Metal complexes of 2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrin: M(2-NCH2C6H5NCTPP) (M = Ni2+, Pd2+) and Mn(2-NCH2C6H5NCTPP)Br (NCTPP = N-confused 5,10,15,20-tetraphenyl porphyrinate)

Article abstract of DOI:10.1016/j.poly.2011.09.034

The crystal structures of (2-aza-2-benzyl-5,10,15,20-tetraphenyl-21- carbaporphyrinato-N,N′,N″) nickel(II) methylene chloride solvate [Ni(2-NCH₂C₆H₅NCTPP); 4], (2-aza-2-benzyl-5,10, 15,20-tetraphenyl-21-carbaporphyrinato-N,N′,N″) palladium(II) [Pd(2-NCH₂C₆H₅NCTPP); 5] and bromo(2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N′, N″) manganese(III) toluene solvate [Mn(2-NCH₂C ₆H₅NCTPP)Br·C₆H₅CH ₃; 3·C₆H₅CH₃] have been established. The coordination sphere around the Ni²⁺ ion in 4 (or Pd²⁺ ion in 5) is distorted square planar (DSP), whereas for Mn ³⁺ in 3·C₆H₅CH₃, it is a square-based pyramid with the Br atom lying in the axial site. The g value of 11.34, measured from parallel polarization of the X-band EPR spectra at 4 K, is consistent with a high spin mononuclear manganese(III) centre (S = 2) in 3. The magnitude of the axial (D) zero-field splitting (ZFS) for the mononuclear Mn(III) centre in 3 was determined approximately to be 1.4 cm^-1 by paramagnetic susceptibility measurements and conventional EPR spectroscopy.

Full text of DOI:10.1016/j.poly.2011.09.034

Polyhedron 31 (2012) 339–344
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Metal complexes of 2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrin:
M(2-NCH2C6H5NCTPP) (M = Ni2+, Pd2+) and Mn(2-NCH2C6H5NCTPP)Br
(NCTPP = N-confused 5,10,15,20-tetraphenyl porphyrinate)
b
c,
De-Zhi Hsaio a, Jyh-Horung Chen a, , Shin-Shin Wang , Jo-Yu Tung
⇑
⇑
a Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
b Material and Chemical Research Laboratories, ITRI, Hsin-Chu 300, Taiwan
c Department of Occupational Safety and Health, Chung Hwai University of Medical Technology, Tainan 717, Taiwan
a r t i c l e i n f o
a b s t r a c t
The crystal structures of (2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N0,N00) nickel(II)
methylene chloride solvate [Ni(2-NCH2C6H5NCTPP); 4], (2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-car-
baporphyrinato-N,N0,N00) palladium(II) [Pd(2-NCH2C6H5NCTPP); 5] and bromo(2-aza-2-benzyl-5,10,15,
20-tetraphenyl-21-carbaporphyrinato-N,N0,N00) manganese(III) toluene solvate [Mn(2-NCH2C6H5NCTPP)
BrꢀC6H5CH3; 3ꢀC6H5CH3] have been established. The coordination sphere around the Ni2+ ion in 4 (or Pd2+
ion in 5) is distorted square planar (DSP), whereas for Mn3+ in 3ꢀC6H5CH3, it is a square-based pyramid with
the Br atom lying in the axial site. The g value of 11.34, measured from parallel polarization of the X-band
EPR spectra at 4 K, is consistent with a high spin mononuclear manganese(III) centre (S = 2) in 3. The mag-
nitude of the axial (D) zero-field splitting (ZFS) for the mononuclear Mn(III) centre in 3 was determined
approximately to be 1.4 cmꢁ1 by paramagnetic susceptibility measurements and conventional EPR
spectroscopy.
Article history:
Received 4 August 2011
Accepted 21 September 2011
Available online 7 October 2011
Keywords:
X-ray diffraction
Manganese(III) N-confused porphyrin
Palladium(II) N-confused porphyrin
SQUID
Ó 2011 Elsevier Ltd. All rights reserved.
1. Introduction
l(II) [Ni(2-NCH2C6H5NCTPP); 4], the palladium complex (2-aza-2-
benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N0,N00) pal-
An N-confused porphyrin NCP is a porphyrin isomer with an in-
verted pyrrole ring. There are three main reaction sites in the con-
fused pyrrole ring, i.e. 2-N, 21-C and 3-C [1]. At the external
nitrogen of NCP(2-N), an electrophilic reaction can take place
yielding alkylated products [1,2]. Ziegler and co-workers reported
the synthesis of the 2-N-allyl-5,10,15,20-tetraphenyl N-confused
porphyrin 2-NC3H5NCTPPH (1) [3]. Here in this study, the allyl
group of 1 is modified to a bulky benzyl (Bz) group to derive the
free base 2-N-benzyl-5,10,15,20-tetraphenyl N-confused porphy-
rin, 2-NCH2C6H5NCTPPH (2). Unlike the NH tautomerism that ex-
ists in NCTPPH2 [4], the free base 2 has only one stable form. The
N-confused porphyrin 2 can provide N3 or N3C coordinated sites.
The shortfall in the study on metal complexes of ligand 2
prompted us to undertake the synthesis and structural investiga-
tions of its nickel(II), palladium(II) and manganese(III) complexes.
In this paper, we describe the X-ray structural investigation of
the metallation of 2, leading to the nickel complex (2-aza-2-ben-
zyl-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N0,N00) nicke-
ladium(II) [Pd(2-NCH2C6H5NCTPP); 5] and the manganese(III)
complex bromo(2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carba-
porphyrinato-N,N0,N00) manganese(III) toluene solvate [Mn(2-
NCH2C6H5NCTPP)BrꢀC6H5CH3; 3ꢀC6H5CH3] (Scheme 1). The bulky
benzyl group in this system enhances the crystallization of com-
plexes 4, 5 and 6. The new diamagnetic compound 4 is used as a
diamagnetic correction for the paramagnetic complex 3 in the so-
lid-state magnetic susceptibility measurements [5]. In this paper,
we also focus on the details of the electronic structure of the man-
ganese(III) centre of 3. Studies of the temperature dependence of
the magnetic susceptibility and of the effective moment show that
S = 2 is the ground state for the high-spin mononuclear Mn3+ cen-
tre in 3 at 20 °C. Application of the Bleaney–Bowers equation per-
mits evaluation of D and an average g value for powder samples of
3 [6].
2. Experimental
2.1. Preparation of 3
⇑
Corresponding authors. Tel.: +88 64 228 40411x612; fax: +88 64 228 62547
The preparation of the free base 2-NCH2C6H5NCTPPH (2) is
(J.-H. Chen), tel.: +88 66 267 4567x815; fax: +88 66 289 4028 (J.-Y. Tung).
E-mail addresses: JyhHChen@dragon.nchu.edu.tw (J.-H. Chen), joyuting@mail.
hwai.edu.tw (J.-Y. Tung).
shown in the Supplementary material [7].
A mixture of 2
(0.050 g, 0.071 mmol) and MnBr2 (0.06 g, 0.28 mmol) were
0277-5387/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.poly.2011.09.034

340
D.-Z. Hsaio et al. / Polyhedron 31 (2012) 339–344
3J(H–H) = 7.5 Hz]; 6.65 [d, 2H, o-H(47, 51) of benzyl group, 3J(H–
H) = 7.2 Hz]; 5.11 [s, 2H, H(45) of benzyl group] (Fig. 3). Anal. Calc.
for C51H34N4Niꢀ0.2CH2Cl2ꢀ2.0C4H8O2: C, 74.47; H, 5.32; N, 5.87.
Found: C, 74.24; H, 5.05; N, 5.88%. UV–Vis spectrum, k (nm)
N
Ph
Ph
Ph
Ph
Br
[e
ꢂ 10ꢁ3 (Mꢁ1 cmꢁ1)] in CH2Cl2: 428 (73), 462 (40), 508 (60),
MnBr2
N
N
Mn
560 (8.4), 718 (3.8).
CH3CN
reflux 12h
N
2.3. Preparation of 5
3
60.5 %
Compound 5 was prepared in 62.4% yield in the same way as
described for 4, but using PdCl2 and 2. Compound 5 was dissolved
in CH2Cl2 and layered with EtOAc (ethyl acetate) to get purple crys-
tals for single-crystal X-ray analysis. 1H NMR (599.94 MHz, CDCl3,
R
R
2
3
20 °C) d: 8.31 [s, 1H, H (19)]; 8.02[d, 1H, Hb, 3J(H–H) = 4.8 Hz]; 7.88
N
N
a
Ph
Ph
Ph
4
1
[m, 6H, o-H]; 7.85 [d, 1H, Hb, 3J(H–H) = 5.4 Hz]; 7.83 [d, 1H, Hb,
3J(H–H) = 4.8 Hz]; 7.78 [d, 1H, Hb, 3J(H–H) = 4.8 Hz]; 7.72 [d, 1H,
Hb, 3J(H–H) = 4.8 Hz]; 7.58 [d, 1H, Hb, 3J(H–H) = 4.2 Hz]; 7.56 [m,
10H, m-, p-H]; 7.51 [d, 2H, o-H(34, 38), 3J(H–H) = 7.2 Hz]; 7.34 [t,
1H, m-H(35, 37), 3J(H–H) = 7.8 Hz]; 7.12 [t, 1H, p-H(49) of benzyl
group, 3J(H–H) = 6.9 Hz]; 7.06 [t, 2H, m-H(48, 50) of benzyl group,
3J(H–H) = 7.5 Hz]; 6.66 [d, 2H, o-H(47, 51) of benzyl group, 3J
(H–H) = 7.8 Hz]; 5.14 [s, 2H, H(45) of benzyl group] (Fig. S1 in Sup-
20
19
5
21
6
Ni(OAc)2
24
N
N
7
8
H
Ni
N
18
17
22
N
N
CH3CN
reflux 12h
H
N
16
15
9
23
Ph
10
14
11
4
12
13
68 %
2
R = CH2C6H5
plementary material). Anal. Calc. for
C
51H34N4Pdꢀ0.6H2Oꢀ1.6-
C4H8O2ꢀ0.6CH2Cl2: C, 68.84; H, 4.90; N, 5.54. Found: C, 68.79; H,
R
5.09; N, 5.13%. UV–Vis spectrum, k (nm) [
e
ꢂ 10ꢁ3 (Mꢁ1 cmꢁ1)] in
N
Ph
Ph
Ph
Ph
CH2Cl2: 430 (61), 450 (88), 532 (8.1), 576 (6.5), 638 (3.2), 696
(7.6), 764 (8.9).
PdCl2
N
N
Pd
N
CH2Cl2 / CH3CN
reflux 12h
2.4. Magnetic susceptibility measurements
The solid-state magnetic susceptibility was measured under he-
lium on a Quantum Design MPMS5 SQUID susceptometer from 2 to
300 K at a field of 5 kG. The sample was held in a Kel-F bucket. The
bucket had been calibrated independently at the same field and
temperature. The raw data for 3 was corrected for the molecular
diamagnetism. The diamagnetic contribution of the sample was
measured from the analogous diamagnetic metal complex, 4. De-
tails of the diamagnetic corrections that were made can be found
in Ref. [5].
5
62.4 %
Scheme 1.
refluxed in CH3CN (3 ml) for 12 h. After concentrating the reaction
mixture, the residue was dissolved in CH2Cl2 (30 ml) and filtered.
The filtrate was concentrated and the residue was purified over a
silica gel column (230–400 mesh, 50 g) using CH2Cl2/EtOAc [9:1
(v/v)] as the eluent to yield a red solution of 3. Removal of the sol-
vent gave 3 as a green solid (0.038 g, 0.043 mmol, 60.5%). Com-
pound 3 was dissolved in toluene and layered with hexane to
afford green crystals for single crystal X-ray analysis. Anal. Calc.
for C51H34BrMnN4ꢀ2.5H2O: C, 69.39; H, 4.45; N, 6.35. Found: C,
2.5. Spectroscopy
ESR spectra were measured on an X-band Bruker EMX-10 spec-
trometer equipped with an Oxford Instruments liquid helium cryo-
stat. Magnetic field values were measured with a digital counter.
The X-band resonator was a dual-mode cavity (Bruker ER 4116
DM). Proton NMR spectra were recorded at 599.95 MHz on a Var-
ian Unity Inova-600 spectrometer locked on deuterated solvent
and referenced to the solvent peak. Proton NMR is relative to CDCl3
at d = 7.24. The mass spectra [MS(ESI)] were recorded on a Finnigan
TSQ Ultra EMR mass spectrometer with an ESI source. UV–Vis
69.42; H, 4.19; N, 6.55%. UV–Vis spectrum, k (nm) [
e
ꢂ 10ꢁ3
(Mꢁ1 cmꢁ1)] in CH2Cl2: 394 (32), 458 (19), 508 (60), 582 (5.0),
640 (2.5), 748 (5.0).
2.2. Preparation of 4
A mixture of 2 (0.050 g, 0.071 mmol) and Ni(OAc)2 (0.15 g,
0.60 mmol) were refluxed in CH3CN (5 ml) for 12 h. After concen-
trating the reaction mixture, the residue was dissolved in 10 ml
of CH2Cl2 and filtered. The filtrate was concentrated and the resi-
due was recrystallized from CH2Cl2–hexane [1:1 (v/v)] to afford 4
(0.037 g, 0.048 mmol, 68%) as a purple solid. Compound 4 was
redissolved in CH2Cl2 and layered with MeOH to afford purple crys-
tals for single-crystal X-ray analysis. 1H NMR (599.94 MHz, CDCl3,
spectra were recorded at 20 °C on
spectrophotometer.
a
Hitachi U-3210
2.6. Crystallography
Table 1 presents the crystal data as well as other information for
3, 4 and 5. Measurements were taken on a Bruker AXS SMART-
1000 diffractometer using monochromatized Mo K
(k = 0.71073 Å). Semi-empirical absorption corrections were made
for the three complexes. The structures were solved by direct
methods (SHELXTL-97) [8] and refined by the full-matrix least-
squares method. All non-hydrogen atoms were refined with aniso-
tropic thermal parameters, whereas all hydrogen atoms were
placed in calculated positions and refined with a riding model.
We have used SQUEEZE to remove the disordered solvent CH2Cl2
a radiation
20 °C) d: 8.38 [s, 1H, H (3)]; 8.05 [d, 1H, Hb, 3J(H–H) = 4.8 Hz]; 7.93
a
[d, 1H, Hb, 3J(H–H) = 4.8 Hz]; 7.91 [d, 1H, Hb, 3J(H–H) = 4.8 Hz]; 7.84
[m, 6H, o-H]; 7.82 [d, 1H, Hb, 3J(H–H) = 5.4 Hz]; 7.70 [d, 1H, Hb(17),
3J(H–H) = 5.4 Hz]; 7.67 [d, 1H, Hb(18), 3J(H–H) = 4.8 Hz]; 7.56 [m,
10H, m-, p-H]; 7.46 [d, 2H, o-H(40, 44), 3J(H–H) = 6.6 Hz]; 7.33 [t,
1H, m-H(41, 43), 3J(H–H) = 7.8 Hz]; 7.13 [t, 1H, p-H(49) of benzyl
group, 3J(H–H) = 7.5 Hz]; 7.07 [t, 2H, m-H(48, 50) of benzyl group,

D.-Z. Hsaio et al. / Polyhedron 31 (2012) 339–344
341
Table 1
3. Results and discussion
3.1. Structures of 3ꢀC6H5CH3, 4 and 5
Crystal data for 3ꢀC6H5CH3, 4 and 5.
Compound
3ꢀC6H5CH3
58H42N4BrMnN4
4
5
Empirical
formula
Formula
weight
Space group
Crystal
system
a (Å)
C
C51H34N4Ni
C51H34N4Pd
The complexes Ni(2-NCH2C6H5NCTPP) (4) and Pd(2-
NCH2C6H5NCTPP) (5) were synthesized in 68% and 62.4% yields,
respectively, by reacting 2 with excess Ni(OAc)2 or PdCl2 in CH3CN
or CH2Cl2/CH3CN under aerobic conditions (Scheme 1).
The complex Mn(2-NCH2C6H5NCTPP)Br (3) was produced in
60.5% yield by heating a solution of 2 in CH3CN under aerobic con-
ditions with an excess of MnBr2 (Scheme 1).
The X-ray frameworks for 3ꢀC6H5CH3, 4 and 5 are depicted in
Fig. 1. All these structures, distorted square planar (DSP) for the
nickel centre of 4 (or palladium centre of 5) and five-coordinate
manganese centre of 3ꢀC6H5CH3, bond with three nitrogen atoms
(N3) of the porphyrin and one carbon atom (C) of the inverted pyr-
role ring in common, whilst compound 3ꢀC6H5CH3 has an addition
Br ligand in the axial site.
929.81
761.53
809.22
ꢀ
ꢀ
P21/n
monoclinic
P1
triclinic
P1
triclinic
10.3156(3)
15.9025(5)
26.929 (1)
90
97.827(4)
90
4376.4(3)
4
1912
11.8610(4)
13.3696(3)
13.7129(4)
102.924(2)
109.836(3)
91.199(2)
1982.6(1)
2
11.8973(5)
13.4226(5)
13.5182(6)
102.531(3)
108.893(4)
92.037(3)
1980.7(1)
2
b (Å)
c (Å)
a
(°)
b (°)
c
(°)
V (Å3)
Z
F(000)
792
1.276
0.530
828
1.357
0.510
Dcalc (g cmꢁ3
)
1.411
1.261
k(Mo K
a
)
(mmꢁ1
)
The distortion in the five-coordinate complex 3ꢀC6H5CH3 can be
S
1.057
1.081
1.066
quantified by the ‘‘degree of trigonality’’ which is defined as
Crystal size
(mm)
h (°)
T (K)
Number of
0.34 ꢂ 0.32 ꢂ 0.26 0.60 ꢂ 0.22 ꢂ 0.08 0.46 ꢂ 0.32 ꢂ 0.24
s
= (b ꢁ
the Lbasal–M–Lbasal angles [9]. The limiting values are
ideal tetragonal geometry and = 1 for an ideal trigonal bipyramid
geometry. In the present case, we find b = 161.6(2)° [N(1)–Mn–
N(3)] and = 159.8(2) [C(17)–Mn–N(2)]. Thus the value calcu-
a
)/60, where b is the largest and
a
the second largest of
s
= 0 for an
2.82–29.12
110(2)
10038
2.54–29.25
120(2)
9052
2.84–29.23
110(2)
9137
s
reflections
measured
a
s
lated for 3ꢀC6H5CH3 is 0.03. Hence the geometry around Mn(III)
in 3ꢀC6H5CH3 is best described as a square-based pyramid in which
the apical site is occupied by the Br atom. The Mn–C(17), Mn–N(1),
Mn–N(2), Mn–N(3) and Mn–Br bond lengths in 3ꢀC6H5CH3 are
2.007(5), 2.036(4), 2.047(4), 2.035(4) and 2.487(1) Å, respectively.
The crystal packing of complex 3 is shown in Fig. 2. The short inter
atomic contacts of H(45B). . .BrA, 2.964(4) Å, for 3 is much longer
than that of H(39B). . .BrBA, 2.800(5) Å [or H(45B). . .BrC,
2.846(4) Å] in Mn(2-NC3H5NCTPP)Br [or Mn(2-NCH2-p-C6H4-
CO2CH3NCTPP)Br] [10].1 Hence there are no intermolecular hydro-
gen bonds linking the individual monomer of 3 into a dimer in the
solid state. Complex 3 is monomeric in the solid phase.
In 4 (or 5), the geometry about Ni (or Pd) is distorted square-
planar and the bond distances are as follows: Ni–C(2) = 1.907(2),
Ni–N(1) = 1.957(2), Ni–N(2) = 1.968(2) and Ni–N(3) = 1.940(2) Å
for 4; Pd–C(17) = 1.973(3), Pd–N(1) = 2.027(2), Pd–N(2) = 2.053(2)
and Pd–N(3) = 2.014(2) Å for 5. The average Ni–N distance of
1.955(2) in 4 is comparable to the Ni–N distances in the planar
Number of
5184
6338
6951
reflections
observed
a
R1
wR2
0.0769
0.2209
0.0462
0.1175
0.0413
0.1111
b
P
P
a
R1 = [ ||Fo| ꢁ |Fc||/ |Fo|].
P
P
wR2 = [ w(F0 ꢁ Fc2)2/ w(F02)2]1/2
.
b
2
Table 2
Selected bond distances (Å) and angles (°) for compounds 3ꢀC6H5CH3, 4 and 5.
3ꢀC6H5CH3
Bond lengths (Å)
Mn–N(1)
Mn–N(2)
Mn–N(3)
2.036(4)
2.047(4)
2.035(4)
Mn–C(17)
Mn–Br
2.007(5)
2.487(1)
Bond angles (°)
Br–Mn–N(1)
Br–Mn–N(2)
Br–Mn–N(3)
Br–Mn–C(17)
N(2)–Mn–N(3)
104.8(1)
97.3 (1)
93.6 (1)
102.9(1)
90.4 (2)
C(17)–Mn–N(1)
C(17)–Mn–N(2)
C(17)–Mn–N(3)
N(1)–Mn–N(2)
N(1)–Mn–N(3)
87.6 (2)
159.8(2)
87.3(2)
88.3(2)
161.6(2)
Ni(CTTP)
derivative
[1.955(3) Å,
CTTP = 2-aza-21-carba-
5,10,15,20-tetra-p-tolylporphyrinate] but the Ni–C distance of
1.907(2) Å in 4 is smaller than the Ni–C distance in the same
Ni(CTTP) complex [1.963(3) Å] [11]. The average Pd–N and Pd–C
distances are 2.031(2) and 1.973(3) Å in 5, and these are both smal-
ler than those of Pd(II)–N (2.09 Å) and Pd(II)–C (2.00 Å) in the
square-planar Pd(NCTPP) [12].
4
Bond lengths (Å)
Ni–N(1)
Ni–N(2)
1.957(2)
1.968(2)
Ni–N(3)
Ni–C(2)
1.940 (2)
1.907(2)
Bond angles (°)
N(1)–Ni–N(2)
N(1)–Ni–N(3)
N(2)–Ni–N(3)
3.2. 1H NMR spectroscopic data for 4 and 5 in CDCl3
90.37(8)
178.47(9)
90.62(8)
N(1)–Ni–C(2)
N(2)–Ni–C(2)
N(3)–Ni–C(2)
89.38(9)
178.3(1)
89.67(9)
In solution, the 1H NMR spectrum exhibits six pyrrole reso-
nances [Hb(18), Hb(17), Hb(13), Hb(12), Hb(8), Hb(7)] for 4 (Fig. 3).
The doublet at 7.70 ppm is assigned as Hb(17) with 3J(H–
H) = 5.4 Hz and the other doublet at 7.67 ppm is due to Hb(18) with
3J(H–H) = 4.8 Hz. The doublet at 8.05 ppm is assigned as Hb with
3J(H–H) = 5.1 Hz and the other doublet at 7.82 ppm is due to Hb
with 3J(H–H) = 5.1 Hz. The doublet at 7.93 ppm is assigned as Hb
with 3J(H–H) = 4.8 Hz and the other doublet at 7.90 ppm is due
5
Bond lengths (Å)
Pd–N(1)
Pd–N(2)
2.027(2)
2.053(2)
Pd–N(3)
Pd–C(17)
2.014(2)
1.973(3)
Bond angles (°)
N(1)–Pd–N(2)
N(1)–Pd–N(3)
N(2)–Pd–N(3)
90.10(9)
178.4 (1)
90.7(1)
N(1)–Pd–C(17)
N(2)–Pd–C(17)
N(3)–Pd–C(17)
89.64(1)
178.4(1)
89.6(1)
1
Mn(2-NCH2CH = CH2NCTPP)Br = bromo(2-aza-2-allyl-5,10,15,20-tetraphenyl-21-
carbaporphyrinato-N,N0,N00) manganese (III); Mn(2-NCH2-p-C6H4-CO2CH3NCTPP) Br
= [2-aza-2-(40-methyl methylbenzoate)-5,10,15,20-tetraphenyl-21-carbaporphyrina-
to-N,N0,N00] manganese(III).
for the Ni structure (4). Table 2 lists selected bond distances and
angles for the three complexes.

342
D.-Z. Hsaio et al. / Polyhedron 31 (2012) 339–344
Fig. 1. Molecular structures of (a) [Mn(2-NCH2C6H5NCTPP)BrꢀC6H5CH3; 3ꢀC6H5CH3]; (b) [Ni(2-NCH2C6H5NCTPP); 4] and (c) [Pd(2-NCH2C6H5NCTPP); 5], with 30% thermal
ellipsoids. Hydrogen atoms are omitted for clarity.
to Hb with 3J(H–H) = 4.8 Hz. The external benzyl ligand (Bz) unit in
4 gave rise to series of 1H resonances at 7.13 [t, 1H, p-H(49), 3J(H–
H) = 7.5 Hz], 7.07 [t, m-H(48, 50), 3J(H–H) = 7.5Hz], 6.65 [d, o-H(47,
51), 3J(H–H) = 7.2 Hz] and 5.11 [s, H(45)].
In solution, the 1H NMR spectrum exhibits six pyrrole reso-
nances [Hb(13), Hb(12), Hb(7), Hb(8), Hb(3), Hb(2)] for 5 (Fig. S1 in
Supplementary material). The doublet at 8.02 ppm is assigned as
Hb with 3J(H–H) = 5.1 Hz and the other doublet at 7.85 ppm is
due to Hb with 3J(H–H) = 5.1 Hz. The doublet at 7.83 ppm is as-
signed as Hb with 3J(H–H) = 4.8 Hz and the other doublet at
7.78 ppm is due to Hb with 3J(H–H) = 4.8 Hz. The doublet at
7.72 ppm is assigned as Hb with 3J(H–H) = 4.5 Hz and the other
doublet at 7.58 ppm is due to Hb with 3J(H–H) = 4.5 Hz. The exter-
nal benzyl ligand (Bz) unit in 5 gave rise to series of 1H resonances
at 7.12 [t, 1H, p-H(49), 3J(H–H) = 7.5 Hz], 7.06 [t, m-H(48, 50), 3J(H–
H) = 7.5 Hz], 6.66 [d, o-H(47, 51), 3J (H–H) = 7.8 Hz] and 5.14 [s,
H(45)]. The diamagnetic properties of 4 and 5 were inferred from
their diamagnetic 1H NMR spectra in CDCl3.
Fig. 2. The crystal packing in the unit cell for complex 3.
Fig. 3. 1H NMR spectrum for 4 at 599.95 MHz in CDCl3 at 20 °C showing six different b-pyrrole protons Hb, phenyl protons (o-H, m, p-H) and protons of the benzyl ligand (Bz).
Chemical shifts are in ppm from CDCl3 at 7.24 ppm.

D.-Z. Hsaio et al. / Polyhedron 31 (2012) 339–344
343
Fig. 4. Temperature variation of the molar magnetic susceptibility (vm) and effective magnetic moment (leff) for a powder sample of 3 in the range 2–300 K. Points represent
the experimental data; solid lines represent the least-squares fit of the data to Eq. (1).
3.3. ESR studies
their standard meanings. The best fits, as represented in Fig. 4, gave
the values g = 1.84, jDj = 1.4 cmꢁ1, p = 0.9999 and TIP = ꢁ1.1 ꢂ 10ꢁ4
(cm3/mol). This jDj value lies in the 1 < jDj < 4.9 cmꢁ1 range found
in related Mn(III) porphyrin complexes.
The X-band (9.377 GHz) ESR spectrum using parallel polariza-
tion recorded for 3 as a powder solid at 20 °C is shown in Fig. S2
(Supplementary material). As has been similarly observed in other
Mn(III) complexes, a single line, centred at g = 11.34, is found [13–
15]. These signals are attributed to a forbidden transition within
the j2þi and j2ꢁi non-Kramer’s doublet for a high-spin mononu-
clear Mn3+ (S = 2) complex [14,15].
4. Conclusion
We have investigated three new inverted N-confused porphyrin
metal complexes, namely paramagnetic 3 and two diamagnetic
complexes 4 and 5, and their X-ray structures were established.
The conventional ESR spectroscopy and the magnetic susceptibility
measurements were reported to evaluate the ZFS parameter D for
the high-spin mononuclear Mn(III) (S = 2) complex 3.
3.4. Magnetic properties
Magnetic data for complex 3 are reported in Fig. 4 in the forms
of vM and leff versus T. As can be seen in Fig. 4, the value of leff var-
ies from 4.53lB at 300 K to 4.18lB at 2 K. The magnetic moment
clearly shows a plateau equal to 4.50lB at high temperatures
(300–15 K), below which it decreases again. The abrupt rise in
leff in the range 2 < T < 15 K is characteristic of a compound with
significant zero-field splitting (ZFS). The room-temperature effec-
tive moment of 4.53lB is lower than the spin-only moment of
4.9lB for an S = 2 system, but consistent with that of other high-
spin Mn(III) complexes in which g < 2. The vM versus T (or leff ver-
sus T) data could fit into the expression (Eq. (1)) derived from the
Acknowledgements
Financial support from the National Science Council of the
R.O.C. under Grants NSC 99-2113-M-005-006 and 99-2119-M-
273-001 is gratefully acknowledged. We thank Dr. S. Elango for
helpful discussions.
Appendix A. Supplementary data
2
2
2
Hamiltonian H ¼ D½Sz ꢁ 1 SðS þ 1Þꢃ þ EðSx ꢁ Sy Þ þ g
l
BHS, where H is
^
the applied magnetic fie3ld, g is the g tensor, S = 2 is the electronic
spin, and D and E are the parameters which describe the effects
of axial and rhombic ligand fields, respectively [16]. As a first
approximation, we set E = 0 in 3. The data were inserted into the
Bleaney–Bowers equation (Eq. (1)) [6]
The preparation of 2 is shown in the Supplementary material.
CCDC 834007, 834008 and 834009 contains the supplementary
crystallographic data for 3, 4 and 5, respectively. These data can
be obtained free of charge via http://www.ccdc.cam.ac.uk/conts/
retrieving.html, or from the Cambridge Crystallographic Data
Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: (+44) 1223-
336-033; or e-mail: deposit@ccdc.cam.ac.uk. Supplementary data
associated with this article can be found, in the online version, at
doi:10.1016/j.poly.2011.09.034.
8
Mn3þ
>
>
>
>
<
zfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflffl}|fflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflfflffl{
"
#
1
8
8 þ 2e3y þ y ðꢁ 3
ꢁ
28 e3y þ 12e4y
Þ
0:3749
1
3
3
¼
g2 p ꢀ
ꢀ
vM
T
2 þ 2e3y þ e4y
>
>
>
>
:
References
9
>
=
[1] X. Li, B. Liu, P. Yi, R. Yi, X. Yu, P.J. Chimelewski, J. Org. Chem. 76 (2011) 2345.
[2] T. Ishizuka, H. Yamasaki, A. Osuka, H. Furuta, Tetrahedron Lett. 63 (2007) 5137.
[3] W. Qu, T. Ding, A. Cetin, J.D. Harvey, M.J. Taschner, C.J. Ziegler, J. Org. Chem. 71
(2006) 811.
[4] P.J. Chimelewski, L. Latos-Grazynski, J. Chem. Soc., Perkin Trans. 2 (1995) 503.
[5] R.S. Drago, Physical Methods for Chemists, second ed., Sanders College
Publishing, New York, 1992. p. 473, 591.
þ ð1 ꢁ pÞ ꢂ 2:917 þ TIP
ð1Þ
|fflfflfflfflfflfflfflfflfflfflfflffl{zfflfflfflfflfflfflfflfflfflfflfflffl}>
;
Mn2þðimpurityÞ
pffiffiffiffiffiffiffiffiffi
ꢁ1
where y ¼ 1:44 Dðcm and
leff = 2.828
vMT.
Þ
T
Here g is the average g value, TIP is the temperature independent
[6] B. Bleaney, K.D. Bowers, Proc. R. Soc. Lond. A214 (1952) 451.
[7] D.Z. Hsaio, J.H. Chen, S.S. Wang, J.Y Tung, Polyhedron 30 (2011) 2908.
paramagnetism, p is the fraction of Mn3+, and other symbols have

344
D.-Z. Hsaio et al. / Polyhedron 31 (2012) 339–344
[8] G.M. Sheldrick, SHELXL-97, Program for the Refinement of Crystal structure from
[12] H. Furuta, N. Kubo, H. Maeda, T. Ishizuka, A. Osuka, H. Nanami, T. Ogawa, Inorg.
Chem. 39 (2000) 5424.
[13] E.P. Talsi, K.P. Bryliakov, Mendeleev Commun. (2004) 111.
[14] S.L. Dexheimer, J.W. Gohdes, M.K. Chan, K.S. Hagen, W.H. Armstrong, M.P.
Klein, J. Am. Chem. Soc. 111 (1989) 8923.
[15] K.P. Bryliakov, D.E. Babushkon, E.P. Talsi, Mendeleev Commun. (1999) 29.
[16] S.W. Hung, F.A. Yang, J.H. Chen, S.S. Wang, J.Y. Tung, Inorg. Chem. 47 (2008)
7202.
Diffraction Data, University of Gottingen, Gottingen, Germany, 1997.
[9] A.W. Addison, T.N. Rao, J. Reedijk, J.V. Rijn, G.C. Verschoor, J. Chem. Soc., Dalton
Trans. (1984) 1349.
[10] C. Yang, M.Y. Tsai, S.W. Hung, J.H. Chen, S.S. Wang, J.Y. Tung, personal
communication.
[11] P.J. Chmielewski, L. Lato-Grazynski, K. Rachlewicz, T. Glowiak, Angew. Chem.,
Int. Ed. 33 (1994) 779.