Synthesis and Reactivity of Nickel(II) Complexes of the Pyridine-Based Phosphorus-Containing Macrocycle 6-Phenyl-15-aza-6-phospha-3,9-dithiabicycio[9,3,1]pentadeca-1(15),11,13-triene

Article abstract of DOI:10.1021/ic9714753

The reactivity of the phosphomacrocycle 6-phenyl-15-aza-6-phospha-3,9-dithiabicyclo[9,3,1]pentadeca-1(15), 11,13-triene (L) toward different Ni(II) salts has been studied. The reaction of L with 1 molar equiv of Ni(II) perchlorate in acetonitrile solution gives the complex [Ni(L)(CH₃CN)₂](ClO₄)₂ (1), which crystallizes in the monoclinic space group P2₁/c (No. 14) with a = 12.704(2) ?, b = 13.538(2) ?, c = 17.377(2) ?, β = 107.554(8)°, and Z = 4. The Ni(II) atom in 1 shows an octahedral environment defined by the four donor atoms of L and two acetonitrile molecules in a cis disposition. The reaction of L with Ni(II) perchlorate in 2:1 molar ratio yields the green complex [Ni(Lox)₂](ClO₄)₂ (2) in which the phosphine groups of the ligand L are in their phosphine-oxide form (Lox). The same complex is also obtained by adding more ligand L to an acetonitrile solution of 1. Complex 2 crystallizes in the triclinic space group P1? (No. 2) with a = 10.564(1) ?, b = 11.975(2) ?, c = 9.124(2) ?, α = 109.79(1)°, β = 95.67(2)°, γ = 109.19(1)°, and Z = 1. The octahedral coordinated Ni(II) atom in 2 lies on a crystallographic center of symmetry, and it is surrounded by two pyridine nitrogen atoms, two thioether sulfur atoms, and two phosphine-oxide oxygen atoms provided by two facially coordinated Lox ligands. The reaction of L with Ni(II) chloride and Ni(II) thiocyanate yields the complexes [NiCl₂(L)] (3) and [Ni(NCS)₂(L)] (4), respectively, which are also obtained by adding Me₄NCl or KSCN to an acetonitrile solution of 1. Complex 4 crystallizes in the monoclinic space group P2₁/n (No. 14), with a = 11.139(2) A°, b = 13.270(2) A°, c = 14.885(1) A°, β = 92.34(1)°, and Z = 4. and its structure is similar to that of complex 1, simply replacing the two acetonitrile molecules by two SCN^- anions. The reactions of the complex 1 with different chelating (en, bipy, o-phen) and nonchelating (py) N-donor ligands have also been carried out. In all cases the two acetonitrile molecules of 1 are easly replaced by the N-donor ligands, but the macrocycle L molecule remains coordinated to the Ni(II) atom. The crystal structure of the complex [Ni(L)(py)₂](ClO₄)₂ (5) is also elucidated. Crystal data: monoclinic space group P2₁/c (No. 14) a = 13.063(2) A°, b = 16.615(3) A°, c = 14.973(3) A°, β = 91.76(2)°, Z = 4.

Full text of DOI:10.1021/ic9714753

Inorg. Chem. 1998, 37, 4807-4813
4807
Synthesis and Reactivity of Nickel(II) Complexes of the Pyridine-Based
Phosphorus-Containing Macrocycle 6-Phenyl-15-aza-6-phospha-3,9-
dithiabicyclo[9,3,1]pentadeca-1(15),11,13-triene
Lluis Escriche,*,† Jose´ Antonio Mun˜oz,† Joan Rosell,† Raikko Kiveka1s,‡ Reijo Sillanpa1a1,§ and
Jaume Casabo´†
Facultat de Cie`ncies (Cn), Departament de Qu´ımica (Unit. Inorga`nica), Universitat Auto`noma de
Barcelona, E-08193 Bellaterra, Barcelona, Spain, Department of Chemistry, P.O. Box 55,
University of Helsinki, FIN-00014 Helsinki, Finland, and Department of Chemistry,
University of Turku, FIN-20500 Turku, Finland
ReceiVed NoVember 20, 1997
The reactivity of the phosphomacrocycle 6-phenyl-15-aza-6-phospha-3,9-dithiabicyclo[9,3,1]pentadeca-1(15),
11,13-triene (L) toward different Ni(II) salts has been studied. The reaction of L with 1 molar equiv of Ni(II)
perchlorate in acetonitrile solution gives the complex [Ni(L)(CH3CN)2](ClO4)2 (1), which crystallizes in the
monoclinic space group P21/c (No. 14) with a ) 12.704(2) Å, b ) 13.538(2) Å, c ) 17.377(2) Å, â )
107.554(8)°, and Z ) 4. The Ni(II) atom in 1 shows an octahedral environment defined by the four donor atoms
of L and two acetonitrile molecules in a cis disposition. The reaction of L with Ni(II) perchlorate in 2:1 molar
ratio yields the green complex [Ni(Lox)2](ClO4)2 (2) in which the phosphine groups of the ligand L are in their
phosphine-oxide form (Lox). The same complex is also obtained by adding more ligand L to an acetonitrile
solution of 1. Complex 2 crystallizes in the triclinic space group P1h (No. 2) with a ) 10.564(1) Å, b )
11.975(2) Å, c ) 9.124(2) Å, R ) 109.79(1)°, â ) 95.67(2)°, γ ) 109.19(1)°, and Z ) 1. The octahedral
coordinated Ni(II) atom in 2 lies on a crystallographic center of symmetry, and it is surrounded by two pyridine
nitrogen atoms, two thioether sulfur atoms, and two phosphine-oxide oxygen atoms provided by two facially
coordinated Lox ligands. The reaction of L with Ni(II) chloride and Ni(II) thiocyanate yields the complexes
[NiCl2(L)] (3) and [Ni(NCS)2(L)] (4), respectively, which are also obtained by adding Me4NCl or KSCN to an
acetonitrile solution of 1. Complex 4 crystallizes in the monoclinic space group P21/n (No. 14), with a )
11.139(2) Å, b ) 13.270(2) Å, c ) 14.885(1) Å, â ) 92.34(1)°, and Z ) 4, and its structure is similar to that of
complex 1, simply replacing the two acetonitrile molecules by two SCN- anions. The reactions of the complex
1 with different chelating (en, bipy, o-phen) and nonchelating (py) N-donor ligands have also been carried out.
In all cases the two acetonitrile molecules of 1 are easly replaced by the N-donor ligands, but the macrocycle L
molecule remains coordinated to the Ni(II) atom. The crystal structure of the complex [Ni(L)(py)2](ClO4)2 (5)
is also elucidated. Crystal data: monoclinic space group P21/c (No. 14) a ) 13.063(2) Å, b ) 16.615(3) Å,
c ) 14.973(3) Å, â ) 91.76(2)°, Z ) 4.
Introduction
behave as neutral carriers in all-solid-state ion-selective elec-
trodes discriminating Cu(II) from Ni(II) and Co(II).1d These
In the last years we have reported the synthesis and com-
plexing behavior of several macrocyclic and open-chain ligands
containing the NS2 donor group which is present in the 2,6-
bis(thiomethyl)pyridine unit.1,2 In these papers we have dem-
onstrated that some of the studied NS2-based macrocycles
results encouraged us to study the coordinating abilities of new
macrocycles containing the 2,6-bis(thiomethyl)pyridine unit, and
we have recently reported the synthesis of the phosphine
containing macrocycle 6-phenyl-15-aza-6-phospha-3,9-dithiabi-
cyclo[9,3,1]pentadeca-1(15),11,13-triene (L in Scheme 1).3 The
chemistry of phosphomacrocycles has been comparatively less
developed than that of their oxygen, nitrogen, or sulfur
* Corresponding author.
† Universitat Auto`noma de Barcelona.
‡ University of Helsinki.
§ University of Turku.
(1) (a) Teixidor, F.; Escriche, L.; Casabo´, J.; Molins, E.; Miravitlles, C.
Inorg. Chem. 1986, 25, 4060. (b) Teixidor, F.; Escriche, L.; Rodriguez,
I.; Casabo´, J.; Rius, J.; Molins, E.; Martinez, B.; Miravitlles, C. J.
Chem. Soc., Dalton Trans. 1989, 1381. (c) Escriche, L.; Sanz, M.;
Casabo´, J.; Teixidor, F.; Molins, E.; Miravitlles, C. J. Chem. Soc.,
Dalton Trans. 1989, 1739. (d) Casabo´, J.; Escriche, L.; Alegret, S.;
Jaime, C.; Pe´rez-Jime´nez, C.; Mestres, L.; Rius, J.; Molins, E.;
Miravitlles, C.; Teixidor, F. Inorg. Chem. 1991, 30, 1893. (e) Teixidor,
F.; Sa´nchez-Castello´, G.; Lucena, N.; Escriche, L.; Kiveka¨s, R.;
Sundberg, M.; Casabo´, J. Inorg. Chem. 1991, 30, 4931. (f) Teixidor,
F.; Sa´nchez-Castello´, G.; Lucena, N.; Escriche, L.; Kiveka¨s R.; Casabo´,
J. J. Chem. Soc., Chem. Commun. 1992, 163. (g) Sillanpa¨a¨, R.;
Kiveka¨s, R.; Escriche, L.; Casabo´ J.; Sa´nchez-Castello´, G. Acta
Crystallogr. 1994, C50, 1062.
(2) Other studies on PyS2 ligands: (a) Vo¨gtle F.; Ley, F. Chem. Ber. 1983,
116, 3000. (b) Parker, D.; Lehn, J. M.; Rimmer, J. J. Chem. Soc.,
Dalton Trans. 1985, 1517. (c) Carroy, A.; Lehn, J. M. J. Chem. Soc.,
Chem. Commun. 1986, 1232. (d) Ferguson, G.; Matthes, K. E.; Parker,
D.; Ang. Chem., Int. Ed. Engl. 1987, 26, 1162. (e) Gunter, M. J.;
Mander, L. N.; Murray, K. S.; Clark, P. E. J. Am. Chem. Soc. 1981,
103, 6784. (f) Salata, C. A.; Van Engen, D.; Burrows, C. J. J. Chem.
Soc., Chem. Commun. 1988, 579. (g) Helps, I. M.; Matthes, K. E.;
Ferguson, G. J. Chem. Soc., Dalton Trans. 1989, 915. (h) Girmay,
B.; Kilburn, J. D.; Underhill, A. E.; Varma, K. S.; Hursthouse, M. B.;
Harman, M. E.; Becher, J.; Bojesen, G. J. Chem. Soc., Chem. Commun.
1989, 1406.
(3) Mun˜oz, J. A.; Escriche, L.; Pe´rez-Jime´nez, C.; Casabo´, J.; Kiveka¨s,
R.; Sillanpa¨a¨, R. Inorg. Chim. Acta 1997, 257, 99.
S0020-1669(97)01475-4 CCC: $15.00 © 1998 American Chemical Society
Published on Web 09/03/1998

4808 Inorganic Chemistry, Vol. 37, No. 19, 1998
Escriche et al.
Scheme 1
equivalents.4 However, the potential catalytic activity of the
metal complexes of these ligands and the documented capability
of their phosphoryl5,6 and thiophosphoryl7 derivatives to interact
selectively with ionic species increases the interest in the
synthesis of new phosphomacrocycles. In this context we expect
that the NS2P macrocycle L, which combines hard and soft
donor atoms, could exhibit interesting coordinating properties
toward first and second row transition metal ions. As an
additional point of interest, ligands containing N, S, and P mixed
donor atoms have been recently used as models in the study of
redox processes involved in Ni-containing biological systems.8
In this paper we report on the reaction products of the NS2P
macrocyclic ligand L with different Ni(II) salts and their
reactivity in front of anionic and neutral N-donor ligands.
Reactions of L with Ni(ClO4)2‚6H2O. The reaction at open
atmosphere of equimolar amounts of ligand L and Ni(ClO4)2‚
6H2O in acetonitrile solution yields a violet air-stable solution.
Addition of diethyl ether to this solution causes precipitation
of compound 1 as violet crystals, whose elemental analysis fits
the formula Ni(ClO4)2(L)(CH3CN)2. This crystalline material,
which slowly turns opaque at room temperature, is soluble in
acetonitrile, acetone, and chloroform and behaves as a 2:1
electrolyte in acetonitrile solution. The IR spectrum shows a
strong band at 2302 cm-1 assigned to the acetonitrile CN
stretching. This band position, which is similar to that found
in other Ni-acetonitrile complexes,9,10 proves that the two
acetonitrile molecules are directly bound the Ni(II) ion. There-
fore, the complex 1 must be formulated as [Ni(L)(CH3CN)2]-
(ClO4)2, as has also been demonstrated by X-ray diffraction
analysis.
Results and Discussion
The reaction at open atmosphere of acetonitrile solutions of
ligand L and Ni(ClO4)2‚6H2O in a 2:1 molar ratio displays a
very different behavior to that described before. In this case
the reaction mixture turns green and, after addition of diethyl
ether, a green, air-stable, crystalline material appears which
corresponds to compound 2. This compound behaves as a 2:1
electrolyte in acetonitrile solution and its elemental analyses
indicate that the ligand L and Ni(ClO4)2 are present in a 2:1
The syntheses and molecular structures of the new complexes
are summarized in Scheme 1.
(4) Caminade, A. M.; Majoral, J. P. Chem. ReV. 1994, 94, 1183.
(5) Savage, P. B.; Holmgren, S. K.; Gellman, S. H. J. Am. Chem. Soc.
1994, 116, 4069.
(6) Casabo´, J.; Escriche, L.; Pe´rez-Jime´nez, C.; Mun˜oz, J. A.; Teixidor,
F.; Baucells, J.; Errachid, A. Anal. Chim. Acta 1996, 320, 63.
(7) (a) Sinyavskaya. E. I. Koord. Khim. 1986, 12, 1155. (b) Tsvetkov, E.
N.; Bovin, A. N.; Syundyukova, V. K. Russ. Chem. ReV. 1988, 776.
(c) Izatt, R. M.; Pawlak, K.; Bradshaw, J. S.; Bruening, R. L. Chem.
ReV. 1991, 91, 1721.
(9) Bourgon, R.; Charpin, P.; Christe, K. O.; Isabey, J.; Lance, M.;
Nierlich, M.; Vigner, J.; Wilson, W. W. Inorg. Chem. 1988, 27, 1389.
(10) Adhikary, B.; Liu, S.; Lucas, R. Inorg. Chem. 1993, 32, 5957.
(8) James, T. L.; Smith, D. M.; Holm, R. H. Inorg. Chem. 1994, 33, 4869.

Ni(II) Macrocycle Complexes
Inorganic Chemistry, Vol. 37, No. 19, 1998 4809
Figure 1. ORTEP plot of complex unit [Ni(L)(CH3CN)2]2+ of 1
showing 30% displacement ellipsoids. Hydrogen atoms are omitted for
clarity.
Figure 2. ORTEP plot of the complex unit [Ni(Lox)2]2+ of 2 showing
30% displacement ellipsoids. Hydrogen atoms are omitted for clarity.
molar ratio, without any solvent molecules, as it has been
confirmed by IR spectroscopy. It is interesting to note that the
green, 2:1 complex 2 is also obtained by reaction of equimolar
acetonitrile solutions of ligand L and the violet 1:1 complex 1.
Some discrepancies between the calculated and found analysis
suggested us that the ligand L in 2 is modified in this complex,
as it has been confirmed by X-ray diffraction analysis.
-
The crystal structure of 2 consists of discrete ClO4 anions
and [Ni(Lox)2]2+ complex cations where the ligand L exists in
its phosphine-oxide form (Lox). Figure 2 shows the molecular
structure and labeling scheme for [Ni(Lox)2]2+. The Ni(II) atom
occupies a crystallographic inversion center in a distorted
octahedral environment of two pyridine nitrogen atoms, two
thioether-sulfur atoms and two phosphine-oxide oxygen atoms
provided by two facially coordinating Lox ligands. Thus, each
Lox macrocyclic unit acts as a tridentate ligand using only three
of its four donor atoms and leaving one of the two thioether-
sulfur atoms uncoordinated. The Ni-S bond distances
(2.451(2) Å) are similar to that found in complex 1. However,
the Ni-N bond lengths (2.189(6) Å) are slightly longer that
the average distance found in other reported Ni(II)-pyridine
complexes8,10,11,14 (ca. 2.12 Å). The Ni-O and P-O bond
distances (2.022(2) and 1.515(5) Å, respectively) are comparable
to those found in the few octahedral Ni(II)-OPR3 complexes
reported yet in the literature.15 It is interesting to compare the
structure of [Ni(Lox)2]2+ described here with that found in the
cation [Co(Lox)2]2+, which we have previously reported in the
double complex salt [Co(Lox)2][CoCl3(Lox)]2.3 Both cation
complexes are essentially identical with small differences in the
M-N and M-S bond distances, which are slightly longer in
the Co(II) complex, as it was expected from the different ionic
radii of Ni(II) and Co(II).16 This fact evidences that the
noncoordinating behavior of the sulfur S(2) makes the Lox
ligand flexible enough to accommodate different metal cations
while maintaining the same sandwich-like structure.
Crystal Structures of 1 and 2. The crystal structure of 1
consists of discrete [Ni(L)(CH3CN)2]2+ cations and ClO4
-
anions without any significant interactions between them.
Figure 1 shows the molecular structure and labeling scheme
for [Ni(L)(CH3CN)2]2+. The coordination sphere of the Ni(II)
atom in this complex cation is a distorted octahedron defined
by two thioether sulfurs, the phosphine phosphorus and the
pyridine nitrogen atoms of the ligand L and two nitrogen atoms
from the acetonitrile molecules. The Ni-S distances
(2.442(3) Å) are scarcely longer than those found in related
Ni(II) macrocyclic complexes containing the 2,6-bis(thiometh-
yl)pyridine unit11 (ca. 2.39 Å) and closer to the typical values
for Ni(II)-thioether binding (ca. 2.42 Å).8,10,12 The Ni-N(L)
and the Ni-P bond lengths (2.082(6) and 2.342(2) Å, respec-
tively) are not significantly different from the found values in
related Ni(II) complexes.8,11 The two Ni-N(acetonitrile)
distances show slightly different values (2.090(7) and 2.023(7)
Å), as it has been observed in other bis(acetonitrile)-Ni(II)
complexes.10,13a,b However, there is no evidence to indicate a
different reactivity between the two coordinated acetonitrile
molecules, because both are easily replaced by other ligands
(see below). The major distortion in the octahedral geometry
around the Ni(II) atom is imposed by the meridional coordina-
tion of the 2,6-bis(thiomethyl)pyridine unit, as it is observed in
the value of the S1-Ni-S2 angle (163.61(9)°). The phosphine-
phosphorus atom is located perpendicularly to the plane defined
by the Ni(II), the N(L), and the two thioether-sulfur atoms,
which provides a folded conformation of the ligand L and leaves
the two acetonitrile molecules in a relative cis orientation. There
are in the literature several reported cases of bis(acetonitrile)-
Ni(II) complexes with tetradentate ligands showing the aceto-
nitrile molecules in a trans orientation;11a,13 however, the cis
disposition of these molecules seems to be less frequent.10
As mentioned above, the two macrocyclic ligands in complex
2 are in their phosphine-oxide form (Lox). This can be
explained by the reaction of the ligand L and the Ni(II) ion in
acetonitrile solution with atmospheric dioxygen, which promotes
the oxidation of the phosphine group. The same behavior was
observed in the reaction between the ligand L and CoCl2 in
acetonitrile solution, which yields the aforementioned compound
[Co(Lox)2][CoCl3(Lox)]2. However both reactions have dif-
ferent features. The ligand L oxidation in the Co(II) reaction
is a slow process (it is easely monitored by UV spectroscopy),
and not depends on the L:Co(II) stoichiometric ratio used. The
same process in the Ni(II) reaction is very fast, but only occurs
when the amount of ligand L exceed the 1:1 ligand-to-metal
ratio. Several phosphine-containing Co(II) complexes have been
(11) (a) Constable, E. C.; Lewis, J.; Marquez, V. E.; Raithby, P. R. J. Chem.
Soc., Dalton Trans. 1986, 1747. (b) Blake, A. J.; Demartin, F.;
Devillanova, F. A.; Garau, A.; Isaia, F.; Lippolis, V.; Schro¨der, M.;
Verani, G. J. Chem. Soc., Dalton Trans. 1996, 3705.
(12) Orpen, A. G.; Brammer, F. H.; Allen, O. K.; Watson, R. T. J. Chem.
Soc., Dalton Trans. 1989, Suppl. S1.
(13) (a) Jircitano, A. J.; Mertes, K. B. Inorg. Chem. 1983, 22, 1828. (b)
Freeman, G. M.; Barefield, E. K.; Van Derveer, D. G. Inorg. Chem.
1984, 23, 3092. (c) Oshio, H. Inorg. Chem. 1993, 32, 4123. (d)
Barefield, E. K.; Freeman, G. M.; Van Derveer, D. G. J. Chem. Soc.,
Chem. Commun. 1983, 1358.
(14) Funkemeier, D.; Mattes, R. J. Chem. Soc., Dalton Trans. 1993, 1313.
(15) (a) Polam, J. R.; Porter, L. C. Acta Crystallogr. 1992, C48, 1761. (b)
Dodof, N.; Macicek, J.; Angelova, O.; Varbanov, N.; Spassovska, N.
J. Coord. Chem. 1990, 22, 219.
(16) Shannon, R. D. Acta Crystallogr. 1976, A32, 751.

4810 Inorganic Chemistry, Vol. 37, No. 19, 1998
Escriche et al.
reported to display similar behavior toward dioxygen.17 Even,
a mechanism involving the initial formation of a Co(II)-dioxygen
adduct has been suggested to explain the observed ligand
oxidation.17b However, we have not found in the literature
examples of this type of oxidation reactions involving phos-
phine-containing Ni(II) complexes.
Reactions of L with NiCl2‚6H2O and Ni(SCN)2‚H2O. The
reaction of equimolar amounts of ligand L and NiCl2‚6H2O or
Ni(SCN)2‚H2O in acetonitrile solution gives the air-stable,
nonelectrolyte products 3 and 4, respectively. Both compounds
are less solubles in acetonitrile than 1 and 2, and they are also
obtained by adding (Me4N)Cl and KSCN, respectively, to an
acetonitrile solution of 1. These data suggest that the molecular
structure of both compounds is similar to that described for the
complex 1 simply replacing the acetonitrile coordinated mol-
ecules by the anionic ligands. This assumption has been
confirmed by the X-ray diffraction analysis of the compound 4
(see below). It is interesting to note that these reactions seem
not to be depending on the used L:Ni(II) stoichiometric ratio.
All the experiences made using different metal-to-ligand ratio
gave as final products the compounds 3 and 4, and no evidences
of oxidation products have been found. This behavior is in
contrast with that described in the reactivity of the ligand L in
front of Ni(ClO4)2. The reason could be the low solubility and
neutral character of the compounds 3 and 4 which increase their
stability and prevent the oxidation of the ligand L.
Figure 3. ORTEP plot of the complex [Ni(NCS)2(L)] 4 showing 20%
displacement ellipsoids. Hydrogen atoms are omitted for clarity.
Reactions of 1 with N-Donor Ligands. The previously
described reactivity evidences the lability of the acetonitrile
ligands in complex 1. In addition, the new complexes seem to
retain the macrocyclic ligand L coordinated to the Ni(II) ion
which reflects the stability of the (L)Ni(II) coordinated unit.
To confirm this assumption, several reactions between the
complex 1 and different chelating and nonchelating N-donor
ligands have been carried out.
Figure 4. ORTEP plot of the complex unit [Ni(L)(py)2]2+ of 5 showing
20% displacement ellipsoids. Hydrogen atoms are omitted for clarity.
Table 1. Electronic Spectral Data
a
complex
λ
max, nm (ꢀ, L mol-1 cm-1
)
∆o, cm-1
1
2
3
4
6
7
8
905 (sh), 828 (106), 542 (38)
915 (sh), 844 (65), 539 (30)
970 (sh), 940 (88), 582 (20)
975 (sh), 930 (95), 575 (37)
950 (sh), 918 (62), 592 (25)
983 (sh), 911 (75), 592 (33), 525 (sh)
979 (sh), 915 (60), 594 (43), 531 (sh)
12 077
11 848
10 638
10 753
10 893
10 977
10 929
The reaction of equimolar amounts of the complex 1 and
pyridine in acetonitrile solution yields the green, air stable
complex 5. The crystal structure of this compound (see below)
confirms that the acetonitrile ligands of 1 have been replaced
by two pyridine molecules while the (L)Ni(II) unit remains
unchanged. The complex 5 redissolves in acetonitrile, producing
a violet solution, the electronic spectra of which are coincident
with that obtained from acetonitrile solutions of 1. This fact
evidences the lability of the pyridine ligands in 5, which are
displaced to regenerate the complex 1, in excess of acetonitrile.
A method similar to synthesize the complex 5 has been used
to obtain the compounds 6-8. Complex 1 reacts with aliphatic
(ethylenediamine) or aromatic (o-phenantroline and bipyridine)
N-donor chelating ligands, giving the colored, air-stable com-
pounds 6, 7, and 8, respectively. All of them behave as 2:1
electrolytes in acetonitrile solution, and their elemental analysis
and IR spectra prove that their molecular structures are similar
to that described for 1, simply replacing the two acetonitrile
molecules by the chelating ligand. These complexes are less
soluble in acetonitrile than the complex 5, and no evidence of
ligand exchange reactions has been observed in solution. This
confirms that the chelating nature of these N-donor ligands
stabilizes the complexes 6-8 and prevents further reactions.
Crystal Structures of 4 and 5. The crystal structure of the
complex 4 consists of discrete [Ni(NCS)2(L)] molecules,
a In CH3CN.
and labeling schemes for [Ni(NCS)2(L)] and [Ni(L)(py)2]2+
,
respectively. In both cases the coordination geometry of the
Ni(II) atom is a distorted octahedron defined by the four donor
atoms of the ligand L and the nitrogen atoms of the two SCN-
ions in 4 or the two pyridine molecules in 5. The arrangement
of these ligands around the Ni(II) atoms is similar to that
described for the complex 1, so the two monodentate ligands
of each compound have a relative cis orientation. The Ni-
N(L) and the two Ni-S distances in 4 (2.108(2), 2.4784(8),
and 2.4566(8) Å, respectively) and 5 (2.123(5), 2.515(2), and
2.468(2) Å, respectively) are slightly longer than those for 1.
However, the Ni-P bond distances in 1 and 5 (2.343(2) and
2.342(2) Å, respectively) are equal, whereas in 4 (2.3669(7)
Å) it is slightly longer. The Ni-N(pyridine) (compound 5) and
Ni-N(thiocyanate) bond lengths exhibit values comparable to
the average distances reported in the literature12 (ca. 2.12 and
2.06 Å, respectively). As in complex 1, distortion in the Ni(II)
octahedral geometry of 4 and 5 is also manifested by the value
of the S-Ni-S bond angle (166.33(3) and 159.91(6)°, respec-
tively), which confirms the strain imposed to the ligand L by
the meridional coordination of the 2,6-bis(thiomethyl)pyri-
dine unit.
-
whereas that of the complex 5 contains ClO4 anions and
[Ni(L)(py)2]2+ complex cations without significant interactions
between them. Figures 3 and 4 show the molecular structures
(17) (a) Schmidt, D. D.; Yoke, J. T. J. Am. Chem. Soc. 1971, 93, 637. (b)
Hwang, W.; Joedicke, I. B.; Yoke, J. T. Inorg. Chem. 1980, 19, 3225.

Ni(II) Macrocycle Complexes
Inorganic Chemistry, Vol. 37, No. 19, 1998 4811
Table 2. Crystallographic Data for [Ni(L)(CH3CN)2](ClO4)2 (1), [Ni(Lox)2](ClO4)2 (2), [Ni(NCS)2(L)] (4), and [Ni(L)(py)2](ClO4)2 (5)
1
2
4
5
empirical formula
fw
T,°C
C21H26Cl2N3NiO8PS2
673.15
21
C34H40Cl2N2O10P2S4
956.47
21
C19H20N3NiPS4
508.30
20
C27H30Cl2N3NiO8PS2
749.25
23
λ, Å
0.710 69
12.704(2)
13.538(2)
17.377(2)
90.0
107.554(8)
90.0
0.710 69
10.564(1)
11.975(2)
9.124(2)
109.79(1)
95.67(2)
109.19(1)
996.6(3)
1
0.710 69
11.139(2)
13.270(2)
14.885(1)
90.0
92.34(1)
90.0
0.710 69
13.063(2)
16.615(3)
14.973(3)
90.0
91.76(2)
90.0
a, Å
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
2849.4(7)
4
2198.5(5)
4
3248(1)
4
space group
P21/c (No. 14)
1.569
1.12
P1h (No. 2)
P21/n (No. 14)
1.536
1.35
P21/c (No. 14)
1.532
0.99
F
calcd, g cm-3
1.594
µ, mm-1
F(000)
transm coeff
Ra
0.97
494
1384
1048
1544
0.90-1.00
0.88-1.11
0.85-1.00
0.80-1.00
0.070
0.059
0.028
0.046
Rw
0.076b
0.067b
0.059c
0.049b
2
2
2
a R ) ∑||Fo| - |Fc||/∑|Fo|. b Rw ) [∑w(|Fo| - |Fc|)2/∑w|Fo| ]1/2
.
c Rw ) [∑[w(F0 - Fc2)2]/∑[w(F0 )2]]1/2
.
Electronic Spectroscopy. The electronic spectra of the Ni-
(II) complexes in acetonitrile solution are consistent with their
pseudooctahedral symmetry. The spectra show two d-d bands
(ν1 and ν2), whereas the third or highest energy band expected
for octahedral Ni(II) complexes (3A2 f 3T1(P), ν3) is overlapped
with a strong charge-transfer band starting around 400 nm,
which in the case of 7 and 8 shifts to lower energies and partially
overlaps the ν2 absorption. The spectral data and the ligand
field parameter, ∆o, for all the compounds except 5 (see above)
are given in Table 1. Complex 1 has the largest value of ∆o
(12 077 cm-1) in this series. This value is clearly superior to
those reported for the octahedral tetrathiomacrocyclic Ni(II)
Conclusions
The macrocycle L behaves as a four-coordinate ligand toward
Ni(II), leaving free two adjacent coordination sites on the
hexacoordinated metal ion in a relative cis orientation, which
are filled by anionic ligands (chloride, thiocyanate) or solvent
molecules (acetonitrile), depending on the Ni(II) salt used. The
reactions described here show that the solvent molecules in the
[Ni(L)(CH3CN)2]2+ complex cation could be easily replaced by
different ligands, but maintaining the macrocycle L coordinated
to the Ni(II) atom. All of this confirms the key role of the
complex 1 in this work and evidences their potential usefulness
as starting products in reactions to obtain new Ni(II) macrocyclic
complexes.
complexes18 [Ni([n]aneS4)(CH3CN)2]2+ {10 810-10 290 cm-1
[n]aneS4 [12]aneS4 (1,4,7,10-tetrathiacyclododecane),
;
)
[14]aneS4 (1,4,8,11-tetrathiacyclotetradecane), and [16]aneS4
(1,5,9,13-tetrathiacyclohexadecane)}, where the relative disposi-
tion of the acetonitrile molecules (cis or trans) is uncertain, and
closer to that observed in the complex [Ni(L1)(CH3CN)2]2+
[11 800 cm-1, L1 ) 1,6-bis(2-pyridyl)-2,5-dithiahexane], which
contains an N2S2 open-chain ligand.10 Complexes 3, 4, and 6-8
show ∆o values ranging from 10 977 to 10 638 cm-1. All these
complexes contain the same (L)Ni(II) coordinated subunit so,
the differences between their ∆o values are due to the additional
monodentate or N-chelating ligands in the complex. This is
confirmed when the values of ∆o are ordered giving the
sequence 7 (o-phen) > 8 (bipy) > 6 (en) > 4 (SCN) > 3 (Cl),
which fits well with the classical spectrochemical series.19 The
N2S2O2 environment of the Ni(II) atom in 2 makes this complex
different than the other Ni(II) complexes reported here. This
is evidenced by the ∆o value (11 848 cm-1), which is more like
those reported for other NxS3-x or NxO3-x (x ) 1,2-bismacro-
cyclic Ni(II) complexes such as [Ni([9]aneNS2)2]2+ (11 930
cm-1, [9]aneNS2 ) 1,4-dithia-7-azacyclononane),20 [Ni([9]-
aneN2S)2]2+ (11 770 cm-1, [9]aneN2S ) 1-thia-4,7-diazacy-
clononane),21 or [Ni([9]aneN2O)2]2+ (11 600 cm-1, [9]aneN2O
) 1-oxa-4,7-diazacyclononane).21
Experimental Procedures
General Methods. Reagent grade solvents were purified by
distillation before use. Commercial grade chemicals were used without
purification. The ligand 6-phenyl-15-aza-6-phospha-3,9-dithiabicyclo-
[9,3,1]pentadeca-1(15),11,13-triene (L) was obtained by a described
procedure.3 Elemental analyses were performed by the Service of
Chemical Analysis of the Universitat Auto`noma de Barcelona using a
Carlo Erba EA-1108 instrument. Electronic and IR spectra were
recorded using Kontron-Uvicon 860 and Perkin-Elmer FT-1710 instru-
ments, respectively.
Safety Note. Perchlorate salts of metal complexes with organic
ligands are potentially explosiVe. Only small amounts of material
should be prepared, and these should be handled with great caution.
Synthesis of the Ni(II) Complexes. [Ni(L)(CH3CN)2](ClO4)2 (1).
Ni(ClO4)2‚6H2O (0.219 g, 0.598 mmol) dissolved in acetonitrile (3 cm3)
was added to a solution of L (0.200 g, 0.599 mmol) in dichloromethane
(2 cm3). The violet mixture was stirred for 1 h in air, and then diethyl
ether (2 cm3) was added. The resulting solution was kept at -5 °C
overnight. A violet crystalline precipitate (1) was formed which was
filtered off and vacuum-dried. Yield: 0.310 g (77%). Anal. Found:
C, 37.0; H, 3.7; N, 5.9; S, 9.6. Calcd for C21H26Cl2N3NiO8PS2: C,
37.47; H, 3.89; N, 6.24; S, 9.53.
[Ni(Lox)2](ClO4)2 (2). Preparation from L. Ni(ClO4)2‚6H2O
(0.109 g, 0.299 mmol) dissolved in acetone (2 cm3) was added to a
solution of L (0.200 g, 0.599 mmol) in acetonitrile (3 cm3). The green
mixture was stirred for 1 h in air, and then diethyl ether (2 cm3) was
added. The resulting solution was stirred for 5 min, and a green
precipitate (2) was formed, which was filtered off and vacuum-dried.
Yield: 0.220 g (82%).
Preparation from 1. A solution of L (0.025 g, 0.074 mmol) in
dichloromethane (2 cm3) was slowly added to a solution of 1 (0.050 g,
0.074 mmol) in acetonitrile (3 cm3). The violet mixture was stirred
(18) Blake, A. J.; Halcrow, M. A.; Schro¨der, M. J. Chem. Soc., Dalton
Trans. 1992, 2803.
(19) Jørgensen, C. K. Absortion Spectra and Chemical Bonding in
Complexes; Pergamon Press: Oxford, 1962; Chapter 7.
(20) (a) McAuley, A.; Subramanian, S. Inorg. Chem. 1990, 29, 2830. (b)
Chandrasekhar, S.; McAuley, A. Inorg. Chem. 1992, 31, 480.
(21) (a) Fabbrizzi, L.; Proserpio, D. M. J. Chem. Soc., Dalton Trans. 1989,
229. (b) Hart, S. M.; Boeyens, J. C. A.; Hancock, R. D. Inorg. Chem.
1983, 22, 989.

4812 Inorganic Chemistry, Vol. 37, No. 19, 1998
Table 3. Selected Bond Lengths (Å) and Angles (deg) for 1
Escriche et al.
Table 5. Selected Bond Lengths (Å) and Angles (deg) for 4
Ni(1)-S(1)
Ni(1)-S(2)
Ni(1)-P(1)
Ni(1)-N(1)
Ni(1)-N(2)
Ni(1)-N(3)
S(1)-C(1)
S(1)-C(11)
S(2)-C(7)
S(2)-C(8)
P(1)-C(9)
2.442(3)
2.442(3)
2.342(2)
2.082(6)
2.090(7)
2.023(7)
1.797(9)
1.817(9)
1.811(9)
1.817(9)
1.822(8)
P(1)-C(10)
P(1)-C(12)
N(1)-C(2)
N(1)-C(6)
N(2)-C(18)
N(3)-C(20)
C(1)-C(2)
C(6)-C(7)
C(8)-C(9)
C(10)-C(11)
1.82(1)
1.834(8)
1.35(1)
1.347(9)
1.11(1)
1.12(1)
1.51(1)
1.47(1)
1.53(1)
1.55(1)
Ni(1)-N(1)
Ni(1)-N(2)
Ni(1)-N(3)
Ni(1)-P(1)
Ni(1)-S(1)
Ni(1)-S(2)
S(1)-C(1)
S(1)-C(11)
2.108(2)
2.067(2)
2.026(2)
2.3669(7)
2.4566(8)
2.4784(8)
1.810(3)
1.822(3)
S(2)-C(7)
S(2)-C(8)
S(3)-C(18)
S(4)-C(19)
P(1)-C(10)
P(1)-C(9)
N(2)-C(18)
N(3)-C(19)
1.797(3)
1.819(3)
1.627(3)
1.626(3)
1.829(3)
1.830(3)
1.156(3)
1.161(3)
N(3)-Ni(1)-N(2)
N(3)-Ni(1)-N(1) 169.60(8) N(1)-Ni(1)-S(2)
88.84(9) N(2)-Ni(1)-S(2)
103.79(7)
82.39(6)
84.21(3)
161.33(3)
102.0(2)
100.9(2)
108.8(2)
N(2)-Ni(1)-N(1)
N(3)-Ni(1)-P(1)
N(2)-Ni(1)-P(1)
N(1)-Ni(1)-P(1)
N(3)-Ni(1)-S(1)
N(2)-Ni(1)-S(1)
N(1)-Ni(1)-S(1)
P(1)-Ni(1)-S(1)
N(3)-Ni(1)-S(2)
84.16(8) P(1)-Ni(1)-S(2)
97.52(7) S(1)-Ni(1)-S(2)
169.67(7) C(1)-S(1)-C(11)
90.54(6) C(7)-S(2)-C(8)
103.46(7) C(10)-P(1)-C(9)
S(1)-Ni(1)-S(2)
S(1)-Ni(1)-P(1)
S(1)-Ni(1)-N(1)
S(2)-Ni(1)-P(1)
S(2)-Ni(1)-N(1)
P(1)-Ni(1)-N(1)
P(1)-Ni(1)-N(2)
N(1)-Ni(1)-N(3)
N(2)-Ni(1)-N(3)
C(1)-S(1)-C(11)
163.61(9)
84.91(8)
84.2(2)
85.50(8)
83.0(2)
C(7)-S(2)-C(8)
C(9)-P(1)-C(10)
Ni(1)-N(2)-C(18)
Ni(1)-N(3)-C(20)
S(1)-C(1)-C(2)
S(2)-C(7)-C(6)
S(2)-C(8)-C(9)
P(1)-C(9)-C(8)
P(1)-C(10)-C(11)
S(1)-C(11)-C(10)
101.6(4)
109.4(4)
174.2(6)
172.7(9)
116.4(7)
116.5(5)
115.3(7)
109.5(6)
107.9(6)
113.5(5)
87.35(7) C(18)-N(2)-Ni(1) 149.5(2)
83.93(6) C(19)-N(3)-Ni(1) 151.1(2)
92.4(2)
178.0(2)
172.5(3)
85.8(3)
83.27(3) C(8)-C(9)-P(1)
108.8(2)
91.86(7) C(11)-C(10)-P(1) 108.7(2)
Table 6. Selected Bond Lengths (Å) and Angles (deg) for 5
100.6(4)
Ni(1)-S(1)
Ni(1)-S(2)
Ni(1)-P(1)
Ni(1)-N(1)
Ni(1)-N(2)
Ni(1)-N(3)
S(1)-C(1)
S(1)-C(11)
S(2)-C(7)
S(2)-C(8)
2.515(2)
2.468(2)
2.343(2)
2.123(5)
2.115(5)
2.100(5)
1.799(7)
1.822(7)
1.793(7)
1.821(6)
P(1)-C(9)
P(1)-C(10)
P(1)-C(12)
N(1)-C(2)
N(1)-C(6)
C(1)-C(2)
C(6)-C(7)
C(8)-C(9)
C(10)-C(11)
1.822(6)
1.819(6)
1.816(6)
1.349(7)
1.352(8)
1.511(9)
1.506(9)
1.526(8)
1.529(9)
Table 4. Selected Bond Lengths (Å) and Angles (deg) for 2
Ni(1)-S(1)
Ni(1)-O(1)
Ni(1)-N(1)
S(1)-C(1)
S(1)-C(11)
S(2)-C(7)
S(2)-C(8)
P(1)-O(1)
P(1)-C(9)
2.451(2)
2.022(3)
2.189(6)
1.799(7)
1.819(7)
1.827(7)
1.814(8)
1.515(5)
1.809(7)
P(1)-C(10)
P(1)-C(12)
N(1)-C(2)
N(1)-C(6)
C(1)-C(2)
C(6)-C(7)
C(8)-C(9)
C(10)-C(11)
1.799(9)
1.789(7)
1.34(1)
1.35(1)
1.51(1)
1.50(1)
1.51(1)
1.53(1)
S(1)-Ni(1)-S(2)
S(1)-Ni(1)-P(1)
S(1)-Ni(1)-N(1)
S(2)-Ni(1)-P(1)
S(2)-Ni(1)-N(1)
P(1)-Ni(1)-N(1)
P(1)-Ni(1)-N(2)
N(1)-Ni(1)-N(3)
N(2)-Ni(1)-N(3)
C(1)-S(1)-C(11)
159.91(6)
83.74(6)
81.4(1)
84.43(6)
82.9(1)
C(7)-S(2)-C(8)
C(9)-P(1)-C(10)
C(9)-P(1)-C(12)
C(10)-P(1)-C(12)
S(1)-C(1)-C(2)
S(2)-C(7)-C(6)
S(2)-C(8)-C(9)
P(1)-C(9)-C(8)
P(1)-C(10)-C(11)
S(1)-C(11)-C(10)
102.4(3)
108.0(3)
108.4(3)
107.3(3)
116.1(4)
115.6(4)
116.0(4)
110.6(4)
110.6(4)
115.5(4)
S(1)-Ni(1)-O(1)
S(1)-Ni(1)-N(1)
O(1)-Ni(1)-N(1)
Ni(1)-S(1)-C(1)
Ni(1)-S(1)-C(11)
C(1)-S(1)-C(11)
C(7)-S(2)-C(8)
O(1)-P(1)-C(9)
O(1)-P(1)-C(10)
O(1)-P(1)-C(12)
92.8(2)
79.8(2)
91.5(2)
C(9)-P(1)-C(10)
C(9)-P(1)-C(12)
C(10)-P(1)-C(12)
Ni(1)-O(1)-P(1)
S(1)-C(1)-C(2)
S(2)-C(7)-C(6)
S(2)-C(8)-C(9)
P(1)-C(9)-C(8)
P(1)-C(10)-C(11)
S(1)-C(11)-C(10)
109.5(4)
107.4(3)
105.1(4)
133.8(3)
114.7(5)
108.2(6)
115.4(7)
116.1(4)
114.3(6)
118.2(6)
90.9(3)
113.5(3)
103.5(4)
102.0(4)
111.0(4)
112.8(3)
110.9(3)
92.1(1)
177.6(2)
176.6(2)
86.8(2)
99.7(3)
stirred for 5 min. A blue precipitate (4) was formed, which was filtered
off and vacuum-dried. Yield: 0.029 g (66%). Anal. Found: C, 44.6;
H, 3.8; N, 8.1; S, 25.0. Calcd for C19H20N3NiPS4: C, 44.97; H, 3.98;
N, 8.29; S, 25.23.
for 2 h in air. During this time the solution changes from violet to
green. The resulting solution was treated with diethyl ether (2 cm3)
and stirred for 5 min. A green precipitate (2) was formed, which was
filtered off and vacuum-dried. Yield: 0.058 g (82%). Anal. Found:
C, 42.5; H, 4.2; N, 2.8; S, 13.2. Calcd for C34H40Cl2N2NiO10P2S4: C,
42.69; H, 4.21; N, 2.93; S, 13.41.
[Ni(L)(py)2](ClO4)2 (5). Pyridine (6 mg, 0.074 mmol) was slowly
added to a solution of 1 (25 mg, 0.037 mmol) in acetone (3 cm3). The
violet mixture was stirred for 2 h in air. During this time the solution
changed from violet to green. The resulting solution was treated with
diethyl ether (2 cm3) and stirred for 5 min. A green precipitate (5)
was formed, which was filtered off and vacuum-dried. Yield: 0.023
g (82%). Anal. Found: C, 43.3; H, 4.1; N, 5.4; S, 8.5. Calcd for
C27H30Cl2N3NiO8PS2: C, 43.37; H, 4.05; N, 5.62; S, 8.56.
[NiCl2(L)] (3). Preparation from L. NiCl2‚6H2O (0.071 g, 0.300
mmol) dissolved in acetonitrile (2 cm3) was added to a solution of L
(0.100 g, 0.300 mmol) in acetonitrile (2 cm3). The resulting solution
was stirred for 15 min in air, and a green precipitate (3) was formed,
which was filtered off and vacuum-dried. Yield: 0.108 g (77%).
Preparation from 1. Me4NCl (8 mg, 0.068 mmol) was slowly
added to a solution of 1 (23 mg, 0.034 mmol) in acetonitrile (3 cm3).
The resulting solution was stirred in air for half an hour, and a green
precipitate (3) was formed, which was filtered off and vacuum-dried.
Yield: 0.012 g (76%). Anal. Found: C, 43.9; H, 4.3; N, 2.9; S, 13.5.
Calcd for C17H20Cl2NNiPS2: C, 44.09; H, 4.35; N, 3.02; S, 13.85.
[Ni(NCS)2(L)] (4). Preparation from L. Ni(SCN)2‚H2O (0.073
g, 0.410 mmol) dissolved in acetonitrile (2 cm3) was added to a solution
of L (0.127 g, 0.381 mmol) in dichloromethane (2 cm3). The resulting
solution was stirred for half an hour in air, and a blue precipitate (4)
was formed which was filtered off and vacuum-dried. Yield: 0.120 g
(62%).
[Ni(L)(en)](ClO4)2 (6). Ethylenediamine (3.1 mg, 0.051 mmol) was
slowly added to a solution of 1 (35 mg, 0.051 mmol) in acetone (2
cm3). The green mixture was stirred for 15 min in air. The resulting
solution was treated with diethyl ether (2 cm3) and cooled at 4 °C for
10 h. A green precipitate (6) was formed, which was filtered off and
vacuum-dried. Yield: 0.031 g (93%). Anal. Found: C, 35.0; H, 4.2;
N, 6.1; S, 9.2. Calcd for C19H22Cl2N3NiO8PS2: C, 35.13; H, 4.35; N,
6.47; S, 9.85.
[Ni(L)(o-phen)](ClO4)2 (7). o-Phenanthroline (8.9 mg, 0.044 mmol)
was slowly added to a solution of 1 (31 mg, 0.044 mmol) in acetone
(3 cm3). The resulting solution was stirred for 15 min in air, and a
pink precipitate (7) formed, which was filtered off and vacuum-dried.
Yield: 0.028 g (82%). Anal. Found: C, 44.9; H, 3.5; N, 5.3; S, 8.1.
Calcd for C29H28Cl2N3NiO8PS2: C, 45.25; H, 3.67; N, 5.46; S, 8.32.
Preparation from 1. KSCN (17 mg, 0.172 mmol) was slowly added
to a solution of 1 (58 mg, 0.086 mmol) in acetonitrile (3 cm3). The
resulting solution was stirred for half an hour in air, and a white
precipitate (KClO4) appeared, which was filtered off and discarded.
The remaining solution was treated with diethyl ether (10 cm3) and
[Ni(L)(bipy)](ClO4)2 (8). 2,2′-Bipyridine (4.7 mg, 0.030 mmol) was
slowly added to a solution of 1 (20 mg, 0.030 mmol) in acetone (3

Ni(II) Macrocycle Complexes
Inorganic Chemistry, Vol. 37, No. 19, 1998 4813
cm3). The resulting solution was stirred for 15 min in air, and a dark
yellow precipitate (8) formed, which was filtered off and vacuum-dried.
Yield: 0.013 g (59%). Anal. Found: C, 43.3; H, 3.6; N, 5.6; S, 8.4.
Calcd for C27H28Cl2N3NiO8PS2: C, 43.49; H, 3.79; N, 5.64; S, 8.58.
X-ray Data Collections and Structure Determinations of 1, 2, 4,
and 5. Single-crystal data collections for 1, 2, 4, and 5 were performed
at ambient temperature with a Rigaku AFC5S diffractometer using
monochromatized Mo KR radiation (λ ) 0.710 69 Å) and ω-2θ scan
mode. The unit cell parameters were determined by least-squares
refinements of 25 carefully centered reflections. Each set of data was
corrected for Lorentz and polarization effects and for absorption (ψ
scans). A total of 5251, 3508, 4297, and 5934 unique reflections were
collected (2θmax ) 50°) for 1, 2, 4, and 5, respectively, and of those
3087, 2658, 3089, and 3020 were considered as observed. The three
check reflections monitored after every 150 reflections showed no decay
during the course of data collections.
refined with anisotropic displacement parameters. The methyl group
containing C(19) was refined as a rigid group with a group isotropic
displacement parameter, but the hydrogen atoms connected to C(21)
could not be positioned. The rest of the hydrogen atoms were placed
at their calculated positions [C-H ) 0.95 Å and U(H) ) 1.2Ueq(host
atom)].
For 2 and 5, all non-hydrogen atoms were refined with anisotropic
displacement parameters and hydrogen atoms were placed at their
calculated positions. For 4, non-hydrogen atoms were refined with
anisotropic and hydrogen atoms with fixed isotropic displacement
parameters.
Neutral atomic scattering factors were those included in the programs.
Crystallographic data are presented in Table 2, and selected bond
parameters for complexes 1, 2, 4, and 5 are in Tables 3, 4, 5, and 6,
respectively.
Acknowledgment. We acknowledge with thanks the finan-
cial assistance of Comisio´n Interministerial de Ciencia y
Tecnolog´ıa (CICYT) of the Spanish Government provided by
the project MAT97-0720. R.K. thanks the Ministerio de
Educacio´n y Ciencia of Spanish Government for Grant SAB95-
0249 and the Oskar O¨ flunds Foundation for financial support.
The structures were solved by direct methods using SHELXS86.22
Least-squares refinements were performed using the crystallographic
software packages of XTAL23 for 1 and 2, SHELXL-9324 for 4, and
TEXSAN25 for 5. The structures of 1, 2, and 5 were refined on F, and
that of 4, on F2.
In complex 1, one of the perchlorate ions exhibits rotational disorder.
The two forms of the ion have the oxygen O(5) in common and they
differ by rotation around Cl(2)-O(5) bond. The non-hydrogen atoms,
except the disordered oxygen atoms and the methyl carbon C(19), were
Supporting Information Available: X-ray crystallographic files,
in CIF format, for the structure determinations of 1, 2, 4, and 5 are
available on the Internet only. Access information is given on any
current masthead page.
(22) Sheldrick, G. M. SHELXS-86. Program for Crystal Structure Solution.
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(23) Hall, S. R., Flack, H. D., Stewart, J. M., Eds. XTAL3.2 User’s Guide;
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(24) Sheldrick, G. M. SHELXL-93: Program for Crystal Structure Refine-
ment; University of Go¨ttingen: Germany, 1993.
IC9714753
(25) TEXSAN-TEXRAY: Single-Crystal Structure Analysis Software, Ver-
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