
15.6
mmol)
, was added
dropwise; an off
-
white precipitate form
ed
. After stirring for 20 minutes, the reaction was
concentrated
to 10 mL
;
the sol
ids were collected on a glass frit
and washed with 2 mL THF
. The
white solid was dried completely under
vacuum
to obtain
1.37 g
(
83
% yield)
potassium pyrazolate.
Anal. calcd. (%) for
C
3
H
3
KN
2
: C.
33.94
; H,
2.85
; N,
26.39
. Found: C,
34.12
; H,
2.89
; N,
25.38
.
[LFe
3
O(Pz)
3
Mn][OTf]
2
(2
-
[OTf]
)
.
A
suspension
of
387
mg
(0.28
mmol)
[LFe
3
(OAc)(OTf)][OTf]
in
7 mL
THF was stirred with
98.4 mg (0.29 mmol)
Ca(OTf)
2
for an
hour before being frozen with LN
2
. To this mixture,
93.2 mg (0.88 mmol)
KPz was added in
thawing THF
(4 mL)
and stirred for 20 minutes
at room temperature
to obtain a dark red
-
orange
solution.
I
odosylbenzene
,
63.6 mg (0.29 mmol)
,
was added with
1 mL
THF and the reaction was
stirred for 90 minutes.
160 mg (0.37 mmol)
Mn(OTf)
2
• 2 MeCN solution in
2 mL
THF
was
then
added to the reaction. After 18 hours,
the reaction was concentrated to 10 mL and filtered over a
bed of celite;
the precipitate was dried
under vacuum
, extracted with
8 mL
DCM, and recrystallized
via vapor diffusion of Et
2
O into the
filtrate
. Dark green crystals of
2
-
[OTf]
were collected on a
glass
frit and dried
(
147 mg, 33% yield
)
.
Another 69 mg of
2
-
[OTf]
can be obtained by drying the
crude reaction filtrate, extracting with 6 mL DCM and recrystallizing via Et
2
O vapor diffusion
(46% overal
l yield).
X
-
ray diffraction quality crystals were obtained via oxidation of
[LFe
3
O(Pz)
3
Mn][OTf]
(
1
-
[OTf]
)
with 1 equivalent of AgBPh
4
; Et
2
O vapor diffusion into a
DCM
/THF
solution of the resulting
[LFe
3
O(Pz)
3
Mn][OTf]
[BPh
4
] produced crystals of suitable
quality.
1
H NMR (300 MHz, CD
3
CN):
δ
120.8 (br), 80.8 (br), 71.0, 70.1, 52.9, 52.3, 42.2, 28.0
(br), 15.5, 13.0, 10.4, 8.1 (br), 4.38, 3.01,
-
2.51 (br). UV
-
Vis (MeCN) [
ε
(M
-
1
cm
-
1
)]
241 nm
S
8
(6.53
10
4
)
, 368 nm (6.49
10
3
)
.
Anal. calcd. (%) for
C
68
H
48
F
6
Fe
3
Mn
N
12
O
10
S
2
: C. 51.25; H,
3.04; N, 10.55. Found: C, 50.81; H, 3.12; N, 10.18.
[LFe
3
O(Pz)
3
Mn][OTf]
(1
-
[OTf]
)
.
A suspension of
[LFe
3
O(Pz)
3
Mn][OTf]
2
(
2
-
[OTf]
;
91.5 mg,
0.057 mmol) in 2 mL THF was stirred as a THF solution of 10.9 mg CoCp
2
(0.058 mmol
) was
added. After 1 hour, the reaction was dried under vacuum. 4 mL DME was added to the purple
solid and stirred for 12 hours. The resulting purple precipitate was collected on a bed of celite
,
washed with 2 mL DME
, dried, and eluted with 2:1 THF/MeCN; c
rystals
of [LFe
3
O(Pz)
3
Mn][OTf]
(
1
-
[OTf]
)
were obtained by vapor diffusion of Et
2
O into this solution
(46.3 mg, 56% yield)
.
1
H
NMR (300 MHz, CD
3
CN):
δ
96.4 (br), 57.8, 55.5, 37.8 (br), 36.4, 34.3, 34.0, 25.2, 13.4, 13.0,
12.0, 11.4, 3.4, 2.6,
-
6.4 (br). UV
-
Vis (MeCN) [
ε
(M
-
1
cm
-
1
)]
250 nm (6.08
10
4
), 517 nm (3.72
10
3
)
.
Anal. calcd. (%) for
C
67
H
48
F
3
Fe
3
MnN
12
O
7
S: C, 55.70; H, 3.35; N, 11.63. Found: C, 55.36;
H, 3.58; N, 11.20.
[LFe
3
O(Pz)
3
Mn][OTf]
3
(3
-
[OTf]
)
.
9.2
mg (
0.036
mmol)
of AgOTf
in THF was added to a stirring
suspension
of
56.8
mg (
0.036
mmol)
[LFe
3
O(Pz)
3
Mn][OTf]
2
(
2
-
[OTf]
)
in THF. The resulting
brown suspension was pumped down after 30 minutes. The reaction was filtered over a celite
pad
using DCM and the solvent was removed under reduced pressure. Crystals of
[LFe
3
O(Pz)
3
Mn][OTf]
3
were obtained via vapor diffusion of Et
2
O into a concentrated
DCM/
Me
C
N solution of the crude
product,
57.4
mg (
92
% yield)
.
1
H NMR (300 MHz, CD
2
Cl
2
):
δ
162.2
(br), 118.9 (br), 81.2, 76.9, 74.4, 73.1, 45.7, 18.8 (br), 16.3, 9.5, 3.34, 1.,
-
6.5 (br).
UV
-
Vis
(MeCN) [
ε
(M
-
1
cm
-
1
)] 241 nm (7.84
10
4
), 411 nm (9.22
10
3
).
Anal. calcd. (%) for
C
69
H
48
F
9
Fe
3
MnN
12
O
13
S
3
: C, 47.55; H, 2.78; N, 9.64. Found: C, 47.57; H,
3.07; N, 9.21.
[LFe
3
O(Pz)
3
Mn]
(4)
. 4.1 mg (0.18 mmol) sodium metal was mixed ~6 g elemental mercury with
a pre
-
reduced stirbar. After 12 hours, a 5 mL THF suspension of
[LFe
3
O(Pz)
3
Mn][OTf]
2
(
2
-
[OTf]
;
S
9
114 mg, 0.07 mmol) was added to the Na/Hg amalgam. Over
4 hours, a blue precipitate formed;
this resulting suspension was decanted from the amalgam and filtered over a fine porosity
glass
frit. The solids were washed with 5 mL THF and dried under vacuum. The resulting blue material,
[LFe
3
O(Pz)
3
Mn]
(
78.1 mg; 84%
yield
),
is insoluble or unstable in most typical organic solvents.
Anal. calcd. (%) for
C
66
H
48
Fe
3
MnN
12
O
4
: C.
61.18
; H,
3.73
; N,
12.94
. Found: C,
60.44
; H,
3.82
;
N,
12.87
[LFe
3
O(Pz)
3
Mn][
BAr
F
4
]
(1
-
[BAr
F
4
]
)
.
14.0
mg (
0.013
mmol)
Ag
[BAr
F
4
]
•
2 MeCN in
2 mL
Et
2
O
was added to a stirring suspension of
[LFe
3
O(Pz)
3
Mn]
(
4
;
17.2
mg,
0.013
mmol)
; the blue
suspension change
d
to a purple solution. After
15 minutes, the solvent
wa
s removed under reduced
pressure.
3 mL
Et
2
O was added to the purple residue and filtered over a pad of celite. The filtrate
was dried to afford
[LFe
3
O(Pz)
3
Mn]
[BAr
F
4
]
as a purple solid
,
26.5
mg (
92
% yield)
.
1
H NMR (300
MHz, CD
3
CN) is identical to
[LFe
3
O(Pz)
3
Mn][
OTf
]
(
1
-
[OTf]
)
.
Anal. calcd. (%) for
C
98
H
60
B
F
24
Fe
3
MnN
12
O
4
: C. 5
4.52
; H,
2.80
; N,
7.79
. Found: C,
54.06
; H,
2.84
; N,
7.33
.
[LFe
3
O(Pz)
3
Mn
]
[BAr
F
4
]
2
(2
-
[BAr
F
4
]
)
.
45.0
mg (
0.043
mmol)
Ag
[BAr
F
4
]
•
2 MeCN in
2 mL
Et
2
O
was added to a stirring suspension of
[LFe
3
O(Pz)
3
Mn]
(
4
;
27
.6
mg,
0.021
mmol)
; the
blue
suspension change
d
to a brown
-
green solution. After 15 minutes, the solvent
wa
s removed under
reduced pressure.
3 mL
Et
2
O was added to the brown residue and filtered over a pad of celite.
6
mL b
enzene was added to the filtrate to produce an oily precipitate; after 30 minutes, the
supernatant was removed and the remaining brown
-
green
residue was
dried under reduced
pressure.
36.6
mg (
57
% yield)
of the
brown
-
green solid
,
2
-
[BAr
F
4
]
,
was obtained;
th
e
1
H NMR
(300 MHz, CD
3
CN) is identical to
[LFe
3
O(Pz)
3
Mn][
OTf
]
2
(
2
-
[OTf]
)
.
UV
-
Vis (THF/250 mM
H
2
O)
[
ε
(M
-
1
cm
-
1
)] 3
68
nm (5.1
1
10
3
).
Anal. calcd. (%) for C
130
H
72
B
2
F
48
Fe
3
MnN
12
O
4
: C.
51.67
;
H,
2.40
; N,
5.56
. Found: C,
51.38
; H,
2.56
; N,
5.46
.