Metal complexes of N-p-nitrobenzoylamido-meso-tetraphenylporphyrin: cis-acetato-N-p-nitrobenzoylimido-meso-tetraphenylporphyrinatothallium(III) and N-p-nitrobenzoylimido-meso-tetraphenylporphyrinatonickel(II)

Article abstract of DOI:10.1021/ic000823p

This work for the first time reports X-ray crystals of two metal complexes, i.e., a four-coordinate, bridged nickel(II) porphyrin complex, Ni(N-p-NCOC₆H₄NO₂-tpp) (1) with a Ni^II-N-(p-COC₆H₄NO₂)-N (or Ni^II-NNB-N) linkage, and a cisoid six-coordinate, bridged thallium (III) porphyrin complex, Tl(N-p-NCOC₆H₄NO₂-tpp)(OAc) (3) with an Tl^III-N-(p-COC₆H₄NO₂)-N (or Tl^III-NNB-N) linkage. Compound 1 is a distorted square planar, whereas compound 3 is a distorted square-based pyramid in which the apical site is occupied by a chelating bidentate OAc^- group.

Full text of DOI:10.1021/ic000823p

Inorg. Chem. 2001, 40, 2905-2909
2905
Notes
) 1.025 Å),6 the relative position of OAc- and p-nitrobenzoyl
(NB) group coordinated to the Tl atom might lead to a cis
configuration in 3. In addition, the acetato exchange of Tl(N-
NTs-tpp)(OAc) observed in CD2Cl2 prompted us to investigate
a similar intermolecular exchange for complex 3 in THF-d8 by
1H and 13C dynamic NMR method.5
Metal Complexes of N-p-Nitrobenzoylamido-
meso-tetraphenylporphyrin:
cis-Acetato-N-p-nitrobenzoylimido-meso-
tetraphenylporphyrinatothallium(III) and
N-p-Nitrobenzoylimido-meso-
tetraphenylporphyrinatonickel(II)
Experimental Section
Ni(N-p-NCOC6H4NO2-tpp) (1).2 Compound 1 was dissolved in
CH2Cl2 and layered with MeOH, and thus the purple crystals of 1 were
obtained for single-crystal X-ray analysis. 1H NMR (599.95 MHz,
Chen-Shing Chang, Ching-Huei Chen, Yu-I Li,
Bing-Chuang Liau, Bao-Tsan Ko,
Shanmugham Elango, and Jyh-Horung Chen*
3
CDCl3, 25 °C): δ 8.99 [d, Hâ(18,39), J(H-H) ) 4.8 Hz], Hâ(a,b)
Department of Chemistry, National Chung-Hsing University,
Taichung 40227, Taiwan, R.O.C.
represents the two equivalent â-pyrrole protons attached to carbons a
3
and b, respectively; 8.72[s, Hâ(28,29)]; 8.68 [d, Hâ(17,40), J(H-H)
) 4.8 Hz]; 7.66-8.14 (m, phenyl protons); 7.57 [s, Hâ(50,51)]; 6.80
3
[d, HNB(4,6) or NB-H3,5, J(H-H) ) 9.0 Hz], HNB(c,d) represents the
Lian-Pin Hwang
two equivalent protons attached to carbons c and d of p-nitrobenzoyl
3
Department of Chemistry, National Taiwan University and
Institute of Atomic and Molecular Sciences,
(NB) group, respectively; 4.93 [d, HNB(3,7) or NB-H2,6, J(H-H) )
9.0 Hz].
Academia Sinica, Taipei 10764, Taiwan, R.O.C.
Tl(N-p-NCOC6H4NO2-tpp)(OAc) (3). A mixture of N-p-HNCOC6H4-
NO2-Htpp (50 mg, 0.0068 mmol) in CH2Cl2(10 cm3) and Tl(OAc)3
(40 mg, 0.12 mmol) in MeOH (2.5 cm3) was refluxed for 1 h. After
concentrating, the residue was dissolved in CHCl3, dried with anhydrous
Na2SO4, and filtered. The filtrate was concentrated and recrystallized
from CH2Cl2-MeOH [1:5 (v/v)] yielding purple solid of 3 (39 mg,
0.037 mmol, 55%) which was again dissolved in CH2Cl2-ether [1:1
(v/v)] and layered with MeOH to get purple crystals for single-crystal
ReceiVed July 24, 2000
Introduction
Metalloporphyrins with a bridged structure between the
central metal and one of the four pyrrole nitrogens have drawn
much attention in recent times. Bridged metalloporphyrins with
only metal-NTs-N linkages (metal ) Zn,1 Ni,2 Fe,3 Hg,4 Ga,5
Tl,5 Ts ) tosyl) have so far been reported. Callot et al.2 reported
1
X-ray analysis. H NMR (599.95 MHz, CD2Cl2, 25 °C): δ 9.32 [d d,
4
3
Hâ(8,17), J(Tl-H) ) 20 Hz and J(H-H) ) 4.5 Hz]; 8.96 [dd, Hâ-
4
3
(7,18), J(Tl-H) ) 14 Hz and J(H-H) ) 4.8 Hz]; 8.63 [d, Hâ(12,-
13), 4J(Tl-H) ) 75.3 Hz]; 7.20 [d, Hâ(2,3), 5J(Tl-H) ) 6 Hz]; 8.50(m),
8.22 (m) and 8.12 (m) for phenyl ortho protons (o-H); 7.75-7.89 (m)
for phenyl meta and para protons (m-, p-H); 7.04 [d, HNB(48,50) or
1
the synthesis and H NMR investigation of the metalation of
N-p-nitrobenzoylamido-meso-tetraphenylporphyrin
[N-p-
3
3
HNCOC6H4NO2-Htpp] (tpp ) dianion of meso-tetraphenylpor-
phyrin) leading to mononuclear complexes of N-p-nitroben-
NB-H3,5, J(H-H) ) 8.4 Hz], 5.25 [t, HNB(47,51) or NB-H2,6, J(H-
H) ) 8.4 Hz]; 0.17 (s, OAc). MS, m/z (assignment, rel intensity): 1040
([Tl(N-p-NCOC6H4NO2-tpp)(OAc)]+, 1.65), 981([Tl(N-p-NCOC6H4-
NO2-tpp)]+, 42.89), 817 ([Tl(tpp) + H]+, 23.28), 779([H-N-p-NCOC6H4-
NO2-Htpp)]+, 20.88), 614 (Htpp+, 16.99), 205 (205Tl+, 64.34), 203
zoylimido-meso-tetraphenylporphyrinatonickel(II)
Ni(N-p-
NCOC6H4NO2-tpp) (1) and N-p-nitrobenzoylimido-meso-
tetraphenylporphyrinatocopper(II) Cu(N-p-NCOC6H4NO2-tpp)
(2).
(
203Tl+, 26.22). UV/visible spectrum, λ (nm)[ꢀ × 10-3 (M-1 cm-1)] in
CH2Cl2: 325 (13.6), 432 (124.0), 547 (6.2), 585 (6.8), 639 (5.2).
Spectroscopy. Proton and 13C NMR spectra were recorded at 299.95
(or 599.95) and 75.43 (or 150.87) MHz, respectively, on Varian VXR-
300 (or Varian Unity Inova-600) spectrometers locked on deuterated
solvent and referenced to the solvent peak. Proton NMR is relative to
CD2Cl2, CDCl3, or THF-d8 at δ ) 5.30, 7.24, or 1.73 (the upfield
resonance) and 13C NMR to the center line of CD2Cl2, CDCl3, or THF-
d8 at δ ) 53.6, 77.0, or 25.3 (the upfield resonance). Next, the
temperature of the spectrometer probe was calibrated by the shift
There are no X-ray structural data available for the metal
ion [M(II) and M(III)] complexes of HNCOC6H4NO2-Htpp. In
this paper, we report the X-ray structural determination of the
title compound Ni(N-p-NCOC6H4NO2-tpp) (1), and we also
present the results upon replacing Ni(II) with Tl(III) in 1 forming
a new compound (3). This replacement increases the coodination
number (CN) from 4 for 1 to 6 for cis-acetato-N-p-nitroben-
zoylimido-meso-tetraphenylporphyrinatothallium(III) Tl(N-p-
NCOC6H4NO2-tpp)(OAc) (3). The presence of acetate ligands
in 3 plays a role in somewhat artificially increasing the
coordination number. Because of the larger size of the Tl3+ (rion
difference of methanol resonance in the H NMR spectrum. H-13C
COSY was used to correlate protons and carbon through one-bond
coupling and HMBC (heteronuclear multiple bond coherence) for two-
and three-bond proton-carbon coupling.
1
1
The positive-ion fast atom bombardment mass spectrum (FAB MS)
was obtained in a nitrobenzyl alcohol (NBA) matrix using a JEOL JMS-
SX/SX 102A mass spectrometer. UV/visible spectra were recorded at
25 °C on a HITACHI U-3210 spectrophotometer.
Crystallography. Table 1 presents the crystal data as well as other
information for Ni(N-p-NCOC6H4NO2-tpp) (1) and Tl(N-p-NCOC6H4-
NO2-tpp)(OAc) (3). Measurements were taken on a Siemens SMART
* To whom correspondence should be addressed.
(1) Li, Y. I.; Chang, C. S.; Tung, J. Y.; Tsai, C. H.; Chen, J. H.; Liao, F.
L.; Wang, S. L. Polyhedron 2000, 19, 413.
(2) Callot, H. J.; Chevrier, B.; Weiss, R. J. Am. Chem. Soc. 1978, 100,
4733.
(3) Mahy, J. P.; Battioni, P.; Bedi, G.; Mansuy, D.; Fishcher, J.; Weiss,
R.; Morgenstern-Badarau, I. Inorg. Chem. 1988, 27, 353.
(4) Callot, H. J.; Chevrier, B.; Weiss, R. J. Am. Chem. Soc. 1979, 101,
7729.
(5) Tung, J. Y.; Jang, J. I.; Lin, C. C.; Chen, J. H.; Hwang, L. P. Inorg.
Chem. 2000, 39, 1106.
(6) Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry, 4th
ed.; Harper Collins College: New York, 1993; p 114.
10.1021/ic000823p CCC: $20.00 © 2001 American Chemical Society
Published on Web 05/11/2001

2906 Inorganic Chemistry, Vol. 40, No. 12, 2001
Table 1. Crystal Data for (1) and (3)
Notes
empirical formula
fw
space group
cryst syst
a, Å
C51H32N6NiO3 (1)
835.54
C2/c
monoclinic
22.5402(11)
15.7500(8)
22.6703(11)
90
96.8100(10)
90
7991.4(7)
8
C53H35N6O5Tl (3)
1040.24
P21/c
monoclinic
12.5257(14)
24.360(3)
14.5349(17)
90
101.124(2)
90
4351.7(9)
4
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
F000
3456
1.389
5.40
1.058
2064
1.588
37.70
0.864
Dcalcd, g cm-3
µ(Mo KR), cm-1
S
cryst size, mm3
2θmax, deg
T, K
0.8 × 0.3 × 0.2
0.11 × 0.26 × 0.28
56.58
52.06
295(2)
293(2)
no. of reflns measd
no. of reflns obsd
Ra (%)
23 412
8921 (I > 2σ(I))
4.21
24 296
8546 (I > 2σ(I))
4.45
Rwb (%)
11.25
11.47
a R ) [∑||Fo| - |Fc||/∑|Fo|]. b Rw ) [∑w(||Fo| - |Fc||)2/∑w(|Fo|)2]1/2
;
w ) A/(σ2Fo + BFo ).
2
Table 2. Selected Bond Distances (Å) and Angles (deg) for
Compounds 1 and 3
Ni(N-p-NCOC6H4NO2-tpp) (1)
Distances
Ni(1)-N(1)
Ni(1)-N(3)
Ni(1)-N(4)
Ni(1)-N(5)
1.843(2)
1.937(2)
1.874(2)
1.940(2)
N(1)-C(1)
C(1)-O(1)
C(1)-C(2)
N(1)-N(2)
1.343(2)
1.227(2)
1.504(3)
1.390(2)
Angles
N(3)-Ni(1)-N(5)
N(3)-Ni(1)-N(1)
N(3)-Ni(1)-N(4)
N(1)-Ni(1)-N(5)
N(1)-Ni(1)-N(4)
166.39(7)
86.92(7)
93.87(7)
88.34(7)
164.18(7)
Ni(1)-N(1)-N(2)
Ni(1)-N(1)-C(1)
N(1)-C(1)-O(1)
N(1)-C(1)-C(2)
N(4)-Ni(1)-N(5)
104.8(1)
141.2(1)
123.9(2)
116.4(2)
94.16(7)
Tl(N-p-NCOC6H4NO2-tpp)(OAc) (3)
Distances
Tl-O(4)
Tl-O(5)
Tl-N(2)
Tl-N(3)
Tl-N(4)
Tl-N(5)
2.356(5)
2.365(4)
2.337(5)
2.157(4)
2.343(4)
2.147(5)
N(5)-N(1)
O(4)-C(52)
O(5)-C(52)
C(52)-C(53)
N(5)-C(45)
C(45)-O(1)
1.409(6)
1.250(8)
1.248(8)
1.496(9)
1.345(7)
1.225(7)
Figure 1. Molecular configuration and atom-labeling scheme for (a)
Ni(N-p-NCOC6H4NO2-tpp) (1) and (b) Tl(N-p-NCOC6H4NO2-tpp)-
(OAc) (3), with ellipsoids drawn at 30% probability. Hydrogen atoms
for both compounds are omitted for clarity.
Angles
O(4)-Tl-O(5)
O(4)-Tl-N(2)
O(4)-Tl-N(3)
O(4)-Tl-N(4)
O(4)-Tl-N(5)
O(5)-Tl-N(2)
O(5)-Tl-N(3)
54.9(2)
146.9(2)
93.2(2)
91.3(2)
112.5(2)
93.1(2)
95.4(2)
Tl-O(4)-C(52)
Tl-O(5)-C(52)
O(4)-C(52)-O(5)
Tl-N(5)-C(45)
Tl-N(5)-N(1)
O(5)-Tl-N(4)
O(5)-Tl-N(5)
92.0(4)
91.6(4)
121.3(6)
133.1(4)
106.6(3)
146.0(2)
110.8(2)
tpp) (1) and in Figure 1b for Tl(N-p-NCOC6H4NO2-tpp)(OAc)
(3). Both these structures, four-coordinate nickel of 1 and six-
coordinate thallium of 3, have bonding with three nitrogen atoms
of the porphyrins and one extra nitrogen atom of the nitrene
fragment in common, but compound 3 has in addition one more
chelating bidentate OAc- ligand in the axial site. In 1 and 3 it
appears that the N-p-nitrobenzoyl (NB) moiety is inserted into
the Ni-N bond of meso-tetraphenylporphyrinatonickel(II), Ni-
(tpp),7 and the Tl-N bond of acetato(meso-tetraphenylporphy-
rinato)thallium(III) Tl(tpp)(OAc).8 The unusual metal-ligand
bond distances, i.e., from Ni(II) and Tl(III) atoms to the ligand,
and the angles are summarized in Table 2. The interaction of
the acetate with thallium is chelating bidentate. This kind of
CCD diffractometer using monochromatized Mo KR radiation (λ )
0.710 73 Å). The empirical absorption corrections were made for 1.
The structures were solved by direct methods (SHELXTL PLUS) and
refined by the full-matrix least-squares method. All non-hydrogen atoms
were refined with anisotropic thermal parameters, whereas all hydrogen
atom positions were calculated using a riding model and were included
in the structure factor calculation. Table 2 lists selected bond distances
and angles for both complexes.
Results and Discussion
Molecular Structures of 1 and 3. The X-ray framework is
depicted in Figure 1a for the complex Ni(N-p-NCOC6H4NO2-
(7) Marsh, D. F.; Mink, L. M. J. Chem. Educ. 1996, 73, 1188.

Notes
Inorganic Chemistry, Vol. 40, No. 12, 2001 2907
bidentate interaction was previously observed for Tl(N-NTs-
tpp)(OAc) with Tl-O(1) ) 2.410(8) Å and Tl-O(2) ) 2.292-
(9) Å.5
The geometry around Ni2+ is a distorted square planar,
whereas for Tl3+ it is described as a distorted square-based
pyramid in which the apical site is occupied by a chelating
bidentate OAc- group. The pyrrole nitrogens N(2) and N(1)
are no longer bonded to the nickel and thallium as indicated by
their longer internuclear distances, 2.576 Å for Ni(1)‚‚‚N(2) and
2.886 Å for Tl‚‚‚N(1). The Ni(1)-N(4) bond trans to the N(1)
position in compound 1 is slightly shorter than the other two
Ni(1)-N bond distances [i.e., 1.874(2) Å for Ni(1)-N(4),
compared to 1.937(2) Å for Ni(1)-N(3) and 1.940(2) Å for
Ni(1)-N(5)]. Similarly, the Tl-N(3) bond in compound 3 is
also shorter than the other two Tl-N distances [2.157(4) Å for
Tl-N(3) vs 2.343(4) Å for Tl-N(4) and 2.337(5) Å for Tl-
N(2)]. Figure 2 shows the actual porphyrin skeleton of 1 and 3.
We adopt the plane of three strongly bound pyrrole nitrogen
atoms [i.e., N(3), N(4), and N(5) for 1 and N(2), N(3), and N(4)
for 3] as a reference plane 3N. Because of the larger size of the
Tl3+, Tl and N(5) lie 1.15 and 1.25 Å, respectively, above the
3N plane in 3, compared to 0.17 Å for Ni and 0.83 Å for N(1)
in 1 (Figure 2). For the same reason, i.e., due to the larger size
of the Tl3+, the chelating bidentate acetate in 3 is cis to the NB
group with O(4) and O(5) being located separately at 2.97 and
3.05 Å out of the 3N plane. The porphyrin macrocycle is indeed
distorted because of the presence of the NB group (Figure 2).
Thus, the N(2) and N(1) pyrrole rings bearing the NB group
would be deviated mostly from the 3N plane and oriented
separately in a dihedral angle of 43.8° and of 49.4°, whereas
small angles of 11.4°, 4.5°, and 6.8° occur with N(3), N(4),
and N(5) pyrroles for compound 1 and 9.9°, 6.5°, and 8.3° with
N(2), N(3), and N(4) pyrroles for compound 3, In compound
1, such a large deviation from planarity for the N(2) pyrrole is
also reflected by observing a 12-19 ppm upfield shift of the
Câ (C50, C51) at 118.4 ppm compared to 137.8 ppm for Câ
(C18, C39), 133.8 ppm for Câ (C28, C29), and 130.3 ppm for
Câ (C17, C40) (Figure S1a in Supporting Information). In
compound 3, a similar deviation is also found for the N(1)
pyrrole by observing a 17-21 ppm upfield shift of the Câ (C2,
C3) at 115.2 ppm compared to 132.3 for Câ (C12, C13), 133.9
ppm for Câ (C7, C18), and 136.0 ppm for Câ (C8, C17). Similar
kinds of upfield shifts of Câ resonances due to the nonplanarity
of porphyrin were also observed with a magnitude of 15-17
ppm for Zn(N-NTs-tpp),1 16-21 ppm for Tl(N-NTs-tpp)(OAc),5
and 5.6-7.0 ppm for Tl(N-Me-tpp)(OAc)2.9
Figure 2. Diagram of the porphyrinato core (C20N4, M, NB, and OAc-)
of (a) compound 1 and (b) compound 3. The values represent the
displacements (in angstroms) of the atoms from the mean 3N plane
[i.e., N(3)-N(5) for 1 and N(2)-N(4) for 3].
The pyrrole ring nitrogens N(2) and N(1) are in fact inclined
toward the Ni and Tl atoms, in 1 and 3, respectively. These
distortions make the distances between opposite pyrrole nitrogen
atoms unusual. The normal diameter of the “hole” in an
undistorted metalloporphyrin complex has been estimated to be
4.02 Å.10 The N(2)‚‚‚N(4) distance of 4.409 Å in 1 and the
N(1)‚‚‚N(3) distance of 4.439 Å in 3 are unusually long, which
is caused by the large deviations of the N(2) pyrrole in 1 and
N(1) pyrrole in 3 from the 3N plane, respectively. Also affected
by the distortion are the N(3)‚‚‚N(5) distance of 3.849 Å in 1
and the N(2)‚‚‚N(4) distance of 4.039 Å in 3. Hence, in 3, the
thallium(III) atom is bound in an expanded porphyrinato (4N)
core [i.e., the plane N(1)-N(4)]. The plane (P) defined by Ni-
(1), N(1), N(2), and C(1) in 1, and by Tl, N(5), N(1), and C(45)
in 3 is almost perpendicular to the 3N plane with a angle of
87.3° for 1 and 81.4° for 3. The p-nitrobenzoyl group (NB)
[i.e., the plane for NB in 1 is C(2)-C(7) and for 3 it is C(46)-
C(51)] is bonded to N(1) in 1 and N(5) in 3 so that it lies above
the macrocycle, orienting in a dihedral angle of 85.6° and 68.2°
with the 3N plane in 1 and 3, respectively. The dihedral angles
between the mean plane of the skeleton (3N) and the planes of
the phenyl groups are 59.8° [C(13)], 69.7° [C(24)], 64.0°
[C(35)], and 36.9° [C(46)] for 1 and 44.0° [C(24)], 78.7°
[C(30)], 87.4° [C(36)], and 42.2° [C(42)] for 3.
The comparison made for Ni(II) derivatives of carbene,
nitrene, and oxygen inserted complexes displays severe non-
planarity. Ni(1) and N(1) lie 0.23 and 1.01 Å above the mean
plane of the four pyrrole nitrogens N(2)-N(5) (i.e., 4N plane)
in 1 compared to 0.19 Å for Ni and 1.04 Å for the extra carbon
atom C1 of the ethoxycarbonylcarbene fragment inserted into
(8) Suen, S. C.; Lee, W. B.; Hong, F. E.; Jong, T. T.; Chen, J. H.; Hwang,
L. P. Polyhedron 1992, 11, 3025.
(9) Tung, J. Y.; Chen, J. H.; Liao, F. L.; Wang, S. L.; Hwang, L. P. Inorg.
Chem. 2000, 39, 2120.
(10) Collins, D. M.; Hoard, J. L. J. Am. Chem. Soc. 1970, 92, 3761.

2908 Inorganic Chemistry, Vol. 40, No. 12, 2001
Notes
a Ni-N bond of nickel(II) meso-tetraphenylporphine.11 Ad-
ditionally, Ni(1) and N(1) lie 0.17 and 0.83 Å above the 3N
plane in 1 compared to 0.05 Å for Ni and 0.65 Å for O(1) in
nickel(II) octaethylporphyrin N-oxide.12 The nonplanarity is
further reflected in the angle between the 4N plane and the N(2)
pyrrole ring in 1. This angle is 39.9° for 1 compared to 46.4°
for the N(4) pyrrole ring in the complex with an ethoxycarbo-
nylcarbene moiety inserted into a Ni-N bond of nickel(II) meso-
tetraphenylporphine.11 Furthermore, the angle between the plane
of the N(2) pyrrole ring and the 3N plane is 43.8° in 1, while
that between the plane of N-oxide pyrrole and the plane of the
other three pyrrole and the two connecting meso carbons is 38.3°
in nickel(II) octaethylporphyrin N-oxide.12
separation of 18 Hz at δ ) 0.034 ppm at -110 °C. As the
exchange of OAc- within 3 is reversible, the results at 599.95
MHz confirm the separation as a coupling of 4J (Tl-H) rather
than a chemical shift difference. The most likely cause of loss
of coupling is due to reversible dissociation of acetate
T1(N-p-NCOC6H4NO2-tpp)(OAc) h
T1(N-p-NCOC6H4NO2-tpp)+ + OAc- (1)
with a small dissociation constant.14 Such a scenario would lead
to a change in the chemical shift with temperature and no
detectable free OAc- and Tl(N-p-NCOC6H4NO2-tpp)+ at low
temperature, but would lead to the loss of coupling between
acetate and thallium at higher temperature. The chemical shift
in the high-temperature limit is the average of the two species
[i.e., Tl(N-p-NCOC6H4NO2-tpp)(OAc) and OAc-] in eq 1
weighted by their concentration. A comparison of observed and
1H and 13C NMR for Ni(N-p-NCOC6H4NO2-tpp) (1) and
Tl(N-p-NCOC6H4NO2-tpp)(OAc) (3) in CDCl3 and CD2Cl2
(Figure S1 in Supporting Information). In solution, the
molecule has effective Cs symmetry with a mirror plane running
through the N(4)-Ni(1)-N(1)-N(2) unit for 1 or the N(3)-
Tl-N(5)-N(1) unit for 3. There are four distinct â-pyrrole
protons Hâ, four â-pyrrole carbons Câ, four R-pyrrole carbons
CR, two different meso carbons Cmeso, and two phenyl-C1
carbons for both complexes. The NMR study of 3 showed four
different types of Tl-H coupling constants for Hâ (Figure S1b
in Supporting Information). The doublet at 8.63 ppm is assigned
as Hâ(12,13) with 4J(Tl-H) ) 75.3 Hz, and the doublet at 7.20
computed spectra yields ∆Gq
) 36.7 kJ/mol. At 25 °C,
175
intermolecular exchange of the OAc- group is rapid as indicated
by the appearance of singlet signals due to carbonyl carbons at
175.1 ppm and methyl carbons at 18.5 ppm. At -110 °C, the
rate of intermolecular exchange of OAc- for 3 in THF-d8 is
slow. Hence, at this temperature, the methyl and carbonyl
carbons of OAc- are observed at 18.9 ppm [with J(Tl-C) )
3
227 Hz] and 175.9 ppm [with 2J(Tl-C) ) 211 Hz] as doublets,
respectively. These 13C resonances are quite close to that of
Tl(N-NTs-tpp)(OAc) in which the two corresponding carbons
were also observed, in CD2Cl2 at -110 °C, at 18.5 ppm [with
5
ppm is due to Hâ(2,3) with J(Tl-H) ) 6 Hz. The doublet of
4
a doublet at 9.32 ppm is due to Hâ(8,17) with J(Tl-H) ) 20
3
Hz and J(H-H) ) 4.5 Hz, and the doublet of a doublet at
8.96 ppm is due to Hâ(7,18) with 4J(Tl-H) ) 14 Hz and 3J(H-
H) ) 4.8 Hz. Likewise, there were also four different types of
Tl-13C coupling constants for Câ. The doublet at 132.3 ppm is
3J(Tl-C) ) 220 Hz] and 176.3 ppm [with J(Tl-C) ) 205
2
Hz] as doublets.5
At low temperature, some differences in OAc- resonances
were observed. However, the differences for the 1H resonances
of pyrrole protons Hâ, meta and para protons in porphyrin, and
the resonances of NB-H2,6 and NB-H3,5 in N-p-nitrobenzoyla-
mido were small for 3 in THF-d8 at 25 and -110 °C. However,
for ortho protons, at -110 °C, the rotation of phenyl group along
the C1-Cmeso bond in 3 is slow, which is evident from the
appearance of the four broad singlets at 8.94, 8.31, 8.17, and
8.06 ppm due to four different ortho protons of the aromatic
ring. At 25 °C, this rotation becomes more rapid, and hence
the 1H resonances for ortho protons of 3 were observed in THF-
d8 with two sets of doublet and one broad singlet: one doublet
3
due to Câ (C12, C13) with J(Tl-13C) ) 167 Hz, and the
3
doublet at 136.0 ppm is due to Câ (C8, C17) with J(Tl-13C)
) 39 Hz. The singlet at 133.9 ppm is due to Câ (C7, C18) with
3J(Tl-13C) being unobserved and the doublet at 115.2 ppm is
4
1
due to Câ (C2, C3) with J(Tl-13C) ) 82 Hz. The H NMR
spectra reveal that the aromatic protons of the NB group appear
as a doublet at 7.04 (NB-H3,5) and triplet at 5.25 ppm (NB-
H2,6) for 3 (Figure S1b in Supporting Information) and at 6.80
(d) and 4.93 (t) ppm for 1. All p-nitrobenzoylimido and acetato
protons are shifted upfield compared to their counterparts in
free N-p-HNC6H4NO2-Htpp and OAc-; such a shift is presum-
ably attributed to the porphyrin ring current effect. The ring
current effect indicates that the NB groups are bonded to Ni(1)
in 1 and to Tl in 3. This bonding argument is further supported
by the result that in 13C NMR the NB-C1 [i.e., C(46)] and the
3
at 8.22 ppm with J(H-H) ) 6 Hz and the other doublet at
3
8.13 ppm with J(H-H) ) 7.2 Hz, and one broad singlet at
8.54 ppm.
3
Though we did not undertake the experiment to observe the
OAc- exchange with O13Ac-, PrO-, or PhCOO-, a similar kind
of intermolecular OAc- (or benzoato) exchange was also
C(45) in 3 were observed at 138.9 ppm with J(Tl-C) ) 22
2
Hz and at 168.2 ppm with J(Tl-C) ) 599 Hz, respectively.
Because C(45) in 3 is bonded to an electronegative atom O(1),
the 2p-electron density around carbon C(45) is reduced. This
removal of electron density increases both the effective nuclear
charge and the s-electron density for the C(45) nucleus, and
9
observed for Tl(N-Me-tpp)(OAc)2 in THF-d8 [or for Tl(tmp-
p)(PhCOO) in CD2Cl2 solvent].15 From the above analysis, the
exchange of OAc- in 3 should be an intermolecular process.
To date, other anions such as Cl-, N3-, and MeO- cannot
behave as ligands of the cationic thallium complex Tl(N-p-
NCOC6H4NO2-tpp)+.
2
therefore J(Tl-C) coupling constants increase from 65 ( 24
Hz for CR to 599 Hz for C(45) in 3.13
Dynamic NMR of 3 in THF-d8. Upon cooling of a 3.6 ×
10-3 M THF-d8 solution of 3 (Figure S2 in Supporting
Information), the methyl proton signals of OAc- are a single
peak at 25 °C (δ ) 0.16 ppm), first broadened (coalescence
temperature Tc ) -98 °C) and then split into two peaks with a
The properties of complex 1 in the solid state are similar to
those properties in solution. However, for 3, the properties in
the solid state are different from those in solution, because
complex 3 dissociates into Tl(N-p-NCOC6H4NO2-tpp)+ and
OAc- in THF solution.
(11) Chevrier, B.; Weiss, R. J. Am. Chem. Soc. 1976, 98, 2985.
(12) Balch, A. L.; Chan, Y. W.; Olmstead, M. M. J. Am. Chem. Soc. 1985,
107, 6510.
(13) Wehri, F. W.; Marchand, A. P.; Wehrli, S. Interpretation of Carbon-
13 NMR Spectra, 2nd ed.; John Wiley & Sons: New York, 1989; pp
65-66.
(14) Jenson, J. P.; Muetterties, E. L. In Dynamic Nuclear Magnetic
Resonance Spectroscopy; Jackman, L. M., Cotton, F. A., Eds.;
Academic Press: New York, 1975; pp 299-304.
(15) Sheu, Y. H.; Hong, T. N.; Chen, J. H.; Liao, F. L.; Wang. S. L.; Wang,
S. S.; Yang, C. T. Polyhedron 1997, 16, 1621.

Notes
Inorganic Chemistry, Vol. 40, No. 12, 2001 2909
Conclusions
Acknowledgment. The financial support from the National
Science Council of the R.O.C. under Grant NSC 89-2113-M-
005-023 is gratefully acknowledged.
We have investigated for the first time the two diamagnetic,
mononuclear, and bridged metal complexes of N-p-nitroben-
zoylamido-meso-tetraphenylporphyrin having M-N-(p-COC6H4-
NO2)-N [or M-N-NB-N, M ) Ni(II), Tl(III)] linkage, and
their X-ray structures are analyzed. Excepting the phenyl protons
and carbons, the unambiguous assignments of 1H and 13C NMR
data for 1 in CDCl3 and 3 in CD2Cl2 are reported in this work.
Supporting Information Available: 13C NMR spectrum (Figure
1
S1) and its assignment for 1, H NMR spectrum of 3 (Figure S1) and
1
its 13C NMR data and H NMR spectra for the acetato protons of 3
(Figure S2) at various temperatures; X-ray crystallographic files in CIF
format for compounds 1 and 3. This material is available free of charge
via the Internet at http://pubs.acs.org.
1
Dynamic H and 13C NMR spectra of the acetato group in 3
reveal that this group undergoes an intermolecular exchange
with a free energy of activation, ∆Gq
) 36.7 kJ/mol.
IC000823P
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