Reaction of chlorine with platinum(IV) triamine containing N,N-dimethylethylenediamine. the crystal structure of [Pt{(CH3) 2N(CH2)2NH2}PyCl3] Cl·H2O[Pt{(CH3)2N(CH2) 2NCl}PyCl3], and [Pt{(CH3)2N(CH 2)2NH2...

Article abstract of DOI:10.1134/S0036023608120061

Full title: Reaction of chlorine with platinum(IV) triamine containing N,N-dimethylethylenediamine. the crystal structure of [Pt{(CH₃) ₂N(CH₂)₂NH₂}PyCl₃] Cl·H₂O[Pt{(CH₃)₂N(CH₂) ₂NCl}PyCl₃], and [Pt{(CH₃)₂N(CH ₂)₂NH₂}PyCl₄]. The Platinum(II) diamine with N,N-dimethylethylenediamine (N,N-dimeEn) [Pt{(CH₃)₂N(CH₂)₂NH ₂}Cl₂] (I) was synthesized. The reaction of the diamine with pyridine gave Pt(II) tetramine [Pt{(CH₃)₂N(CH ₂)₂NH₂}Py₂]Cl₂ (II), which was oxidized with chlorine to give Pt(IV) triamine Pt{[(CH ₃)₂N(CH₂)₂}PyCl₃]Cl ? H₂O (III). The reaction of III with chlorine (chloroamidation) yielded chloroimide [Pt{(CH₃)₂N(CH₂) ₂NCl}PyCl₃] (IV). The IR spectra of complexes I-IV and UV/Vis spectra of III and IV were studied. X-Ray diffraction analysis was performed for III (monoclinic crystals, space group P2₁/c, a = 7.7437(6), b = 8.1100(7), c = 28.52992(2) A?, β = 93.7280(10)°, Z = 4, R _hkl = 0.0420) and IV (orthorhombic crystals, space group Pna2₁, a = 15.7825(12), b = 7.4447(6), c = 12.3099(6) A?, Z = 4, R _hkl = 0.0539). During oxidation of Pt(II) tetramine with chlorine, the pyridine molecule is removed from the cis position relative to the (CH ₃)₂N group (trans position relative to the NH₂ group) of N,N-dimethylethylenediamine. The reaction of chloroimide complex IV with concentrated HCl (dechloroamidation) at 20°C afforded the initial complex III; that at 100°C, gave triamine III together with Pt(IV) diamine [Pt(N,N-dimeEn)Cl₄] (V) (monoclinic crystals, space group P2 ₁/n, a = 7.1278(5), b = 11.5384(8), c = 12.7501(9) A?, β = 93.23(10)°, Z = 4, R _hkl = 0.0239).

Full text of DOI:10.1134/S0036023608120061

ISSN 0036-0236, Russian Journal of Inorganic Chemistry, 2008, Vol. 53, No. 12, pp. 1862–1869. © Pleiades Publishing, Ltd., 2008.
Original Russian Text © T.N. Fedotova, G.G. Aleksandrov, G.N. Kuznetsova, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 12, pp. 1992–1999.
COORDINATION
COMPOUNDS
Reaction of Chlorine with Platinum(IV) Triamine Containing
N,N- Dimethylethylenediamine.
The Crystal Structure of[Pt{(CH ) N(CH ) NH }PyCl ]Cl ·
3
2
2 2
2
3
H O[Pt{(CH ) N(CH ) NCl}PyCl ], and [Pt{(CH ) N(CH ) NH }PyCl ]
2
3 2
2 2
3
3 2
2 2
2
4
T. N. Fedotova, G. G. Aleksandrov, and G. N. Kuznetsova
Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences,
Leninskii pr. 31, Moscow, 119991 Russia
Received May 5, 2008
Abstract—The
Platinum(II)
diamine
with
N,N-dimethylethylenediamine
(N,N-dimeEn)
[
Pt{(CH ) N(CH ) NH }Cl ] (I) was synthesized. The reaction of the diamine with pyridine gave Pt(II) tetra-
3
2
2 2
2
2
mine [Pt{(CH ) N(CH ) NH }Py ]Cl (II), which was oxidized with chlorine to give Pt(IV) triamine
3
2
2 2
2
2
2
Pt{[(CH ) N(CH ) }PyCl ]Cl · H O (III). The reaction of III with chlorine (chloroamidation) yielded chlor-
3
2
2 2
3
2
oimide [Pt{(CH ) N(CH ) NCl}PyCl ] (IV). The IR spectra of complexes I–IV and UV/Vis spectra of III and
3
2
2 2
3
IV were studied. X-Ray diffraction analysis was performed for III (monoclinic crystals, space group P2 /c,
1
a = 7.7437(6), b = 8.1100(7), c = 28.52992(2) Å, β = 93.7280(10)°, Z = 4, Rhkl = 0.0420) and IV (orthorhombic
crystals, space group Pna2 , a = 15.7825(12), b = 7.4447(6), c = 12.3099(6) Å, Z = 4, R = 0.0539). During
1
hkl
oxidation of Pt(II) tetramine with chlorine, the pyridine molecule is removed from the cis position relative to
the (CH ) N group (trans position relative to the NH group) of N,N-dimethylethylenediamine. The reaction of
3
2
2
chloroimide complex IV with concentrated HCl (dechloroamidation) at 20°C afforded the initial complex III;
that at 100°C, gave triamine III together with Pt(IV) diamine [Pt(N,N-dimeEn)Cl ] (V) (monoclinic crystals,
4
space group P2 /n, a = 7.1278(5), b = 11.5384(8), c = 12.7501(9) Å, β = 93.23(10)°, Z = 4, R = 0.0239).
1
hkl
DOI: 10.1134/S0036023608120061
The 195Pt and N NMR studies of the reactions of [Pt(NH
14
CH
CH
NCl)PyCl
] or (in another publication
2
2
2
3
mixed platinum(IV) amine complexes containing both [8]) orange complex [Pt(NH CH CH NHCl)PyCl ]Cl.
2
2
2
3
ethylenediamine and ammonia molecules with chlorine In our experiment, red chloroimide was formed during
have shown that only ammonia molecules are involved the first 2–5 min of chlorination of this triamine, while
in the reaction [1]. Aliphatic ring-forming diamines, in after ~10–15 min a lighter compound started to appear,
particular, ethylenediamine, propylenediamine, trime- and subsequently a dark yellow complex was produced.
thylenediamine (En, Pn, Tn), being incorporated in plat- We were unable to separate sufficient amounts of these
inum(IV) triamines and tetramines are involved into complexes by consecutive filtration and recrystalliza-
reactions with chlorine only in those cases where the tion; therefore, we studied chloroamidation for Pt(IV)
complexes contain aromatic amine ligands with π-accep- complexes with one reactive NH group in a ring-form-
2
tor properties (Py, bipy) [2–7]. The inner-sphere En and ing diamine and attempted to obtain the product of
Pn, which form five-membered metal rings with plati- reaction of this Pt(IV) complex with chlorine in a high
num, are converted into N- and N,N'-chloroimides in yield and study it by X-ray diffraction. No structural
these reactions. In these aliphatic diamines, both NH2 data for chloroamidation products of platinum com-
groups are equivalent and equally reactive. Therefore, plexes containing a chelating diamine were available so
the reactions with chlorine give several products difficult far. Only the crystal structure of the product of chloro-
to identify rather than a single complex. In Pt(IV) tri- amidation
of
2 2
Pt(IV)
ammonia
complex
amines, the NH group located in the trans-position to an [Pt(NH ) (NCl ) Cl]Cl is known [9]. In this work, we pre-
2
3 3
anionic ligand was found to be most reactive. However, pared platinum(II) diamine with N,N-dimethylethylenedi-
chlorination of triamines, too, gave a mixture of several amine (N,N-dimeEn), made this compound to react with
compounds rather than one complex. For example, the pyridine to obtain platinum(II) tetramine, and carried out
reaction of Pt(IV) triamine [PtEn PyCl ]Cl with chlorine oxidation with chlorine, which gave platinum(IV) tri-
3
was reported [3] to yield a bright-red chloroimide amine [{Pt[CH ) N(CH ) NH ]PyCl }Cl · H O instead
3 2 2 2 2 3 2
1
862

REACTION OF CHLORINE WITH PLATINUM(IV) TRIAMINE CONTAINING
1863
–1
of Pt(IV) tetramine. The reaction of the obtained product
with chlorine afforded chloroimide derivative of Pt(IV) ν(éç); 3210 w ν(NH); 1630 s δ(ç é); 1581 m δ(NH )
The IR spectrum of complex II (cm ): 3438 s, 3358 s
2
2
triamine,
namely
[Pt{(CH ) N(CH ) NCl}PyCl ].
–1
3
2
2 2
3
and narrow strong bands at 1611, 770, and 699 cm cor-
responding to pyridine ring vibrations.
Dechloroamidation at 20°C and at 100°ë was also studied.
Synthesis of [Pt{(CH ) N(CH ) NH }PyCl ]Cl ·
3
2
2 2
2
3
H O (III). Chlorine was slowly passed for 10 min
2
EXPERIMENTAL
through a solution of freshly prepared platinum(II) tet-
ramine (0.45 g) in water (3 mL) containing several
drops of HCl (1 : 1) (to prevent the formation of chlo-
roamides). The solution turned yellow and a solid
started to precipitate almost immediately. After 1 h, the
precipitate was collected on a filter and, without any
Synthesis of [Pt{(CH ) N(CH ) NH }Cl ] (I).
3
2
2 2
2
2
K PtCl (5 g) was dissolved in boiling water (15 ml).
2
4
After cooling with magnetic stirring, N,N-dimethyleth-
2
0
ylenediamine (d = 0.803) (1.5 ml, 10% excess) was
added to the suspension. K PtCl gradually dissolved,
2
4
and a pale precipitate started to form. After 1 h, the washing, kept in a dessicator over fused KOH for 48 h
gray-yellow precipitate was filtered off and, as precipi- to give 0.31 g of finely crystalline pale yellow powder
tation progressed, the product was collected several (~67%).
more times on the same filter. The product was recrys-
For C H Cl N OPt anal. calcd. (%): Pt, 37.36; N,
9
19
4
3
tallized from hot water containing some HCl (~10%
solution). This gave finely crystalline (needles) light
green-colored compound, fraction 1, 0.7 g (~16.5%).
8
.04; C, 20.75; H, 3.60; Cl, 27.10; H O, 3.44.
2
Found (%): Pt, 37.58; N, 7.46; C, 22.31; H, 2.86; Cl,
After separation of fraction 1, a mixture of yellow- 25.31; H
O, 3.42.
2
green and red (probably [Pt(N,N-dimeEn) ][PtCl ])
–1
2
4
The IR spectrum of III exhibits bands (cm ): 3450 m,
compounds was isolated from the filtrate. This mixture
was not separated by two recrystallizations. The filtrate
obtained after the second recrystallization (together
with wash water) was concentrated on a rotary evapo-
rator and combined with the mixture. The complex
~
3129 w, 1630 vw, and 1572 m assigned to ν(OH),
ν(NH), δ(H O), and δ(NH ), respectively, and narrow
2
2
–
1
strong bands at 1602, 761, and 687 cm caused by pyri-
dine ring vibrations.
Recrystallization from water gave crystals of III
suitable for X-ray diffraction.
[
Pt(NH ) ]Cl (0.6 g) was added, and the mixture was
3 4 2
heated with continuous stirring. After 15 min, green
Magnus salt [Pt(NH ) ][PtCl ] precipitated from the
3
4
4
The IR spectrum of the crystals of III was identical
hot green solution and was collected on a filter. Light to the spectrum of non-recrystallized sample except for
–
1
green finely crystalline Pt(II) diamine gradually precip- stronger δ(H O) band (1630 cm ), which is due to
2
itated from the filtrate. The product was washed with
dilute HCl (~10%) and ethanol to give fraction 2, 1.43 g.
The overall yield was 2.13 g (~50%).
higher content of crystallization water after recrystalli-
zation (three H O molecules instead of one molecule
2
according to X-ray diffraction data).
For C H Cl N Pt anal. calcd. (%): Pt, 55.08.
4
12
2
2
Synthesis of [Pt{(CH ) N(CH ) NCl}PyCl ] (IV).
3
2
2 2
3
Found (%): Pt, 54.79 (fraction 1).
Found (%): Pt, 54.91 (fraction 2).
Chlorine was slowly passed for 5–7 min through a solu-
tion of complex I (0.136 g) in water (5 mL). A bright
orange solid started to precipitate almost immediately.
After 30 min, the red precipitate was collected on a fil-
ter; at the end of filtration, several drops of water were
added to the precipitate. The filtrate was yellowish. The
precipitate was kept in air for 1 h and then in a dessica-
tor over fused KOH for 24 h to give 0.122 g (~89.5%)
of finely crystalline homogeneous (under a micro-
Synthesis of [Pt{(CH ) N(CH ) NH }Py ]Cl · H O
3
2
2 2
2
2
2
2
(
II). A mixture of diamine I, pyridine (0.2 mL), and
water (10 mL) was heated on a water bath until the
diamine dissolved (~1 h). After cooling, the colorless
solution was filtered, evaporated almost to dryness, and
left overnight in a vacuum dessicator over P O to give
2
5
0
~
.5 g of a snow-white finely crystalline tetramine II in scope) dark cherry-colored compound insoluble in
85% yield.
For C H Cl N OPt ([Pt(N,N-dimeEn)Py )]Cl · H O)
water.
For C H Cl N Pt anal. calcd. (%): Pt, 38.85; C,
14
24
2
4
2
2
2
9
15
4
3
anal. calcd. (%): Pt, 36.79; Cl, 13.37; N, 10.56;
C, 31.70.
2
1.53; N, 8.36; H, 3.01; Cl , 28.24; Clouter, 0.0.
tot
Found (%): Pt, 38.40; C, 22.01; N, 8.07; H, 2.67;
Found (%): Pt, 37.92; Cl, 13.71; 13.65.
Cl , 28.55; Clouter, 0.0.
tot
After storage in a dessicator for 5 days, found (%):
Pt, 39.16; N, 9.95; 9.89; C, 28.16; 28.63.
Found (%): Pt, 38.56; C, 22.18; N, 8.08; H, 2.60;
tot
Cl , 28.33; Clouter, 0.0
After 1.5 months, found (%): Pt, 43.45; Cl, 15.60;
N, 9.27; 9.01; C, 24.01; 24.49.
The compound is readily soluble in acetonitrile and
dimethylformamide (DMF) to form bright red solutions
For C H Cl N OPt ([Pt(N,N-dimeEn)PyCl)]Cl · H O) from which bright red crystals suitable for X-ray dif-
9
19
2
3
2
anal. calcd. (%): Pt, 43.23; Cl, 15.71; N, 9.31; C, 23.96. fraction were obtained.
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 12 2008

1
864
FEDOTOVA et al.
The IR spectrum of complex IV contains no ν(NH)
or ν(NH ) bands; the strong bands at 1602, 768, and
2
–1
C1
C3
N1
6
91 cm due to pyridine ring vibrations are retained;
–
1
Cl2
the band at 662 cm becomes much more intense than
in the initial complex I and may probably be assigned
to ν(N−Cl).
C2
C4
C9
C8
Pt(1)
C7
Reaction of complex IV with concentrated HCl
dechloroamidation). Concentrated HCl (2 ml) was
N2
(
N3
C5
added to complex IV (25 mg). The bright red color dis-
appeared immediately but the yellow complex was not
completely dissolved. After addition of hot water
C6
Cl1
Cl3
(1 ml), the solution was filtered and left to evaporate in
air. This gave pale yellow crystals, which were studied
by X-ray diffraction (complex VI).
+
Fig. 1. Complex [Pt{(CH ) N(CH ) NH }PyCl ] in com-
3
2
2 2
2
3
pound III.
A mixture of complex IV (25 mg) and concentrated
HCl (3 mL) was heated on a boiling water bath; this
was accompanied by vigorous evolution of bubbles an
chlorine smell. After 15 min, the precipitate dissolved
and during slow cooling on the hot switched-off bath,
very fine crystals separated from the solution. The solu-
tion was concentrated almost to dryness to give a mix-
ture of very thin pale yellow plate crystals and a number
of yellow crystals of a different habit. This mixture was
recrystallized from hot water with addition of HCl.
This gave two kinds of crystals, which were studied by
X-ray diffraction (complexes VII and V).
Cl2
C2
C1
Cl3
C3
N1
C9
Pt(1)
C8
C4
C5
N2
–1
IR absorption spectra in the 4000–400 cm range
were recorded on a Specord M-82 spectrophotometer
for mineral oil mulls.
Cl1
N3
C6
C7
UV/Vis spectra of an aqueous solution of III and a
Cl4
DMF solution of IV were recorded on a Varian/Cary
5
0 spectrophotometer.
X-Ray diffraction. The experimental data for struc-
ture solution for III, IV, and V were collected from
Fig. 2. Complex [Pt{(CH ) N(CH ) NCl}PyCl ] in com-
pound IV.
3
2
2 2
3
0
.33 × 0.23 × 0.15, 0.45 × 0.24 × 0.03, and 0.32 × 0.18 ×
.09 mm single crystals, respectively, using Bruker
0
Smart CCD Apex II automated diffractometer (293 K,
λMoK , λ 0.71073 Å, graphite monochromator, ω scan
α
mode). The absorption correction was applied semiem-
pirically. The structures of III, IV, and VII were solved
by the direct method and refined by the least-squares
method using SHELXS-97 [10] and SHELXL-97 [11]
software in the anisotropic full-matrix approximation
for non-hydrogen atoms. The positions of H atoms
were calculated geometrically and refined isotropically
in the riding model.
The key crystal data and X-ray experiment details
for compounds III– V are summarized in Table 1, atom
coordinates and thermal factors are in Table 2, and
interatomic distances and bond angles are in Table 3.
Cl3
C1
N1
Cl1
Pt(1)
C4
N2
C3
Cl4
C2
Cl2
RESULTS AND DISCUSSION
For investigating chloroamidation of platinum(IV)
complexes containing an aliphatic diamine with one
reactive NH group, Pt(II) diamine I was prepared by
Fig. 3. Complex [Pt{(CH ) N(CH ) NH }Cl ] in com-
pound V.
2
3
2
2 2
2
4
the reaction of K PtCl with N,N-dimethylethylenedi-
2
4
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 12 2008

REACTION OF CHLORINE WITH PLATINUM(IV) TRIAMINE CONTAINING
1865
Table 1. Crystal data and X-ray experiment details for III, IV, and V
III
C H C N O Pt
IV
V
Formula weight
Molecular formula
System
C H C N Pt
C H C N Pt
9
23 l4
3
3
9
15 l4
3
4
12 l4
2
558.19
502.13
425.05
Monoclinic
Orthorhombic
Pna21
Monoclinic
Space group
a, Å
P2 /c
P2 /n
1
1
7.7437(6)
8.1100(7)
15.7825(12)
7.4447(6)
12.3099(10)
90
7.1278(5)
11.5384(8)
12.7501(9)
93.2300(10)
1046.95(13)
4
b, Å
c, Å
28.529(2)
93.7280(10)
1787.9(3)
4
β, deg
V, Å3
1446.4(2)
4
Z
ρcalcd, g/cm3
µ, cm–1
2.074
2.306
2.697
8.454
10.422
14.367
F(000)
1072
944
784
θ, deg
3.30–30.34
2.58–31.49
2.38–31.74
Index range
–10 < h < 10, –11 < k < 11, –23 < h < 18, –10 < k < 10, –9 < h < 10, –16 < k < 15,
–
22 < l < 39
–17 < l < 17
–18 < l < 18
The total number of measured reflec-
tions
9910
13720
9682
The number of independent reflections 4841 [R(int) = 0.0463]
4589 [R(int) = 0.0387]
3320 [R(int) = 0.0280]
The number of refined parameters
207
143
100
GOOF on F2
R [I > 2σ(I)]
1.002
1.013
1.002
R1 = 0.0420, wR2 = 0.0943 R1 = 0.0539, wR2 = 0.1361 R1 = 0.0239, wR2 = 0.0484
R (for all reflections)
R1 = 0.0514, wR2 = 0.0974 R1 = 0.1123, wR2 = 0.1896 R1 = 0.0381, wR2 = 0.0536
∆
ρmax and ∆ρmin e/Å
2.463 and –2.408
2.711 and –1.698
1.387 and –0.754
amine. Dissolution of the resulting platinum diamine in [Pt{(CH ) N(CH ) NH }PyCl ]Cl · 3H O (Fig. 1).
3
2
2 2
2
3
2
a small excess of pyridine (1 : 5) with heating followed Thus, upon chlorine oxidation of the tetramine [Pt(N,N-
by evaporation yielded a snow-white finely crystalline dimeEn)Py ]Cl , one pyridine molecule is replaced by
2
2
powder. According to elemental analysis, the complex
was Pt(II) tetramine (II). Analysis of this sample after
–
Cl . However, as noted above, this platinum(II) tetra-
mine loses a Py molecule also during long-term stor-
age, being converted spontaneously into Pt(II) triamine.
5
days showed higher contents of Pt and Cl and lower
contents of C and N. One month later, the compound
corresponded, according to elemental analysis, to plat-
It is noteworthy that the tetramine [PtEnPy ]Cl does
not lose pyridine even on long-term storage or on chlo-
rination of Pt(IV) tetramine [PtEnPy Cl ]Cl [4]. This
2
2
inum(II) triamine [Pt(N,N-dimeEn)PyCl]Cl · H O (see
2
Experimental).
2
2
2
Chlorine oxidation of an aqueous solution of the difference in the behaviors of platinum tetramines with
freshly prepared Pt(II) tetramine II at room temperature En and N,N-dimeEn is due to the presence of two CH
3
afforded a light yellow complex, which was identified groups at one nitrogen atom of ethylenediamine, result-
as platinum(IV) triamine III according to elemental ing in specific steric features that dictate the chemical
analysis.
The UV/Vis spectrum of a solution of III exhibited
the following bands in the visible region: 410 nm
behavior of the complex.As a consequence, triamine III
is formed instead of platinum(IV) tetramine.
The addition of several drops of HCl (1 : 1) to the
reaction solution (to prevent the chloroimide forma-
tion) accelerates the removal of the pyridine molecule
–
1
(
24390 cm , ε = 51.8 L/(mol cm)) and 352 nm
–
1
(
28410 cm , ε = 216.5 L/(mol cm)). The positions and
intensities of these bands corresponded to Pt(IV) tri-
–
with replacement by Cl . Chlorine oxidation of plati-
–
1
amines (compare 25000 cm and ε = 55.8 L/(mol cm)
for [PtEnPyCl ]Cl).
num(II) tetramine without addition of HCl yielded an
orange-colored mixture, recrystallization of which
3
X-Ray diffraction data supported the assumption from warm water gave a yellow compound and insolu-
that complex III is Pt(IV) triamine, ble bright red finely crystalline chloroimide precipitate.
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 12 2008

1
866
FEDOTOVA et al.
4
Table 2. Atom coordinates (×10 ) and equivalent isotropic According to X-ray diffraction data, the yellow product
3
thermal factors (×10 ) for III, IV, V (U is 1/3 of the sum of
eq
was triamine III.
orthogonalized anisotropic Uij)
The reaction of an aqueous solution of complex III
with chlorine gave a bright red-colored, water-insolu-
ble, finely crystalline homogeneous compound.
According to elemental analysis, this was the expected
chloroimide [Pt{(CH ) N(CH ) NCl}PyCl ] (IV) (Fig. 2).
2
Atom
x
y
z
U , Å
eq
III
Pt(1)
–3033(1) –2698(1)
–464(2) –1260(2)
–5438(2) –4383(2)
–3848(2) –1869(2)
1492(2) –3309(2)
–2448(7) –3303(6)
935(1)
930(1)
947(1)
25(1)
38(1)
39(1)
40(1)
52(1)
32(1)
31(1)
30(1)
52(2)
49(2)
49(2)
52(2)
38(1)
43(2)
42(2)
42(2)
37(1)
79(2)
69(2)
91(2)
3
2
2 2
3
Cl(1)
Cl(2)
Cl(3)
Cl(4)
N(1)
N(2)
N(3)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
O(1W)
O(2W)
O(3W)
The IR spectrum of complex IV contained no ν(OH),
ν(NH), δ(H O), or δ(NH )absorption bands observed in the
2
2
176(1)
IR spectrum of initial complex III (see Experimental). The
visible region of the UV/Vis spectrum of a DMF solution of
2109(1)
1624(2)
1216(2)
690(2)
1917(3)
1724(2)
1160(3)
1006(3)
314(2)
138(2)
362(3)
754(2)
909(2)
–1
IV exhibited absorption bands at 447 nm (22370 cm ,
–4287(6)
–632(5)
–1
ε = 762.7 L/(mol cm)), 394 nm (25380 cm , ε =
–1742(6) –4712(5)
–3589(12) –2286(8)
–3702(10) –609(8)
–6224(8)
–3806(9)
–2371(8) –5545(7)
–1536(9) –6871(8)
–6(9) –7405(7)
633(8) –6559(7)
–248(8) –5223(7)
6661(10) 3602(8)
–1
1
627 L/(mol cm)), 345 nm (28985 cm ,
ε
=
1
822 L/(mol cm)), their intensity being much higher
than that of the d−d absorption bands in the spectrum of
initial triamine III. These spectral changes are always
observed in chloroamidation of Pt(IV) amine com-
plexes and are due to the presence of complexes with
–735(8)
985(7)
–
2
–
chloroimide groups R–NCl and NCl in the solution
[4].
As noted above, we carried out the reaction of tri-
amine [PtEnPyCl ]Cl with chlorine several times and
1963(3)
1830(3)
2075(3)
3
obtained three compounds of different colors (red, yel-
low, and dark yellow) depending on the chlorination time
and solution concentration. The compositions of these
complexes and the initial triamine are the same according
to elemental analysis (Pt : Cl : C : N = 1 : 4 : 9 : 3). Red
chloroimide is always contaminated by some yellow
compound. The intensity of UV/Vis absorption bands
3108(9)
884(11)
3129(9)
693(9)
IV
Pt(1)
Cl(1)
Cl(2)
Cl(3)
Cl(4)
N(2)
N(3)
N(1)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
1056(1)
8443(1)
5000
54(1)
1796(6) 10055(13) 6351(9)
1770(7) 10093(14) 3655(11)
153(6)
–407(7)
1975(8)
123(5)
148(6)
94(3)
105(3)
96(7)
152(18)
43(2)
53(6)
75(8)
92(8)
110(11)
70(8)
83(8)
6972(11) 3732(6)
6816(10) 6341(7)
6424(16) 5062(24)
of this chloroimide in a DMF solution (at 22500,
–1
2
7000, and 30000 cm , ε = 315, 529, and 975 L/(mol cm),
respectively) is approximately half that of chloroimide
IV, although the intensities of UV/Vis bands of initial
triamines are the same. This is explained by the fact that
684(10) 7088(24) 6289(16)
154(4) 10389(9) 5008(13)
–214(11) 11035(19) 4059(10)
–863(10) 12293(19) 4114(16)
–1145(6) 12906(14) 5118(20)
–777(12) 12260(24) 6067(15)
–128(11) 11001(22) 6012(11)
1904(13) 5141(32) 5992(21)
961(13) 5193(23) 6074(17)
chloroamidation of [PtEnPyCl ]Cl yields not only
3
bright red chloroimide [Pt{NCl(CH ) NH }PyCl ] but
2
2
2
3
also products formed apparently upon oxidative dehy-
dration of ([Pt(HN=CHCH NH )PyCl ] or
[Pt(N≡CHCH NH )PyCl ]), which are yellow- rather
2
2
4
2
2
4
than red-colored [6, 12].
79(6)
253(25)
142(18)
In this work, the reaction of chlorine with plati-
2866(9)
7176(30) 5079(55)
num(IV) triamine containing N,N-dimethylethylenedi-
1915(17) 5472(45) 3997(25)
V
1129(1)
2997(2)
2358(2)
–62(2)
3453(2)
–999(5)
–708(5)
–2724(7)
–2213(7)
190(7)
amine with one reactive NH group gave a single bright
2
red
complex
identified
as
chloroimide
Pt(1)
Cl(1)
Cl(2)
Cl(3)
Cl(4)
N(1)
N(2)
C(1)
C(2)
C(3)
C(4)
7922(1)
9270(1)
6528(1)
9453(1)
7612(1)
8169(3)
6676(3)
7614(5)
6493(4)
5530(4)
7067(5)
6153(1)
5355(1)
5073(1)
7081(1)
7466(1)
5028(3)
6770(2)
5383(4)
5909(4)
7006(4)
7748(4)
21(1)
36(1)
40(1)
43(1)
39(1)
32(1)
28(1)
46(1)
45(1)
53(1)
51(1)
[Pt{(CH ) N(CH ) NCl}PyCl ] (IV). From chloroimide
3
2
2 2
3
solutions in CH CN and DMF, bright red crystals were
3
isolated; the former were studied by X-ray diffraction
(see below).
Previously, it was considered that chloroamidation
is a reversible reaction if it does not involve cleavage of
the metal ring. The reactions of chloroamides with HCl
(dechloroamidation) give rise to the initial complexes
[13]. However, currently irreversible chloroamidation
of [PtEnPy Cl ]Cl [14] is known in addition to the
2
2
2
–1575(8)
reversible
chloroamidation
of
tetramine
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 12 2008

REACTION OF CHLORINE WITH PLATINUM(IV) TRIAMINE CONTAINING
Table 3. Bond lengths (d) and bond angles (ω) in structures II–V
1867
Bond
d, Å
Angle
ω, deg
Angle
ω, deg
Bond
d, Å
III
Cl(2)Pt(1)Cl(3) 90.83(6)
N(3)Pt(1)N(2)
79.0(8)
Pt(1)–Cl(1)
2.3191(11)
Pt(1)–N(1)
Pt(1)–N(3)
Pt(1)–N(2)
Pt(1)–Cl(1)
Pt(1)–Cl(2)
Pt(1)–Cl(3)
2.047(4)
2.060(4)
2.119(4)
C(1)N(1)Pt(1) 107.5(4)
C(2)N(2)C(4) 108.1(5)
C(2)N(2)C(3) 110.0(5)
N(1)Pt(1)N(2) 177.6(8)
N(3)Pt(1)Cl(2) 168.1(6)
N(1)Pt(1)Cl(2) 88.1(4)
N(2)Pt(1)Cl(2) 94.0(6)
N(3)Pt(1)Cl(1) 80.8(7)
N(1)Pt(1)Cl(1) 88.9(4)
Pt(1)–Cl(2)
N(1)–C(1)
N(2)–C(4)
N(2)–C(3)
N(2)–C(2)
C(1)–C(2)
2.3216(11)
1.480(6)
1.492(6)
1.492(6)
1.506(5)
1.493(7)
2.3071(14) C(4)N(2)C(3) 106.2(5)
2.3121(14) C(2)N(2)Pt(1) 105.1(4)
2.317(2)
1.501(9)
C(4)N(2)Pt(1) 114.2(4)
C(3)N(2)Pt(1) 113.3(4)
N(1)–C(1)
N(2)Pt(1)Cl(1) 89.8(7)
Angle
ω, deg
N(2)–C(2)
N(2)–C(4)
N(2)–C(3)
N(3)–C(5)
N(3)–C(9)
C(1)–C(2)
C(5)–C(6)
C(6)–C(7)
C(7)–C(8)
C(8)–C(9)
1.490(8)
1.498(7)
1.500(7)
1.334(7)
1.344(7)
1.467(9)
1.367(8)
1.379(10)
1.378(10)
1.368(8)
C(5)N(3)C(9) 118.4(5)
C(5)N(3)Pt(1) 121.0(4)
C(9)N(3)Pt(1) 120.7(4)
C(2)C(1)N(1) 108.9(6)
C(1)C(2)N(2) 111.1(6)
N(3)C(5)C(6) 122.5(6)
C(5)C(6)ë(7) 119.3(6)
C(6)C(7)C(8) 118.2(6)
C(9)C(8)C(7) 119.7(6)
N(3)C(9)C(8) 121.9(6)
Cl(2)Pt(1)Cl(1) 89.6(3)
N(3)Pt(1)Cl(3) 96.5(6)
N(1)Pt(1)Cl(3) 84.9(4)
N(2)Pt(1)Cl(3) 96.2(6)
Cl(2)Pt(1)Cl(3) 93.8(4)
Cl(1)Pt(1)Cl(3) 172.9(4)
C(6)N(2)C(9) 111.4(14)
C(6)N(2)C(8) 107(2)
C(9)N(2)C(8) 104(3)
C(6)N(2)Pt(1) 115.8(13)
N(1)Pt(1)N(2)
84.59(13)
N(1)Pt(1)Cl(3) 88.49(11)
N(2)Pt(1)Cl(3) 94.37(11)
N(1)Pt(1)Cl(4) 177.80(10)
N(2)Pt(1)Cl(4) 93.34(9)
Cl(3)Pt(1)Cl(4) 90.95(5)
N(1)Pt(1)Cl(1) 91.16(11)
N(2)Pt(1)Cl(1) 175.47(9)
Cl(3)Pt(1)Cl(1) 87.06(5)
Cl(4)Pt(1)Cl(1) 90.93(4)
Angle
ω, deg
IV
C(9)N(2)Pt(1) 105(2)
N(1)Pt(1)Cl(2) 88.27(11)
N(1)Pt(1)N(3)
N(1)Pt(1)N(2)
93.1(2)
84.5(2)
Bond
d, Å
1.97(2)
C(8)N(2)Pt(1) 112.3(11)
C(7)N(3)Cl(4) 100.7(13)
N(2)Pt(1)Cl(2) 90.65(10)
Cl(3)Pt(1)Cl(2) 173.74(4)
Pt(1)–N(3)
Pt(1)–N(1)
Pt(1)–N(2)
N(3)Pt(1)N(2) 177.4(2)
N(1)Pt(1)Cl(1) 89.5(2)
2.031(6)
2.090(13)
2.349(8)
2.360(6)
2.381(7)
1.736(10)
1.495(10)
C(7)N(3)Pt(1) 104.7(11)
Cl(4)N(3)Pt(1) 112.6(10)
C(1)N(1)Pt(1) 122.4(10)
C(5)N(1)Pt(1) 117.5(10)
Cl(4)Pt(1)Cl(2) 92.49(5)
Cl(1)Pt(1)Cl(2) 87.66(4)
C(1)N(1)Pt(1) 108.7(3)
C(4)N(2)C(3) 107.0(4)
C(4)N(2)C(2) 109.9(4)
C(3)N(2)C(2) 107.6(4)
C(4)N(2)Pt(1) 113.4(3)
N(3)Pt(1)Cl(1) 87.76(13) Pt(1)–Cl(2)
N(2)Pt(1)Cl(1) 91.09(13) Pt(1)–Cl(1)
N(1)Pt(1)Cl(2) 88.4(2)
Pt(1)–Cl(3)
N(2)C(6)C(7)
96.3(13)
N(3)Pt(1)Cl(2) 86.88(13) Cl(4)–N(3)
N(2)Pt(1)Cl(2) 94.16(13) N(2)–C(6)
N(3)C(7)C(6) 109(2)
V
Cl(1)Pt(1)Cl(2) 174.13(5)
N(2)–C(9)
1.493(10)
1.513(9)
1.500(10)
ω, deg
Bond
d, Å
C(3)N(2)Pt(1) 114.1(3)
N(1)Pt(1)Cl(3) 175.57(14) N(2)–C(8)
N(3)Pt(1)Cl(3) 91.25(14) N(3)–C(7)
Pt(1)–N(1)
Pt(1)–N(2)
2.048(3)
2.126(3)
C(2)N(2)Pt(1) 104.7(2)
N(1)C(1)C(2) 109.1(4)
N(2)Pt(1)Cl(3) 91.16(13)
Cl(1)Pt(1)Cl(3) 91.68(6)
Angle
Pt(1)–Cl(3)
Pt(1)–Cl(4)
2.3138(11) C(1)C(2)N(2) 110.6(4)
2.3157(10)
N(3)Pt(1)N(1) 98.8(6)
[
PtPnPy Cl ]Cl [5]. No data for Pt(IV) triamines with a chloroimide IV with concentrated HCl at 100°ë
2 2 2
yielded complex VII (~80%) and V (~20%). According
five-membered metal ring are available. We studied the
reaction of chloroimide IV with concentrated HCl at
room temperature and obtained compound VI. Accord-
ing to X-ray diffraction data, this was the initial tri-
to X-ray diffraction data, these were the initial triamine
III [Pt(N,N-dimeEn)PyCl ]Cl and Pt(IV) diamine
3
[
Pt(N,N-dimtEn)PyCl )], respectively.
4
amine III (unit cell parameters a = 7.92, b = 8.32,
Ò = 29.28 Å, β = 93.67°, V = 1927 Å ). The reaction of the following results. The structure of III is ionic and
X-Ray diffraction studies of complexes III–V gave
3
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 12 2008

1
868
FEDOTOVA et al.
Table 4. Geometric parameters of hydrogen bonds in structures III and V
D–H···, Å
d, Å
DHA angle, deg Coordinates of A atom
D–H
H···A
D···A
III
N1–H1C···O(1x)
0.90
0.90
0.76
0.76
0.76
0.76
0.76
1.93
2.41
2.84
2.51
1.99
2.43
2.56
2.793(7)
3.267(5)
3.311(5)
3.267(5)
2.741(8)
3.166(5)
3.280(5)
160
159
122
174
172
164
160
x – 1, y – 1, z
N1–H1D···Cl(4)
O(1w)–H(2w)···Cl(4)
O(2w)–H(3w)···Cl(4)
O(2w)–H(4w)···O(3w)
O(3w)–H(5w)···Cl(4)
O(3w)–H(6w)···Cl(4)
–x + 1, y + 1/2, –z + 1/2
x, y + 1, z
–x, y + 1/2, –z + 1/2
V
N(1)–H(1A)···Cl(1)
N(1)–H(1B)···Cl(4)
0.90
0.96
2.45
2.58
3.305(4)
3.390(4)
158
149
–x, –y + 2, –z + 1
x – 1/2, –y + 3/2, z – 1/2
+
consists of [Pt{(CH ) N(CH ) NH }PyCl ] complex sponding equatorial planes. The conformation of the
3
2
2 2
2
3
–
dimethylethylenediamine-platinum metal rings in III
and V is gauche (the corresponding carbon atoms devi-
ate from the PtN(2) planes to different sides by 0.37 and
cations, Cl anions, and solvation water molecules com-
bined by hydrogen bonds (Table 4). Complexes IV and
V are neutral; complex V also contains hydrogen bonds
1
.30 Å in III and 0.33 and 0.34 Å in V) and that in com-
(
Table 4). All three structures are octahedral complexes
plex IV is envelope with the C(7) atom shifted from the
plane through the other atoms by 0.75 Å. The NPtN
angles in the ring in III and V are equal (84.5° and
with chelating N,N-dimethylethylenediamine ligands
typical of tetravalent platinum. Correspondingly, they
have roughly the same bond angles at Pt atoms (Table 3).
The Pt–Cl bonds in these three complexes are similar
irrespective of the trans-partner. However, note that the
Pt–N distances to the chelating ligand are substantially
8
4.6(1)°) and that in IV is somewhat smaller (79.0(8)°).
The structures of VI and VII are identical to that of III.
Thus, X-ray diffraction study of complex III has
dissimilar. The Pt(1)–N(1) bonds are usually somewhat shown that the reaction of chlorine with platinum(II)
shorter than Pt(1)–N(2), which is evidently due to the tetramine [Pt{(CH ) N(CH ) NH }Py ]Cl (II) results in
3
2
2 2
2
2
2
steric overcrowding of the N(1) atom caused by the removal of a pyridine molecule located in the trans-
presence of two methyl groups. Thus, in complex III, position to the N,N-dimethylethylenediamine NH2
Pt–N(1), 2.047(4) Å; Pt–N(2), 2.119(4) Å; in complex
group. The chlorine oxidation of tetramine II does not
V, Pt–N(1), 2.048(3) Å; Pt–N(2), 2.126(3) Å. In the tri- give platinum(IV) tetramine but gives the triamine
amine structure with unsubstituted ethylenediamine
–
[
Pt(N,N-dimeEn)PyCl ]Cl(III) with a Cl ion in the
3
[
PtEnPyCl ]Cl, the Pt–N(1) and Pt–N(2) bond lengths
3
trans-position to the NH group (or in the cis-position
2
are equal (2.05 Å) [8]. The presence of Cl substituent at
N(3) in the chelating ligand N,N-dimeEn in complex IV
results in insignificant shortening of the Pt–N(3) bond
to 1.97(2) Å). However, to within 3σ, this bond length
is equal to the corresponding Pt–N(H ) bond lengths in
complexes III and V. The N(3)–Cl(4) bond length in the
(CH ) N(CH ) NCl) ligand in complex IV (1.736(10) Å)
to the (ëH ) N group) (Fig. 1).
3
2
The reaction of III with chlorine gave the bright red-
colored chloroimide [Pt{(CH ) N(CH ) NCl]PyCl } (IV)
whose structure was confirmed by X-ray diffraction.
3
2
2 2
3
(
2
Chloroamidation of complex III is a reversible reac-
tion. The reaction of chloroimide IV with HCl at 20°ë
afforded the initial triamine III (complex VI). At 100°ë,
–
(
3
2
2 2
–
coincides with the N–Cl bond length in the NCl ligand the reaction gave ~80% of the initial triamine III and
of the dichloroimide [Pt(NH ) (NCl ) Cl]Cl [9]. The Pt– ~20% of platinum(IV) diamine [Pt(N,N-dimeEn)Cl ]
2
3
3
2 2
4
(
V). Somewhat unexpectedly, under these rigorous con-
N(Py) bonds in complexes III and IV have similar
lengths (2.060(4) and 2.031(6) Å, respectively). The
ditions of dechloroamidation of complex IV containing
–
planes of the pyridine rings in these complexes form the ligand (ëH ) N(CH )NCl) (refluxing at 100°ë), the
3 2 2
dihedral angles of 142.6° and 137.2° with the corre- five-membered ring was retained but pyridine mole-
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 12 2008

REACTION OF CHLORINE WITH PLATINUM(IV) TRIAMINE CONTAINING
1869
cules were partly removed. The reaction of HCl with
5. I. B. Baranovskii, P. A. Koz’min, T. N. Fedotova, et al.,
Zh. Neorg. Khim. 51 (2), 266 (2002) [Russ. J. Inorg.
Chem. 51 (2), (2002)].
the dichloroimide [Pt{(NCl(CH ) NCl}Py Cl ] at 100°ë
2
2
2
2
resulted in complete chelate destruction but the pyri-
dine molecules were retained (the reaction gave trans*-
6
. P. A. Koz’min, M. D. Surazhskaya, T. N. Fedotova, et al.,
Zh. Neorg. Khim. 46 (6), 920 (2001) [Russ. J. Inorg.
Chem. 46 (6), (2001)].
[
Pt(NH Py)* Cl*] [14]). Thus, the outcome of dechlo-
3
2 2
roamidation of Pt(IV) chloroimides depends on the type of
the chloroimide ligand and the metal ring geometry.
7
. T. N. Fedotova, A. N. Kravchenko, and S. G. Sakharov,
Zh. Neorg. Khim. 50 (4), 589 (2005) [Russ. J. Inorg.
Chem. 50 (4), (2005)].
8
9
. I. B. Baranovskii, M. A. Golubnichaya, and M. D. Surazhs-
ACKNOWLEDGMENTS
kaya, Zh. Neorg. Khim. 51 (12), 1994.
. M. Zipprich, H. Pritzkow, and J. Jander, Angew. Chem.
This work was supported by the Russian Foundation
for Basic Research, project no. 07-03-00707.
8
8 (7), 225 (1976).
1
1
1
0. G. M. Sheldrick, SHELXS97. Program for the Solution
of Crystal Structures (Univ. of Göttingen, Göttingen,
1
997).
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RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 12 2008