Preparation and characterization of macrocyclic dinickel complexes coligated by tetrazolate ligands

Article abstract of DOI:10.1515/znb-2008-0503

The dinuclear nickel(II) complex [Ni₂LCl]⁺ (1), where (L)^2- represents a 24-membered macrocyclic hexamine-dithiophenolate ligand, reacts readily with 5-R-tetrazolate ligands to give the complexes [Ni₂L(RCN₄)]⁺, where R = H (2), Me (3), Ph (4). The new complexes were either isolated as perchlorate or tetraphenylborate salts and fully characterized by elemental analysis, UV/Vis, and IR spectroscopy. The structures of 2[BPh₄] · MeCN, 3[BPh ₄] · 2MeCN, and 4[BPh₄] · MeCN were determined by X-ray crystallography, showing that all tetrazolate units are in a 2,3-bridging mode to generate dioctahedral N₃Ni(μ-S) ₂(μ-N₄CR)NiN₃ core structures. The RCN ₄^- groups interact less strongly with the [Ni ₂L]²⁺ fragment than pyrazolate ligands (CH) ₃N₂^- as reflected in the longer Ni-N distances.

Full text of DOI:10.1515/znb-2008-0503

Preparation and Characterization of Macrocyclic Dinickel Complexes
Coligated by Tetrazolate Ligands
Vasile Lozana, Sergei V. Voitekhovichb, Pavel N. Gaponikb, Oleg A. Ivashkevichb,
and Berthold Kerstinga
a Institut fu¨r Anorganische Chemie, Universita¨t Leipzig, Johannisallee 29, D-04103 Leipzig,
Germany
b Research Institute for Physical Chemical Problems, Belarusian State University,
Leningradskaya 14, 220030 Minsk, Belarus
Reprint requests to Prof. Dr. Berthold Kersting. Fax: +49 341 973 6199.
E-mail: b.kersting@uni-leipzig.de
Z. Naturforsch. 2008, 63b, 496 – 502; received January 31, 2008
The dinuclear nickel(II) complex [Ni2LCl]+ (1), where (L)2− represents a 24-membered macro-
cyclic hexamine-dithiophenolate ligand, reacts readily with 5-R-tetrazolate ligands to give the com-
plexes [Ni2L(RCN4)]+, where R = H (2), Me (3), Ph (4). The new complexes were either isolated
as perchlorate or tetraphenylborate salts and fully characterized by elemental analysis, UV/Vis, and
IR spectroscopy. The structures of 2[BPh4] · MeCN, 3[BPh4] · 2MeCN, and 4[BPh4] · MeCN were
determined by X-ray crystallography, showing that all tetrazolate units are in a−2,3-bridging mode to
generate dioctahedral N3Ni(µ-S)2(µ-N4CR)NiN3 core structures. The RCN4 groups interact less
−
strongly with the [Ni2L]2+ fragment than pyrazolate ligands (CH)3N2 as reflected in the longer
Ni–N distances.
Key words: Macrocyclic Ligands, Nickel Complexes, Coordination Chemistry,
Tetrazolate Complexes
Introduction
Several examples of dinuclear [Ni2L(Lꢀ)]n+ com-
plexes supported by the macrocyclic hexaaza-dithio-
phenolate ligand L2− have now been characterized
(Scheme 1). These include complexes with Lꢀ = Cl−
[1], OH− [2], NO2−, NO3−, N3−, N2H4 [3], BH4− [4],
various carboxylates [5 – 9], SH−, S62−, SPh− [3, 10],
and some biolo−gically relevant molecules such as
2−
HCO3−, H2PO4 [11], and SO4 [12]. In previ-
ous work, we have also described the synthesis of a
few [Ni2L(Lꢀ)]n+ complexes bearing small five- and
six-membered N-heterocycles as coligands. The X-ray
crystal structures of the pyrazolate ((CH)3N2−, pz) and
pyridazine ((CH)4N2, pydz) complexes [Ni2L(pz)]+
and [Ni2L(pydz)]2+ have been reported [3]. In view of
the biological and medicinal importance of azoles [13],
we considered it worthwhile to prepare further com-
plexes of this type to gain more insight into the binding
of these compounds towards the [Ni2L]2+ fragment.
Here we describe the synthesis and characterization of
Scheme 1. Structure of dinuclear complexes [Ni2L(Lꢀ)]n+
supported by the hexaaza-dithiophenolate ligand (L2−) (Lꢀ =
coligand, n = 1 – 2).
three novel dinickel complexes bearing tetrazolate lig-
ands and explore their structural features. A survey of
the literature reveals that little is known of such coor-
dination compounds [14].
c
0932–0776 / 08 / 0500–0496 $ 06.00 ꢀ 2008 Verlag der Zeitschrift fu¨r Naturforschung, Tu¨bingen · http://znaturforsch.com
Unauthenticated
Download Date | 11/15/15 9:16 AM

V. Lozan et al. · Macrocyclic Dinickel Complexes
497
Results and Discussion
Synthesis and characterization of compounds
Tetrazole was prepared by a modified method based
on the heterocyclization of triethylorthoformate with
sodium azide and ammonium chloride [15]. The prepa-
ration of the 5-R-tetrazoles (R = Me, Ph) from the cor-
responding nitriles and sodium azide has been reported
previously [16], as has the synthesis of the complex
[Ni2LCl]ClO4 (1) [1], which was used as a starting
material in this complexation study. All tetrazolates
(prepared in situ from the free tetrazoles and triethy-
lamine) were found to react smoothly with complex 1
in methanol over reaction times of several hours to give
the green tetrazolate complexes 2 – 4, which could be
isolated as highly crystalline perchlorate salts in yields
> 80 % (Scheme 2). The behavior of the tetrazolate
ligands is thus much like that of carboxylate ligands,
which also readily displace the bridging halide ion
in 1 [5]. Complexes 2[ClO4] – 4[ClO4] are quite sta-
ble in solution and could therefore be subjected to salt
metathesis with NaBPh4 to generate the corresponding
tetraphenylborate salts.
Scheme 2. Synthesis of tetrazolate complexes 2 – 4.
The new compounds are air-stable both in the solid
as well as in solution, readily soluble in a variety
of polar aprotic organic solvents such as dimethyl-
formamide, acetonitrile, and dichloromethane, but less
soluble in alcohols and virtually insoluble in water.
Upon heating, they decompose without melting or ex-
ploding.
All compounds gave satisfactory elemental analy-
ses and were characterized by IR and UV/Vis spec-
troscopy, and by X-ray structure analysis. In acetoni-
trile solution all complexes feature four intense UV/Vis
absorption maxima in the range 250– 500 nm, charac-
teristic for nickel complexes of (L2−) [10]. The ones
at ∼ 270 nm and ∼ 300 nm can be attributed to π −π∗
transitions within the aromatic rings of the support-
ing ligand, whereas those at ∼ 330 nm and ∼ 381 nm
can be assigned to thiophenolate → NiII charge trans-
fer absorptions. UV/Vis absorptions due to the tetra-
zolates were not detected. Above 500 nm, each com-
Scheme 3. Coordination modes of tetrazolate ligands in
metal complexes.
transitions. From the ν1 transition one can obtain a
rough estimate of the octahedral splitting parameters
of ∆oct ≈ 8810 cm−1. Such low values for ∆oct (i. e.
∆
oct [Ni(H2O)6]2+ = 8500 cm−1 [17]) are quite typical
for [Ni2L(Lꢀ)]+ complexes containing NiIIN4S2 chro-
mophores (i. e. ∆oct (Lꢀ = pyrazolate) = 8475 cm−1
(Lꢀ = hydrazine) = 8977 cm−1, ∆oct (Lꢀ = pyri-
,
∆
oct
dazine) = 9132 cm−1 [3]).
The tetrazolate ligands have been shown to exhibit
plex exhibits two weak absorption bands at 619
1
and 1135 1 nm. A dependence of the band posi- a rich variety of coordination modes [14]. As shown
tions on the substituent in the 5-position of the tetra- in Scheme 3 the tetrazolate can either coordinate by
zolate ligand is thus not significant. The two bands can means of one, two, three or four endocyclic nitrogen
3
be assigned to the spin-allowed 3A2g → T1g (ν2) and atoms. The actual type of coordination depends on the
3
3A2g → T2g (ν1) transitions of a nickel(II) (S = 1) ion electronic and steric characteristics of the substituent R
3
(in Oh symmetry for simplicity). The 3A2g → T1g (P) and its capability to participate in binding with the
transition is presumably obscured by the strong LMCT metal ion. Additionally, in mixed ligand complexes
Unauthenticated
Download Date | 11/15/15 9:16 AM

498
V. Lozan et al. · Macrocyclic Dinickel Complexes
the coligand also influences the coordination modes
of tetrazolates [14]. Based on previous structures of
hexaaza-dithiophenolate complexes [Ni2L(Lꢀ)]n+ with
N-heterocycles [3] one can assume a coordination of
tetrazolate anions through two neighboring nitrogen
atoms. In general, the 2,3-bridging mode [18] is fa-
vored over the 1,2-bridging mode [19] such that the
former is expected for the present compounds. The
crystal structure determinations described below have
shown that this is indeed the case for all three com-
plexes 2 – 4.
Description of crystal structures
The structures of complexes 2[BPh4] · MeCN,
3[BPh4] · 2MeCN and 4[BPh4] · MeCN were deter-
mined by single-crystal X-ray diffraction. ORTEP
views of the molecular structures of the cations 2 –
4 are presented in Figs. 1 – 3. Selected bond lengths
Fig. 3. Structure of cation 4 in crystals of 4[BPh4] · MeCN
with thermal ellipsoids drawn at 30 % probability. Hydrogen
atoms are omitted for reasons of clarity.
and angles are compiled in Table 1. The atomic num-
bering scheme used for the central N3Ni(µ-S)2(µ-
N4CR)NiN3 core in 2 was also applied for 3 and 4
to facilitate structural comparisons. The data for
[Ni2L(pz)]+ (5) and [Ni2L(pydz)]2+ (6) [3] are also
included in Table 1 for comparison.
All tetrazolates bind to the [Ni2L]2+ fragment as
bidendate bridges through their two ring nitrogen
atoms N(7) and N(9). Consequently, the Ni...Ni dis-
tances are nearly identical in the three compounds (av-
˚
erage 3.394(1) A). The macrocycle assumes a bowl-
shaped conformation, which is typical for [Ni2L(Lꢀ)]+
complexes when coligated by multi-atom bridging lig-
ands Lꢀ [3, 20]. All tetrazolate units are essentially
planar. The N–N and N–C distances of the tetrazo-
late rings in 2 – 4 differ significantly from the cor-
responding distances of the free 5-R-tetrazoles. Par-
ticularly affected are the N(7)–N(9) bonds. Thus,
for 1-H-tetrazole and 5-methyltetrazole these bonds
Fig. 1. Structure of cation 2 in crystals of 2[BPh4] · MeCN
with thermal ellipsoids drawn at 30 % probability. Hydrogen
atoms, except H(39), are omitted for reasons of clarity.
˚
˚
lengths are 1.295(3) A [21] and 1.285(3) A [22], much
˚
shorter than in 2 – 4, averaging at 1.354(3) A. Similar
changes were observed for a related tetrazolate com-
plex with 2,3-µ-coordination [18] albeit to a lesser ex-
tent. The larger differences in 2 – 4 presumably relate
to the stronger Lewis acidity of the nickel(II) ions.
All three N–N bond lengths in 3 are identical within
experimental error, while they vary from 1.317(2)
˚
˚
to 1.367(2) A in 2 and from 1.317(4) to 1.360(4) A
Fig. 2. Structure of cation 3 in crystals of 3[BPh4] · 2MeCN
with thermal ellipsoids drawn at 30 % probability. Hydrogen
atoms, except those bonded to C(40), are omitted for reasons
of clarity.
in 4.
The average Ni–N(heterocycle) bond lengths
are 2.079(2) A (2), 2.067(2) A (3), and 2.061(3) A
˚
˚
˚
Unauthenticated
Download Date | 11/15/15 9:16 AM

V. Lozan et al. · Macrocyclic Dinickel Complexes
499
Table 1. Selected bond lengths
2
3
4a
5
6
˚
(A) in complexes 2 – 6.
Ni(1)–N(7)
Ni(1)–N(1)
Ni(1)–N(2)
Ni(1)–N(3)
Ni(1)–S(1)
Ni(1)–S(2)
Ni(2)–N(9)
Ni(2)–N(4)
Ni(2)–N(5)
Ni(2)–N(6)
Ni(2)–S(1)
Ni(2)–S(2)
Ni–Nb
2.081(2)
2.319(2)
2.168(2)
2.227(2)
2.5152(7)
2.4626(7)
2.077(2)
2.237(2)
2.173(2)
2.311(2)
2.5194(9)
2.4509(6)
2.239(2)
2.079(2)
2.4870(8)
3.455(1)
2.063(2)
2.306(2)
2.162(3)
2.232(3)
2.5044(8)
2.4664(8)
2.071(2)
2.204(2)
2.170(2)
2.324(2)
2.5012(8)
2.4699(8)
2.233(2)
2.067(2)
2.4855(8)
3.425(1)
2.071(3)/2.065(3)
2.346(3)/2.317(3)
2.171(3)/2.159(3)
2.207(3)/2.221(3)
2.525(1)/2.532(1)
2.431(1)/2.443(1)
2.051(3)/2.055(3)
2.205(3)/2.210(3)
2.150(3)/2.154(3)
2.332(3)/2.338(3)
2.530(1)/2.515(1)
2.450(1)/2.441(1)
2.235(3)/2.233(3)
2.061(3)/2.060(3)
2.484(1)/2.483(1)
3.443(1)/3.450(1)
2.044(2)
2.337(2)
2.179(2)
2.272(2)
2.500(1)
2.450(1)
2.038(2)
2.270(2)
2.178(2)
2.342(2)
2.499(1)
2.455(1)
2.263(2)
2.041(2)
2.476(1)
3.389(1)
2.117(2)
2.343(2)
2.132(2)
2.281(2)
2.453(1)
2.450(1)
2.138(2)
2.338(2)
2.126(2)
2.268(2)
2.450(1)
2.451(1)
2.248(2)
2.128(2)
2.451(1)
3.392(1)
Ni–Nhetb,c
Ni–Sb
Ni·Ni
N(7)–N(9)
N(7)–N(8)
N(9)–N(10)
C(39)–N(8)
C(39)–N(10)
a There are two crystallograph-
ically independent molecules
A and B in the asymmetric
unit. The second value refers to
1.367(2)
1.325(2)
1.317(2)
1.331(3)
1.341(3)
1.331(3)
1.330(3)
1.335(3)
1.333(4)
1.333(4)
1.346(4)/1.360(4)
1.333(4)/1.320(4)
1.328(4)/1.317(4)
1.341(5)/1.347(5)
1.347(5)/1.354(5)
–
–
–
–
–
–
–
–
–
–
b
molecule B; average values;
c
Ni–Nhet = N(heterocycle).
(4), intermediate between those in the pyrazolato Experimental Section
˚
and pyridazine complexes 5 (mean 2.043(2) A)
Complex 1[ClO4] ([Ni2LCl][ClO4]) [1], and the ligands
(5-methyl- and 5-phenyltetrazole) [16] were prepared ac-
cording to the literature procedures. All other compounds
were purchased. Melting points were determined with a Wa-
ters VG-ZAB-HSQ instrument in open glass capillaries and
are uncorrected, infrared spectra were recorded on a Bruker
Vector27 FT-IR-spectrometer. Electronic absorption spectra
were taken on a JASCO V670 UV/Vis spectrometer, elemen-
tal analyses on a VARIO EL-elemental analyzer.
˚
and 6 (mean 2.175(2) A). This suggests that the
binding affinity of the tetrazolate anions towards
the [NiL2]2+ subunit is intermediate between that
of pyrazolate and the neutral diazine heterocy-
cles. There are no unusual features as far as bond
lengths and angles around the Ni atoms are con-
cerned. The average Ni–Namine and Ni–S distances
˚
are 2.239(2) and 2.4870(8) A, respectively. Similar
values have been observed in other Ni2 complexes
of L2− with N donor ligands [3] (see also Table 1).
Overall, the three structures clearly show that the
[Ni2L]2+ units can expand their binding pockets
sufficiently to accommodate 2,3-bridging tetrazolate
ligands.
CAUTION! Perchlorate salts are potentially explosive.
Only small quantities should be prepared and handled with
appropriate care.
Tetrazole (HCN4)
Glacial acetic acid (150 mL) was added with strong
stirring to a suspension of ammonium chloride (26.75 g,
0.5 mol), sodium azide (39.1 g, 0.55 mol) and triethylortho-
formate (150 mL, 0.9 mol). The mixture was stirred on a boil-
ing water bath for 2.5 – 3 h. Then the reaction mixture was
cooled to r. t., treated with concentrated hydrochloric acid
(7 – 10 mL) and filtered. The filtrate was evaporated to dry-
ness on a rotary evaporator, and the residue was washed with
dichloromethane and recrystallized from acetic acid. Yield:
25.2 g (72 %). M. p. 154 – 156 ◦C.
Conclusion
A series of novel dinuclear nickel(II) tetrazolate
complexes supported by a hexaaza-dithiophenolate
ligand have been synthesized and characterized,
namely [Ni2L(HCN4)]+ (2), [Ni2L(MeCN4)]+ (3),
and [Ni2L(PhCN4)]+ (4). The crystal structures of the
tetraphenylborate salts confirm the presence of 2,3-
bridging tetrazolate units showing that the [Ni2L]2+
units can expand their binding pockets sufficiently to
accommodate these ligands. Future work is focused on
transformations of the tetrazolate moieties in the pock-
ets of the complexes.
[Ni2L(HCN4)][ClO4] (2[ClO4])
To a solution of tetrazole (15.4 mg, 0.220 mmol)
in methanol (30 mL) was added triethylamine (22 mg,
0.22 mmol). Complex 1[ClO4] (184 mg, 0.20 mmol) was
added and the resulting green solution stirred for 12 h. A
Unauthenticated
Download Date | 11/15/15 9:16 AM

500
V. Lozan et al. · Macrocyclic Dinickel Complexes
solution of LiClO4 · 3H2O (321 mg, 2.00 mmol) in methanol comp.). – IR (KBr): ν = 3443 (s), 3055 (m), 3033 (m), 2998
(5 mL) was then added to the green solution. After further (m), 2964 (s), 2866 (s), 1940 (w), 1817 (w), 1631 (w), 1580
stirring for 2 h, the green precipitate was filtered off, washed (m), 1485 (s), 1461 (s), 1427 (m), 1395 (w), 1363 (m), 1309
with cold ethanol, and dried in air. Yield: 156 mg (82 %). (w), 1291 (w), 1264 (m), 1235 (m), 1199 (w), 1169 (w),
M. p. 352 – 353 ◦C (decomp.). – IR (KBr): ν = 3442 (s), 1153 (w), 1134 (m), 1110 (w), 1075 (s), 1056 (s), 1041 (s),
2962 (s), 2868 (s), 2022 (w), 1632 (m), 1463 (s), 1428 (m), 1000 (w), 982 (w), 929 (w), 912 (m), 882 (w), 843 (w), 825
1395 (w), 1363 (m), 1311 (w), 1264 (w), 1235 (w), 1200 (m), 807 (w), 733 (s, ν(BPh4−)), 704 (s, ν(BPh4−)), 669
(m), 1169 (w), 1153 (m), 1120 (s), 1098 (vs, ν3(ClO4−)), (w), 630 (m), 612 (m), 564 (w), 543 (w), 493 (w), 470 (w),
1056 (s), 1040 (s), 1013 (w), 999 (w), 983 (w), 930 (w), 913 417 (w) cm−1. – UV/Vis (MeCN): λmax (ε, mol−1 cm−1) =
(m), 882 (w), 826 (m), 808 (w), 755 (w), 702 (w), 624 (m, 267 (19980), 275 (18131), 294 (sh, 13715), 334 (11203), 382
ν4(ClO4−)), 565 (w), 544 (w), 493 (w), 418 (w) cm−1. – (2349), 620 (25), 1128(57) nm. – Elemental analysis (%)
UV/Vis (MeCN): λmax (ε, mol−1 cm−1) = 265 (sh, 17150), for C64H87BN10Ni2S2 (1188.77): calcd. C 64.66, H 7.38,
302 (sh, 13305), 334 (11220), 380 (2364), 620 (31), 1135 N 11.78, S 5.39; found C 63.47, H 7.30, N 12.05, S 4.62.
(64) nm.
[Ni2L(PhCN4)][ClO4] (4[ClO4])
[Ni2L(HCN4)][BPh4] (2[BPh4])
This compound was prepared in analogy to 2[ClO4] us-
A solution of NaBPh4 (342 mg, 1.00 mmol) in methanol ing 5-phenyltetrazole in place of tetrazole. Yield: 161 mg
(5 mL) was added to a solution of 2[ClO4] (96 mg, (78 %). M. p. 356 – 357 ◦C (decomp.). – IR (KBr): ν = 3442
0.100 mmol) in methanol (50 mL) and stirred for 3 h at am- (s), 2964 (s), 2901 (m), 2868 (s), 2023 (w), 1630 (m), 1462
bient temperature. The green solid was filtered, washed with (s), 1395 (w), 1363 (m), 1310 (w), 1264 (m), 1235 (m), 1201
ethanol and dried in air to give 107 mg (91 %) of 2[BPh4] (w), 1171 (w), 1154 (m), 1120 (s), 1099 (vs, ν3(ClO4−)),
as a green, air-stable, microcrystalline powder. M. p. 305 – 1056 (s), 1040 (s), 1010 (w), 999 (w), 983 (w), 930 (w), 913
306 ◦C (decomp.). – IR (KBr): ν = 3442 (s), 3055 (m), 3033 (w), 882 (w), 827 (m), 808 (w), 786 (w), 753 (w), 732 (w),
(m), 2999 (m), 2965 (s), 2866 (s), 1940 (w), 1816 (w), 1631 695 (m), 624 (m, ν4(ClO4−)), 565 (w), 545 (w), 492 (w), 418
(m), 1580 (m), 1481 (s), 1461 (s), 1427 (m), 1395 (w), 1363 (w) cm−1. – UV/Vis (CH3CN): λmax (ε, mol−1 cm−1) = 268
(m), 1309 (w), 1265 (m), 1235 (m), 1201 (w), 1168 (m), (18400), 300 (sh, 13775), 334 (11172), 384 (2334), 620 (28),
1153 (w), 1110 (w), 1074 (s), 1056 (s), 1040 (s), 999 (w), 1128 (61) nm.
982 (w), 929 (m), 912 (w), 883 (m), 844 (w), 825 (m), 808
(w), 748 (m), 733 (s, ν(BPh4−)), 704 (s, ν(BPh4−)), 668
(w), 630 (m), 612 (m), 564 (w), 543 (w), 493 (w), 468 (w),
416 (w) cm−1. – UV/Vis (MeCN): λmax (ε, mol−1 cm−1) =
266 (20520), 275 (18490), 302 (sh, 13557), 334 (11384), 380
(2418), 623 (30), 1132 (63) nm. – Elemental analysis (%)
for C63H85BN10Ni2S2 (1174.74): calcd. C 64.41, H 7.29,
N 11.92, S 5.46; found C 63.85, H 7.78, N 12.06, S 5.57.
[Ni2L(PhCN4)][BPh4] (4[BPh4])
This compound was prepared in analogy to 2[BPh4].
Yield: 112 mg (90 %). M. p. 298 – 299 C (decomp.). – IR
◦
(KBr): ν = 3442 (s), 3054 (m), 3031 (m), 2998 (s), 2964
(m), 2865 (s), 2812 (m), 1946 (w), 1882 (w), 1815 (w), 1630
(m), 1580 (m), 1461 (s), 1427 (m), 1395 (w), 1363 (m), 1308
(w), 1291 (w), 1265 (m), 1235 (m), 1200 (w), 1170 (w),
1153 (m), 1125 (w), 1110 (w), 1074 (s), 1055 (s), 1041 (s),
1010 (w), 999 (w), 982 (w), 929 (m), 912 (w), 882 (w), 843
[Ni2L(MeCN4)][ClO4] (3[ClO4])
This compound was prepared in analogy to 2[ClO4] using (w), 825 (m), 807 (w), 785 (w), 732 (s, ν(BPh4−)), 704 (s,
5-methyltetrazole in place of tetrazole. Yield: 155 mg (80 %). ν(BPh4−)), 669 (w), 629 (m), 612 (m), 565 (w), 543 (w),
M. p. 362 – 363 ◦C (decomp.). – IR (KBr): ν = 3443 (s), 2958 492 (w), 470 (w), 417 (w) cm−1. – UV/Vis (CH3CN): λmax
(s), 2869 (s), 2023 (w), 1631 (m), 1487 (s), 1462 (s), 1395 (ε, mol−1 cm−1) = 263 (sh, 23040), 274 (16320), 298 (sh,
(w), 1364 (m), 1310 (w), 1264 (m), 1235 (m), 1200 (w), 1153 11953), 334 (9607), 384 (2032), 616 (30), 1132 (59) nm. –
(m), 1120 (s), 1099 (vs, ν3(ClO4−)), 1078 (s), 1056 (s), 1041 Elemental analysis (%) for C69H89BN10Ni2S2 (1250.84):
(s), 1001 (w), 983 (w), 930 (w), 913 (w), 881 (w), 827 (m), calcd. C 66.25, H 7.17, N 11.20, S 5.13; found C 66.15,
818 (m), 808 (w), 754 (w), 704 (w), 625 (m, ν4(ClO4−)), 565 H 7.25, N 11.37, S 4.91.
(w), 543 (w), 493 (w), 418 (w) cm−1. – UV/Vis (MeCN):
λmax (ε, mol−1 cm−1) = 275 (sh, 13743), 300 (sh, 8958),
Crystal structure determination
334 (7300), 386 (1544), 616 (23), 1132 (45) nm.
Single crystals of 2[BPh4] · MeCN, 3[BPh4] · 2MeCN and
4[BPh4] · MeCN were grown by recrystallization from ace-
[Ni2L(MeCN4)][BPh4] (3[BPh4])
tonitrile. The data sets were collected at 213(2) K using a
The preparation of this compound was similar to that used Stoe IPDS-2T diffractometer and graphite-monochromated
◦
˚
for 2[BPh4]. Yield: 106 mg (89 %). M. p. 333 – 334 C (de- MoKα radiation (λ = 0.71073 A). The intensity data were
Unauthenticated
Download Date | 11/15/15 9:16 AM

V. Lozan et al. · Macrocyclic Dinickel Complexes
501
Table 2. Crystallographic data for 2[BPh4] · MeCN, 3[BPh4] · 2MeCN, and 4[BPh4] · MeCN.
Compound
2[BPh4] · MeCN
3[BPh4] · 2MeCN
4[BPh4] · MeCN
Formula
Mr
C65H88BN11Ni2S2
1215.81
P1
C68H93BN12Ni2S2
1270.89
P21/c
15.060(2)
27.916(3)
16.658(2)
90
107.01(2)
90
6697.0
C71H92BN11Ni2S2
1291.91
P2/c
¯
Space group
˚
a, A
13.265(1)
15.730(1)
16.941(1)
108.630(3)
92.22(3)
107.46(2)
3159.7(4)
2
30.253(6)
13.221(2)
38.202(12)
90
110.19(2)
90
14341(6)
8
1.197
˚
b, A
˚
c, A
α, deg
β, deg
γ, deg
3
˚
V, A
Z
4
dcalcd., g cm−3
Cryst. size, mm3
µ(MoKα ), mm−1
θ limits, deg
1.278
1.260
0.20×0.20×0.20
0.20×0.20×0.20
0.25×0.20×0.15
0.711
0.674
0.630
2.04 – 26.06
25362
11582
8335
786
0.029 (0.070)
0.041 (0.072)
0.32/−0.26
1.76 – 26.81
50262
14192
8783
766
1.71 – 24.63
84185
23998
15689
1622
0.049 (0.119)
0.084 (0.131)
1.25/−0.44
Measured refl.
Independent refl.
Observed refl.a
No. parameters
R1a,b (R1 all data)
wR2a,c (wR2 all data)
0.048 (0.089)
0.099 (0.092)
0.73/−0.34
−3
˚
∆ρfin (max/min), e A
a
b
c
2
Observation criterion: I ≥ 2σ(I);
R1 = ΣꢁFo|−|Fcꢁ/Σ|Fo|;
wR2 = {Σ[w(Fo −Fc2)2]/Σ[w(Fo2)2]}1/2. ns2
processed with the program Stoe X-AREA. Structures were located unambiguously from final Fourier maps. Drawings
solved by Direct Methods [23] and refined by full-matrix were produced with ORTEP-III for Windows [26].
least-squares on the basis of all data against F2 using
CCDC
673545
(2[BPh4]2 · MeCN),
673546
SHELXL-97 [24]. PLATON was used to search for higher (3[BPh4] · 2MeCN), and 673547 (4[BPh4]2 · 2MeCN)
symmetry [25]. H atoms were placed at calculated positions contain the supplementary crystallographic data for this
and refined as riding atoms with isotropic displacement pa- paper. These data can be obtained free of charge from the
rameters. All non-hydrogen atoms were refined anisotropi- Cambridge Crystallographic Data Centre via www.ccdc.cam
cally. Selected crystallographic data are summarized in Ta- .ac.uk/data request/cif.
ble 2.
Acknowledgements
In the crystal structures of 2[BPh4] · MeCN and
We are grateful to Prof. Dr. H. Krautscheid for provid-
ing facilities for X-ray crystallographic measurements. This
work was supported by the Deutsche Forschungsgemein-
schaft (Priority programme “Sekunda¨re Wechselwirkungen”,
4[BPh4] · MeCN two tert-butyl groups were found to be
rotationally disordered. This disorder was refined by a
split atom model yielding occupancy factors of 0.55/0.45,
0.56/0.44 (for 2), 0.36/0.64 and 0.50/0.50 (for 4), respec-
tively. For 2[BPh4] · MeCN, the hydrogen atom H(39) was
KE 585/3-3) and the University of Leipzig.
[1] B. Kersting, G. Steinfeld, Chem. Commun. 2001,
1376 – 1377.
[2] M. H. Klingele, G. Steinfeld, B. Kersting, Z. Natur-
forsch. 2001, 56b, 901 – 907.
[3] J. Hausmann, V. Lozan, M. H. Klingele, G. Steinfeld,
D. Siebert, Y. Journaux, J. J. Girerd, B. Kersting, Chem.
Eur. J. 2004, 10, 1716 – 1728.
[6] B. Kersting, G. Steinfeld, Inorg. Chem. 2002, 41,
1140 – 1150.
[7] G. Steinfeld, V. Lozan, B. Kersting, Angew. Chem.
2003, 115, 2363 – 2365; Angew. Chem. Int. Ed. 2003,
42, 2261 – 2263.
[8] V. Lozan, A. Buchholz, W. Plass, B. Kersting, Chem.
Eur. J. 2007, 13, 7305 – 7316.
[4] Y. Journaux, J. Hausmann, V. Lozan, B. Kersting,
Chem. Commun. 2006, 83 – 84.
[5] B. Kersting, Angew. Chem. 2001, 113, 4109 – 4112;
Angew. Chem. Int. Ed. 2001, 40, 3987 – 3990.
[9] J. Klingele, M. H. Klingele, O. Baars, V. Lozan,
A. Buchholz, G. Leibeling, W. Plass, F. Meyer, B. Ker-
sting, Eur. J. Inorg. Chem. 2007, 5277 – 5285.
[10] V. Lozan, B. Kersting, Inorg. Chem., submitted.
Unauthenticated
Download Date | 11/15/15 9:16 AM

502
V. Lozan et al. · Macrocyclic Dinickel Complexes
[11] B. Kersting, Z. Anorg. Allg. Chem. 2004, 630, 765 –
780.
Int. Ed. 2007, 46, 1419 – 1422; J. Tao, Z.-J. Ma, R.-B.
Huang, L.-S. Zheng, Inorg. Chem. 2004, 43, 6133 –
6135.
[12] V. Lozan, B. Kersting, Eur. J. Inorg. Chem. 2007,
1436 – 1443.
[19] S. F. Palopoli, S. J. Geib, A. L. Rheingold, T. B. Brill,
Inorg. Chem. 1988, 27, 2963 – 2971; S. Bhandari,
M. F. Mahon, K. C. Molloy, J. S. Palmer, S. F. Say-
ers, J. Chem. Soc., Dalton Trans. 2000, 1053 – 1060;
M. Dinca˘, A. F. Yu, J. R. Long, J. Am. Chem. Soc. 2006,
128, 8904 – 8913.
[20] M. Gressenbuch, B. Kersting, Eur. J. Inorg. Chem.
2007, 90 – 102.
[21] R. Goddard, O. Heinemann, C. Kru¨ger, Acta Crystal-
logr. 1997, C53, 590 – 592.
[13] Comprehensive Heterocyclic Chemistry II, Vol. 3, 4,
(Eds. A. R. Katritzky, C. W. Rees, E. F. V. Scriven),
Pergamon Press, Oxford, New York 1996.
[14] P. N. Gaponik, S. V. Voitekhovich, O. A. Ivashkevich,
Russ. Chem. Rev. 2006, 75, 507 – 539; A. P. Sadi-
menko, Adv. Heterocycl. Chem. 2002, 83, 117 – 187;
D. S. Moore, S. D. Robinson, Adv. Inorg. Chem. 1988,
32, 171 – 239; A. I. Popov, Coord. Chem. Rev. 1969, 4,
463 – 474.
[15] P. N. Gaponik, V. P. Karavai, Vestnik Belorus. Gos.
Univ., Ser. Khim. 1980, No. 3, 51 – 52; Patent US
3767667, 1973.
[22] Y. Ohno, Y. Akutsu, M. Arai, M. Tamura, T. Mat-
sunaga, Acta Crystallogr. 1999, C55, 1014 – 1016.
[23] G. M. Sheldrick, Acta Crystallogr. 1990, A46, 467 –
473.
[24] G. M. Sheldrick, SHELXL-97, Program for the Refine-
ment of Crystal Structures, University of Go¨ttingen,
Go¨ttingen (Germany) 1997.
[16] W. G. Finnegan, R. A. Henry, R. Lofquist, J. Am. Chem.
Soc. 1958, 80, 3908 – 3911.
[17] L. H. Gade, Koordinationschemie, (1st ed.), Wiley-
VCH, Weinheim 1998.
[18] E. O. John, R. D. Willet, B. Scott, R. L. Kirchmeier,
J. M. Shreeve, Inorg. Chem. 1989, 28, 893 – 897; E. O.
John, R. L. Kirchmeier, J. M. Shreeve, Eur. J. Solid
State Inorg. Chem. 1992, 29, 873 – 885; Z.-H. Shao,
J. Luo, R.-F. Cai, X.-G. Zhou, L.-H. Weng, Z.-X. Chen,
Acta Crystallogr. 2004, E60, m225 – m227; M. Dinca˘,
W. S. Han, Y. Liu, A. Dailly, C. M. Brown, J. R. Long,
Angew. Chem. 2007, 119, 1441 – 1444; Angew. Chem.
[25] A. L. Spek, PLATON, A Multipurpose Crystallographic
Tool, Utrecht University, Utrecht (The Netherlands)
2000. See also: A. L. Spek, J. Appl. Cryst. 2003, 36,
7 – 13.
[26] C. K. Johnson, M. N. Burnett, ORTEP-III (version
1.0.2), Rep. ORNL-6895, Oak Ridge National Labo-
ratory, Oak Ridge, TN (USA) 1996. Windows version;
L. J. Farrugia, J. Appl. Crystallogr. 1997, 30, 565.
Unauthenticated
Download Date | 11/15/15 9:16 AM