ISSN 0036 0236, Russian Journal of Inorganic Chemistry, 2011, Vol. 56, No. ...... F. A. Cotton and G. B. Wilkinson, Advanced Inorganic. Chemistry, 5th ed. (Wiley ...
ISSN 00360236, Russian Journal of Inorganic Chemistry, 2011, Vol. 56, No. 2, pp. 223–231. © Pleiades Publishing, Ltd., 2011. Original Russian Text © D.V. Chachkov, O.V. Mikhailov, 2011, published in Zhurnal Neorganicheskoi Khimii, 2011, Vol. 56, No. 2, pp. 261–269.
THEORETICAL INORGANIC CHEMISTRY
Calculation of Geometric Parameters of Macrocyclic Metal Chelates Formed by Template Synthesis in Tertiary Systems M(II) Ion–Ethanedithioamide–Formaldehyde–Ammonia D. V. Chachkov and O. V. Mikhailov Supercomputer Center, Kazan Scientific Center, Russian Academy of Sciences, Kazan, Tatarstan, Russia Kazan State Technological University, ul. K. Marksa 68, Kazan, Tatarstan, 420015 Russia Received November 24, 2009
Abstract—The geometric parameters of macrotricyclic Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes with 2,8dithio3,5,7triazanonanedithioamide1,9 with the (N,N,S,S) coordination of the chelant donor centers (formed by template synthesis in the M(II)–ethanedithioamide–formaldehyde– ammonia system) have been calculated by the hybrid B3LYP density functional theory method with the use of the 631G(d) basis set and the Gaussian 98 program package. The bond lengths and bond angles in the complexes with the MN2S2 coordination core have been reported. Calculations demonstrated that in none of the complexes are the fivemembered chelate rings planar and that these rings in the Zn(II) complex are sig nificantly different. For all M(II) ions under consideration, an additional sixmembered chelate ring result ing from template crosslinking is turned at a rather large angle to the two fivemembered rings and this ring itself is nonplanar. DOI: 10.1134/S0036023611020057
Previously [1, 2], it has been experimentally shown that, in the tertiary Ni(II)–ethanedithioamide H2N– C(=S)–C(=S)–NH2)–formaldehyde–ammonia and Cu(II)–ethanedithioamide–formaldehyde–ammonia systems, template synthesis occurs in the nickel(II) or copper(II) hexacyanoferrate(II) gelatinimmobilized matrix (GIM). EPR and magnetic susceptibility data have shed some light on the coordination of the ligand (socalled chelant) formed in the course of synthesis to the Ni(II) and Cu(II) ions. However, the question concerning the 3D structure of the resultant metal complexes remains open since crystals suitable for Xray crystallography have not been obtained so far using available methods of their isolation from the reaction system. Therefore, it is expedient to perform quantumchemical calculations of these metal com plexes by a modern ab initio method, which permits obtaining independent information on their geometric parameters. In addition, it is of interest to perform analogous calculations for Mn(II), Fe(II), Co(II), and Zn(II) complexes of the same composition, which can form in the course of template synthesis in corre sponding metal(II) hexacyanoferrate(II) GIMs. In this paper, we report and discuss the results of quan tumchemical calculations by the threeparameter hybrid B3LYP density functional theory (DFT) method.
COMPUTATIONAL DETAILS Quantumchemical calculations were performed by the hybrid B3LYP DFT method with the common 631G(d) basis set, which is a combination of the Har tree–Fock and DFT methods [3]. Calculations were performed with the Gaussian 98 program package [4]. Each core AO of the basis set was described by six Gaussiantype orbitals (GTOs), the valence sАО was described by three GTOs, the valence рАО was described by one GTO augmented with a polarization d GTO for each р function. The correspondence of stationary points to energy minima was proved in all cases by Hessian calculations (all positive eigenval ues). Preliminary approbation of the method for dif ferent 3dmetal chelate complexes showed that the former predicted with sufficient reliability basic geo metric parameters of their structures (Cartesian coor dinates of all atoms, bond lengths, bond angles, dihe dral angles). All quantumchemical calculations were performed at the Supercomputer Center, Kazan Sci entific Center, Russian Academy of Sciences. RESULTS AND DISCUSSION According to experimental evidence [1, 2], the template process that occurs in the tertiary Ni(II)– ethanedithioamide–formaldehyde–ammonia and Cu(II)–ethanedithioamide–formaldehyde–ammonia systems in Ni2[Fe(CN)6] and Cu2[Fe(CN)6] GIMs,
223
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CHACHKOV, MIKHAILOV (а)
(b) H
H
H
H
N
H
H C
C
H H C N
H
N
H
N
N
H N
C
C S
Mn
S
S
S
S
S
S
C
C
H
C
H
N
H
Fig. 1. 3D structure of the template Mn(II) complex with 2,8dithio3,5,7triazanonanedithioamide1,9. Here and in Figs. 2– 6, (a) is the front view, (b) is the side view.
(а) H
(b) H
H
N H
C
H
H
N
N C
H
C
N Fe
N
H
N
S
C
H
H C
H
H
C
S
H N N
H
C
H S
C
H S S
S S
S
Fig. 2. 3D structure of the template Fe(II) complex with 2,8dithio3,5,7triazanonanedithioamide1,9.
respectively, is described by the following general scheme (M = Ni, Ci):
ing scheme for the complexes under consideration is shown below (M is a metal atom).
O
S S
HN
M
2
+ 2NH3
N1
S
NH
HN
S
S
NH +
[Fe(CN)6]4–
C
NH
S
S
6
(1)
Available experimental data allow us to assume that analogous template reactions occur in other M(II)– ethanedithioamide–formaldehyde–ammonia sys tems (M = Mn, Fe, Co, Zn) when complexation is carried out in corresponding M2[Fe(CN)6] GIMs. These processes lead to the formation of macrotricyclic complexes of the above 3dmetal ions with the tetraden tate chelant 2,8dithio3,5,7triazanonanedithioam ide1,9, which is coordinated to the M(II) ion through two nitrogen and two sulfur atoms. The atom number
2
C
S4
C
M13
3
N11
S12
N
9
C8
N7
5
H
H15 H21
+ 8H2O.
H17
H14
M2[Fe(CN)6] + 4H2N–C–C–NH2 + 4HCH + 4OH–
C H
18
20
C N24
16
S10
19
H
23
H22
H25
Each complex contains three chelate rings: two fivemembered rings and one sixmembered ring appeared as a result of template crosslinking. The (N,N,S,S) coordination of 2,8dithio3,5,7triaza nonanedithioamide1,9 to the metal atoms is on the whole consistent with the Pearson HSAB principle [5, 6]. The structures of the complexes with similar coordi nation predicted by calculations are shown in Figs. 1– 6, and bond lengths and bond angles are summarized in Tables 1–6.
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225
(b)
H
H
H
N
H
H C
H C
H H N
N
H
H
C
C
H N
H Co
S
H
N
N
N
C
S
N
C
H
S
C
S
S
S
S
Fig. 3. 3D structure of the template Co(II) complex with 2,8dithio3,5,7triazanonanedithioamide1,9.
(а)
(b) H
H
H
N
H
H
H C H
H H
C
C
N H S N
N
C
H
H S
N
N
C
H
C
Ni S
N
S N
C
Ni
C S
C
H S
H
S
C
Fig. 4. 3D structure of the template Ni(II) complex with 2,8dithio3,5,7triazanonanedithioamide1,9.
noting that, in nearly all complexes, the tetragon formed by the donor atoms (NSSN) is planar (the sum of its interior angles is indistinguishable from 360°). The only exception is the Zn(II) complex where this sum is 346.6°. The MN2S2 chelate cores can also be treated as planar since the M atoms are only slightly out of the (NSSN) plane (the sum of the bond angles S(4)M(13)S(12), S(12)M(13)N(7), N(7)M(13)N(5), and N(5)M(13)S(4) in the metal chelate group is 353.8° (Mn), 356.4° (Fe), 354.9° (Co), 358.4° (Ni), and 353.0°
As follows from the data obtained, all macrotricy clic metal complexes have coplanar orientation of the donor centers around the central ion. The spin multi plicity of the ground state (2S + 1) is 6 (Mn), 5 (Fe), 4 (Co), 3 (Ni), 2 (Cu), and 1 (Zn). The difference in energy between the structures with a spin multiplicity other than the ground state multiplicity (quartet for Mn(II), triplet for Fe(II), doublet for Co(II), singlet for Ni(II), quarter for Cu(II), and triplet for Zn(II)) and the corresponding ground state is 90.0, 17.6, 16.2, 23.4, 122.6, and 117.4 kJ/mol, respectively. It is worth (а)
(b) H
H N H
H
H
H
C
H
C
C
H N N H
S
C
H
N
C
N
N
H
C C
Cu S
S
S
Cu S
N
C
H
C
H
Fig. 5. 3D structure of the template Cu(II) complex with 2,8dithio3,5,7triazanonanedithioamide1,9. RUSSIAN JOURNAL OF INORGANIC CHEMISTRY
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CHACHKOV, MIKHAILOV (а)
(б) H
H
H H H
H S
N
N
S
H C
H
H C
C C
C
N
H
N
H
C N
H H
N
H N C
S
C
H
H S C
Zn S
Zn N
C
C
S
N H
S
Fig. 6. 3D structure of the template Zn(II) complex with 2,8dithio3,5,7triazanonanedithioamide1,9.
(Zn); hence, their difference from 360° is no more than 7°). The average M–N and M–S bond lengths in these complexes are 238.5 and 237.9 pm in the Mn(II) com plex, 226.8 and 232.4 pm for Fe(II), 220.1 and 227.7 pm for Co(II), 194.3 and 219.3 pm for Ni(II), and 206.8
and 227.0 pm for Cu(II). The like bonds are of nearly the same length: for example, the Fe–N bond lengths are 226.7 and 226.8 pm and the Fe–S bond lengths are 232.4 and 232.4 pm. The M–N bonds in all com plexes, except the Mn complex, are shorter than the M–S bonds. The difference between these bonds
Table 1. Calculated geometric parameters of the Mn(II) complex structure Bond angles, ω, deg
Bond lengths, d, pm 1, 2 1, 14 2, 3 2, 4 3, 5 3, 6 4, 13 5, 13 5, 15 5, 18 7, 8 7, 13 7, 16 7, 19 8, 9 8, 10 9, 11 9, 12 11, 17 12, 13 18, 20 18, 21 18, 24 19, 22 19, 23 19, 24 24, 25
127.3 102.5 150.3 179.2 142.0 163.6 237.9 238.5 102.2 152.7 142.0 238.6 102.2 152.7 150.3 163.6 127.3 179.2 102.5 237.9 109.4 109.4 142.9 109.4 109.4 142.9 101.4
2, 1, 14 1, 2, 3 1, 2, 4 3, 2, 4 2, 3, 5 2, 3, 6 5, 3, 6 2, 4, 13 3, 5, 13 3, 5, 15 3, 5, 18 13, 5, 15 13, 5, 18 15, 5, 18 8, 7, 13 8, 7, 16 8, 7, 19 13, 7, 16 13, 7, 19 16, 7, 19 7, 8, 9 7, 8, 10 9, 8, 10 8, 9, 11
110.3 118.6 128.1 113.3 113.7 124.5 121.7 100.2 104.8 107.5 117.2 117.5 101.4 108.7 104.7 107.5 117.3 117.5 101.4 108.8 113.7 121.7 124.5 118.5
8, 9, 12 11, 9, 12 9, 11, 17 9, 12, 13 4, 13, 5 4, 13, 12 5, 13, 7 7, 13, 12 5, 18, 20 5, 18, 21 5, 18, 24 20, 18, 21 20, 18, 24 21, 18, 24 7, 19, 22 7, 19, 23 7, 19, 24 22, 19, 23 22, 19, 24 23, 19, 24 18, 24, 19 18, 24, 25 19, 24, 25
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113.4 128.1 110.3 100.3 82.2 114.1 75.4 82.1 108.9 107.2 112.6 108.3 109.1 110.6 107.2 108.9 112.6 108.3 110.6 109.1 120.8 114.5 114.5
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Table 2. Calculated geometric parameters of the Fe(II) complex structure Bond angles, ω, deg
Bond lengths, d, pm 1, 2
127.3
2, 1, 14
110.4
8, 9, 12
112.9
1, 14
102.5
1, 2, 3
118.9
11, 9, 12
128.3
2, 3
150.1
1, 2, 4
128.4
9, 11, 17
110.4
2, 4
179.1
3, 2, 4
112.8
9, 12, 13
99.5
3, 5
143.0
2, 3, 5
113.3
4, 13, 5
84.5
3, 6
163.2
2, 3, 6
124.9
4, 13, 12
108.9
4, 13
232.4
5, 3, 6
121.6
5, 13, 7
78.6
5, 13
226.7
2, 4, 13
99.3
7, 13, 12
84.4
5, 15
102.2
3, 5, 13
107.3
5, 18, 20
108.6
5, 18
153.2
3, 5, 15
106.9
5, 18, 21
107.2
7, 8
142.9
3, 5, 18
115.8
5, 18, 24
112.3
7, 13
226.8
13, 5, 15
117.0
20, 18, 21
108.7
7, 16
102.2
13, 5, 18
102.3
20, 18, 24
109.0
7, 19
153.2
15, 5, 18
107.9
21, 18, 24
110.9
8, 9
150.1
8, 7, 13
107.2
7, 19, 22
107.2
8, 10
163.3
8, 7, 16
106.9
7, 19, 23
108.6
9, 11
127.4
8, 7, 19
115.9
7, 19, 24
112.4
9, 12
179.0
13, 7, 16
117.0
22, 19, 23
108.7
11, 17
102.5
13, 7, 19
102.3
22, 19, 24
110.8
12, 13
232.4
16, 7, 19
108.0
23, 19, 24
109.0
18, 20
109.4
7, 8, 9
113.4
18, 24, 19
120.8
18, 21
109.3
7, 8, 10
121.6
18, 24, 25
114.2
18, 24
142.9
9, 8, 10
124.9
19, 24, 25
114.2
19, 22
109.3
8, 9, 11
118.8
19, 23
109.4
19, 24
142.9
24, 25
101.4
increases in the series Mn–Fe–Co–Ni and somewhat decreases in going from Ni to Zn. The M–N and M– S bond lengths monotonically decrease in the series Mn–Fe–Co–Ni and slightly increase in going from Ni to Zn (Tables 1–6). In this context, the sharp difference in the Z–N bond lengths (d(5, 13) = 217.9 pm; d(7, 13) = 354.1 pm) is noteworthy. The second value is so large (more than 300 pm) that this even brings the question about the existence of the metal–nitrogen chemical bond. It is worth noting that the Zn–S distance (d(10, 13), 256.9 pm) is considerably shorter that the zinc–nitrogen distance. RUSSIAN JOURNAL OF INORGANIC CHEMISTRY
This allows us to suggest that the chemical bond is pre cisely between these atoms rather than between the metal nitrogen atoms, as in the other complexes under consideration. However, once the third zinc–sulfur bond has actually formed, the complex should contain a severely distorted eightmembered ring, which is hardly probable (although not ruled out in principle). The sum of the MSC, SCC, CCN, CNM, and NMS bond angles in each of the two fivemembered chelate rings is 514.2° (Mn), 517.2° (Fe), 520.5° (Co), 525.5° (Ni), and 522.5° (Cu). In all cases, this sum is smaller than the sum of the interior angles in a planar Vol. 56
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Table 3. Calculated geometric parameters of the Co(II) complex structure Bond angles, ω, deg
Bond lengths, d, pm 1, 2
127.5
2, 1, 14
110.2
8, 9, 12
113.7
1, 14
102.5
1, 2, 3
118.3
11, 9, 12
127.9
2, 3
150.1
1, 2, 4
128.0
9, 11, 17
110.2
2, 4
178.7
3, 2, 4
113.7
9, 12, 13
99.7
3, 5
142.9
2, 3, 5
113.6
4, 13, 5
85.6
3, 6
163.3
2, 3, 6
125.0
4, 13, 12
101.9
4, 13
227.7
5, 3, 6
121.6
5, 13, 7
81.8
5, 13
220.0
2, 4, 13
99.7
7, 13, 12
85.6
5, 15
102.2
3, 5, 13
107.9
5, 18, 20
108.6
5, 18
153.3
3, 5, 15
107.0
5, 18, 21
107.1
7, 8
142.9
3, 5, 18
116.3
5, 18, 24
112.3
7, 13
220.1
13, 5, 15
116.8
20, 18, 21
108.9
7, 16
102.2
13, 5, 18
101.7
20, 18, 24
109.0
7, 19
153.2
15, 5, 18
107.6
21, 18, 24
110.9
8, 9
150.1
8, 7, 13
107.8
7, 19, 22
107.1
8, 10
163.3
8, 7, 16
107.0
7, 19, 23
108.6
9, 11
127.5
8, 7, 19
116.3
7, 19, 24
112.3
9, 12
178.7
13, 7, 16
116.8
22, 19, 23
108.9
11, 17
102.5
13, 7, 19
101.7
22, 19, 24
110.9
12, 13
227.7
16, 7, 19
107.6
23, 19, 24
109.0
18, 20
109.4
7, 8, 9
113.6
18, 24, 19
120.9
18, 21
109.2
7, 8, 10
121.2
18, 24, 25
114.2
18, 24
142.9
9, 8, 10
125.0
19, 24, 25
114.2
19, 22
109.2
8, 9, 11
118.3
19, 23
109.4
19, 24
142.9
24, 25
101.4
pentagon (540.0°); thus, these rings are nonplanar (although their deviation from a flat structure is small). In the Zn(II) complex, the distortion of these rings is more significant; in addition, these rings are not iden tical (the bond angle sum is 511.7° in one ring and 444.2° in the other ring). It is quite natural that the car bon–carbon, carbon–sulfur, and carbon–nitrogen bonds in the chelate rings are also rather different (for example, in the Mn(II) complex, these distances are 150.3, 179.2, and 142.0 pm, respectively; in the Cu(II) complex, they are 149.8, 177.9, and 143.5 pm, respec
tively). However, these bond lengths depend relatively weakly on the M(II) nature. The extra sixmembered ring formed through tem plate crosslinking is not located in the same plane with the MN2S2 chelate core; in all cases, this ring is tilted at a considerable angle to the chelate core: 70.2° for Mn, 69.7° for Fe, 69.3° for Co, 70.0° for Ni, and 70.4° for Cu. The magnitudes of the C(18)N(5)M(13)N(7) and C(19)N(7)M(13)N(5) torsion angles, which can serve as a quantitative char acteristic of this tilt, are almost the same in all the complexes. The sixmembered ring itself is also non
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Table 4. Calculated geometric parameters of the Ni(II) complex structure Bond angles, ω, deg
Bond lengths, d, pm 1, 2
127.7
2, 1, 14
110.4
8, 9, 12
111.8
1, 14
102.5
1, 2, 3
119.1
11, 9, 12
129.0
2, 3
149.2
1, 2, 4
129.0
9, 11, 17
110.4
2, 4
177.4
3, 2, 4
111.8
9, 12, 13
99.0
3, 5
144.9
2, 3, 5
112.4
4, 13, 5
89.0
3, 6
162.8
2, 3, 6
126.7
4, 13, 12
91.0
4, 13
219.3
5, 3, 6
120.8
5, 13, 7
89.4
5, 13
194.3
2, 4, 13
99.0
7, 13, 12
89.0
5, 15
102.4
3, 5, 13
113.3
5, 18, 20
108.5
5, 18
153.9
3, 5, 15
105.4
5, 18, 21
106.8
7, 8
144.9
3, 5, 18
114.0
5, 18, 24
111.8
7, 13
194.3
13, 5, 15
115.3
20, 18, 21
109.4
7, 16
102.4
13, 5, 18
102.7
20, 18, 24
109.1
7, 19
153.8
15, 5, 18
106.2
21, 18, 24
111.2
8, 9
149.2
8, 7, 13
113.3
7, 19, 22
106.8
8, 10
162.8
8, 7, 16
105.4
7, 19, 23
108.5
9, 11
127.7
8, 7, 19
114.0
7, 19, 24
111.9
9, 12
177.4
13, 7, 16
115.3
22, 19, 23
109.4
11, 17
102.5
13, 7, 19
102.6
22, 19, 24
111.2
12, 13
219.3
16, 7, 19
106.2
23, 19, 24
109.1
18, 20
109.4
7, 8, 9
112.4
18, 24, 19
119.8
18, 21
109.1
7, 8, 10
120.8
18, 24, 25
113.6
18, 24
143.0
9, 8, 10
126.7
19, 24, 25
113.6
19, 22
109.1
8, 9, 11
119.1
19, 23
109.4
19, 24
143.0
24, 25
101.4
planar: the nitrogen atom in it is out of the N–CH2– CH2–N plane by an angle of 65.0° (Mn), 63.5° (Fe), 63.8° (Co), 59.2° (Ni), or 62.6° (Cu). The C(19)N(24)C(18)N(5) and C(18)N(24)C(13)N(7) torsion angles, which characterize the degree of this distortion, are also close to each other in all metal complexes under consideration. At the background of these complexes, the zinc(II) complex is an exception: the above pairs of torsion angles are considerably dif ferent (72.2° and 57.5° and 73.3° and 62.3°, respec tively). RUSSIAN JOURNAL OF INORGANIC CHEMISTRY
Two aspects are of interest. First, our calculation demonstrates that the Ni(II) complex with the ligand has the triplet ground state and, hence, must be para magnetic. This conclusion, however, contradicts the information in [1] that the complex is diamagnetic and is colored brown (which is precisely typical of planar Ni(II) complexes [7]). It is likely that B3LYP calcula tions with the use of a more extended basis set than 631G(d) is required to elucidate the reasons for this inconsistency. Vol. 56
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Table 5. Calculated geometric parameters of the Cu(II) complex structure Bond angles, ω, deg
Bond lengths, d, pm 1, 2
127.7
2, 1, 14
110.3
8, 9, 12
113.1
1, 14
102.5
1, 2, 3
118.4
11, 9, 12
128.5
2, 3
149.8
1, 2, 4
128.5
9, 11, 17
110.3
2, 4
177.9
3, 2, 4
113.1
9, 12, 13
98.3
3, 5
143.5
2, 3, 5
113.2
4, 13, 5
87.3
3, 6
163.1
2, 3, 6
125.7
4, 13, 12
96.2
4, 13
227.0
5, 3, 6
121.0
5, 13, 7
86.5
5, 13
206.9
2, 4, 13
98.3
7, 13, 12
87.3
5, 15
102.3
3, 5, 13
110.6
5, 18, 20
108.6
5, 18
153.2
3, 5, 15
106.6
5, 18, 21
106.9
7, 8
143.4
3, 5, 18
115.5
5, 18, 24
112.2
7, 13
206.8
13, 5, 15
116.4
20, 18, 21
108.9
7, 16
102.2
13, 5, 18
100.4
20, 18, 24
109.1
7, 19
153.2
15, 5, 18
107.6
21, 18, 24
110.9
8, 9
149.9
8, 7, 13
110.5
7, 19, 22
106.9
8, 10
163.1
8, 7, 16
106.6
7, 19, 23
108.6
9, 11
127.7
8, 7, 19
115.5
7, 19, 24
112.3
9, 12
177.9
13, 7, 16
116.4
22, 19, 23
109.0
11, 17
102.5
13, 7, 19
100.4
22, 19, 24
110.9
12, 13
227.0
16, 7, 19
107.6
23, 19, 24
109.1
18, 20
109.3
7, 8, 9
113.2
18, 24, 19
120.3
18, 21
109.2
7, 8, 10
121.0
18, 24, 25
114.2
18, 24
142.9
9, 8, 10
125.7
19, 24, 25
114.2
19, 22
109.2
8, 9, 11
118.4
19, 23
109.3
19, 24
142.9
24, 25
101.4
Second, the Zn(II) complex is structurally rather different from the other complexes. At least, this com plex has no symmetry elements, whereas the other complexes have symmetry plane. The reasons for this difference are still unclear but can be outlined. As already mentioned, the Zn–N bond lengths in this complex are sharply different (the difference exceeds 100 pm), which can be evidence that the (N,S,S,N) coordination of 2,8dithio3,5,7triazanonanedithio amide1,9 donor sites to Zn(II) is energetically unfa vorable. Indeed, our calculation of the zinc(II) com plex with 2,8dithio3,5,7triazanonanedithioamide 1,9 and the (N,N,N,N) coordination of ligand donor sites shows that this structure is 39.2 kJ/mol more
favorable than the structure with the (N,S,S,N) coor dination. At the same time, Zn(II) is known to be a rather hard acid according to the Pearson classifica tion (the orbital electronegativity in the gas phase is 15.82 eV [5]); therefore, coordination through hard donor sites of the ligand (through nitrogen atoms in our case) should be more typical of zinc(II) resulting in the ZnN4 or ZnN3S rather than ZnN2S2 chelate core. Thus, it is quite probable that the Zn(II) complex with 2,8dithio3,5,7triazanonanedithioamide1,9 and the N2S2 (or NS3) coordination mode of the ligand to the zinc ion have a rather stressed and asymmetric structure, which is supported by our computation results. However, further studies are required to con
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CALCULATION OF GEOMETRIC PARAMETERS
231
Table 6. Calculated geometric parameters of the Zn(II) complex structure Bond angles, ω, deg
Bond lengths, d, pm 1, 2 1, 14 2, 3 2, 4 3, 5 3, 6 4, 13 5, 13 5, 15 5, 18 7, 8 7, 13 7, 16 7, 19 8, 9 8, 10 9, 11 9, 12 11, 17 12, 13 18, 20 18, 21 18, 24 19, 22 19, 23 19, 24 24, 25
127.2 102.5 150.3 179.7 143.8 163.2 226.5 217.2 102.0 155.4 133.2 354.1 101.8 149.0 151.6 170.5 127.9 176.6 102.6 229.5 109.2 109.2 142.9 108.9 109.2 144.2 101.4
2, 1, 14 1, 2, 3 1, 2, 4 3, 2, 4 2, 3, 5 2, 3, 6 5, 3, 6 2, 4, 13 3, 5, 13 3, 5, 15 3, 5, 18 13, 5, 15 13, 5, 18 15, 5, 18 8, 7, 13 8, 7, 16 8, 7, 19 13, 7, 16 13, 7, 19 16, 7, 19 7, 8, 9 7, 8, 10 9, 8, 10 8, 9, 11
firm this assumption. It is worth noting that, by the dipole moment calculated by the B3LYP method, the zinc complex (6.64 D) does not stand out against the background of the other complexes (6.12, 6.56, 6.66, 6.72, and 6.86 D for the Mn, Fe, Co, Ni, and Cu com plexes, respectively). ACKNOWLEDGMENTS This work was supported by the Russian Founda tion for Basic Research (project no. 090397001).
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110.5 119.1 128.8 112.0 113.5 124.3 122.0 91.0 103.3 106.1 114.9 111.5 114.4 106.4 42.2 114.6 125.4 105.1 103.9 115.6 117.1 121.3 121.6 114.8
8, 9, 12 11, 9, 12 9, 11, 17 9, 12, 13 4, 13, 5 4, 13, 12 5, 13, 7 7, 13, 12 5, 18, 20 5, 18, 21 5, 18, 24 20, 18, 21 20, 18, 24 21, 18, 24 7, 19, 22 7, 19, 23 7, 19, 24 22, 19, 23 22, 19, 24 23, 19, 24 18, 24, 19 18, 24, 25 19, 24, 25
115.7 129.5 110.4 93.0 92.0 125.8 58.9 76.7 107.4 107.5 113.2 109.5 109.3 109.8 107.0 108.1 113.2 108.7 111.0 108.7 121.3 114.0 114.7
REFERENCES 1. O. V. Mikhailov, Heterocyclic Commun. 7 (1), 79 (2001). 2. O. V. Mikhailov, Asian Chem. Lett. 12 (4), 258 (2008). 3. A. D. Becke, J. Chem. Phys. 98 (7), 1372 (1993). 4. M. J. Frisch, G. W. Trucks, H. B. Schlegel, et al., Gaus sian 98, Gaussian, Inc., Pittsburg, 1998. 5. Yu. N. Kukushkin, Coordination Chemistry (Vysshaya Shkola, Moscow, 1985) [in Russian]. 6. R. J. Pearson, J. Am. Chem. Soc. 85 (22), 3533 (1963). 7. F. A. Cotton and G. B. Wilkinson, Advanced Inorganic Chemistry, 5th ed. (Wiley, New York, 1990).
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