C-Cl bond cleavage of CH2Cl2 by the zinc(II) complex [Zn(phen)L2] (L = PhC (S) NP (O) (O i Pr)2-) with the formation of [Zn(phen)LCl] and CH2[PhC(S)NP(O)(OiPr)2]2

Article abstract of DOI:10.1016/j.inoche.2009.07.019

The reaction of [Zn(phen)L₂](L = PhC (S) NP (O) (O i Pr)₂^-) with CH₂Cl₂ leads to the formation of complex [Zn(phen)LCl] and S,S′-bis(benzimidothio-N-diisopropoxyphosphoryl)methane L-CH₂-L i

Full text of DOI:10.1016/j.inoche.2009.07.019

Inorganic Chemistry Communications 12 (2009) 913–915
Contents lists available at ScienceDirect
Inorganic Chemistry Communications
journal homepage: www.elsevier.com/locate/inoche
C–Cl bond cleavage of CH2Cl2 by the zinc(II) complex [Zn(phen)L2]
ðL ¼ PhCðSÞNPðOÞðOiPrÞꢀ2 Þ with the formation of [Zn(phen)LCl] and
CH2[PhC(S)NP(O)(OiPr)2]2
a
a
b
c
Damir A. Safin a, , Maria G. Babashkina , Axel Klein , Michael Bolte , Dmitriy B. Krivolapov ,
*
Igor A. Litvinov c
a Institut für Anorganische Chemie, Universität zu Köln, Greinstrasse 6, D-50939 Köln, Germany
b Institut für Anorganische Chemie J.-W.-Goethe-Universität, Frankfurt/Main, Germany
c Arbuzov Institute of Organic and Physical Chemistry, Arbuzov Street 8, 420088 Kazan, Russian Federation
a r t i c l e i n f o
a b s t r a c t
The reaction of [Zn(phen)L2] ðL ¼ PhCðSÞNPðOÞðOiPrÞꢀÞ with CH2Cl2 leads to the formation of complex
Article history:
2
[Zn(phen)LCl] and S,S0-bis(benzimidothio-N-diisopropoxyphosphoryl)methane L–CH2–L in high yields.
Using CHCl3 or CCl4 instead of CH2Cl2 does not lead to the formation of chlorine substituted products even
under reflux conditions. Compounds obtained were investigated by 1H and 31P{1H} NMR spectroscopy,
and microanalysis. The crystal structure of [Zn(phen)LCl] was elucidated by X-ray diffraction. The Zn(II)
atom in the complex is in a distorted tetragonal-pyramidal ClN2OS environment. The structure is stabi-
Received 15 June 2009
Accepted 19 July 2009
Available online 23 July 2009
Keywords:
Bond cleavage
Zn(II) complexes
Crystal structure
Phosphorylthiobenzamide
1,10-Phenanthroline
lized by the intermolecular hydrogen bonds of the type C–Hꢁ ꢁ ꢁCl–Zn and
pꢁ ꢁ ꢁp stacking interactions
between the phenanthroline rings.
Ó 2009 Elsevier B.V. All rights reserved.
Coordination compounds of Zn(II) with amidothiophosphate li-
gands RCðXÞNHPðYÞR02, which simultaneously contain donor atoms
of sulfur and oxygen (X – Y), remain poorly explored in compari-
son with dithioanalogues. Recently, we have reported on com-
plexes of Zn(II) with RC(S)NHP(O)(OiPr)2 ligands (R = Ph, p-BrPh,
NH2, iPrNH, tBuNH, c-C6H11NH, Et2N, c-C5H10N, c-OC4H8N, PhNH,
p-MeOPhNH, p-BrPhNH) [1], and interaction of some of these com-
plexes with 2,20-bipyridine (bipy) and 1,10-phenanthroline (phen)
[2]. The appearance of the hard donor carbonyl or phosphoryl
oxygen atoms in the coordination sphere of the central ion makes
it coordinatively unsaturated, which, in turn, can lead to the forma-
tion of heteroligand or polynuclear complexes with the central
atom having the coordination number 5 or 6.
previously described methods [2,6,7]. Complex [Zn(phen)LCl]
and
S,S0-bis(benzimidothio-N-diisopropoxyphosphoryl)methane
L–CH2–L were prepared by the following procedure: a suspension
of [Zn(phen)L2] in CH2Cl2 (10 mL) was stirred for 3 h, and after few
days colourless crystals of the complex were isolated (Scheme 1).
The solvent from the mother solution was removed in vacuo and
a precipitate of L–CH2–L was obtained [8]. Recrystallization of
[Zn(bipy)L2] from dichloromethane or acetone solutions, and
[Zn(phen)L2] from acetone solution lead to fine crystalline precip-
itates of the starting complexes. Unfortunately, we were not able to
get X-ray suitable crystals of [Zn(bipy)L2] and [Zn(phen)L2].
It should be noted that L–CH2–L was previously synthesized by
the reaction of the potassium salt KL with CH2I2 in boiling acetoni-
trile solution [9]. The yield of L–CH2–L was 69%. Reaction of
[Zn(phen)L2] with CH2Cl2 leads to the yields of 98% and 96% for
[Zn(phen)LCl] and L–CH2–L, respectively. Using CHCl3 or CCl4
instead of CH2Cl2 does not lead to the formation of chlorine substi-
tuted products even under reflux conditions.
On the other hand a promising strategy for inorganic crystal
engineering through combining noncovalent bonds such as van
der Waals,
p p stacking and hydrogen bonds with coordination
ꢁ ꢁ ꢁ
chemistry has attracted increasing attention in recent years [3–5].
In this work, we report on the synthesis of [Zn(phen)LCl] and
L–CH2–L ðL ¼ PhCðSÞNPðOÞðOiPrÞꢀ2 Þ using the reaction of the
starting complex [Zn(phen)L2] with CH2Cl2.
In the 31P{1H} spectrum of [Zn(phen)LCl] a singlet signal, with a
chemical shift characteristic for the amidophosphate environment
of the phosphorus nucleus [10], was observed at 6.6 ppm. This
signal is low-field shifted in comparison to the corresponding res-
onance of the parent complex [Zn(phen)L2] (d = 6.1 ppm [2]).
There is a singlet at ꢀ3.2 ppm in the 31P{1H} NMR spectrum of
L–CH2–L (d = ꢀ3 ppm in CCl4 + CD3C6D5 [9]).
N-Phosphorylated thiobenzamide HL, and complexes [ZnL2],
[Zn(bipy)L2] and [Zn(phen)L2] were prepared according to
* Corresponding author. Tel.: +49 221 470 2913; fax: +49 221 470 5196.
E-mail address: damir.safin@ksu.ru (D.A. Safin).
1387-7003/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved.
doi:10.1016/j.inoche.2009.07.019

914
D.A. Safin et al. / Inorganic Chemistry Communications 12 (2009) 913–915
Table 2
Ph
N
OiPr
OiPr
Ph
N
OiPr
OiPr
P
P
Selected bond lengths (Å) and bond angles (°) for [Zn(1,10-phen)LCl].
S
O
S
O
Bond lengths
CH2Cl2
Zn(1)–Cl(1)
Zn(1)–S(2)
Zn(1)–O(1)
Zn(1)–N(1A)
Zn(1)–N(4A)
S(2)–C(1)
2.2579(10) P(1)–O(1)
2.3869(9) P(1)–O(2)
2.0734(18) P(1)–O(3)
1.4805(19)
1.5577(18)
1.5582(18)
1.629(2)
2 [Zn(phen)L2]
2
Zn
N
+
CH2
S
N
Cl
O
P
OiPr
OiPr
2.121(2)
2.229(2)
1.723(2)
P(1)–N(1)
N(1)–C(1)
Ph
N
1.291(3)
[Zn(phen)LCl]
L-CH2-L
Bond angles
Cl(1)–Zn(1)–S(2)
Cl(1)–Zn(1)–O(1)
Cl(1)–Zn(1)–N(1A)
Cl(1)–Zn(1)–N(4A)
S(2)–Zn(1)–O(1)
S(2)–Zn(1)–N(1A)
S(2)–Zn(1)–N(4A)
O(1)–Zn(1)–N(1A)
O(1)–Zn(1)–N(4A)
N(1A)–Zn(1)–N(4A)
117.13(4)
100.72(7)
107.00(7)
98.58(7)
93.28(6)
134.90(7)
88.07(6)
87.11(8)
157.53(10)
76.27(9)
Zn(1)–S(2)–C(1)
O(1)–P(1)–O(2)
O(1)–P(1)–O(3)
O(1)–P(1)–N(1)
O(2)–P(1)–O(3)
O(2)–P(1)–N(1)
O(3)–P(1)–N(1)
Zn(1)–O(1)–P(1)
P(1)–N(1)–C(1)
S(2)–C(1)–N(1)
112.21(8)
Scheme 1. Preparation of [Zn(phen)LCl] and L–CH2–L.
107.40(10)
114.26(12)
117.34(12)
102.49(10)
106.92(11)
107.18(11)
128.60(11)
129.53(18)
129.37(18)
Table 1
Crystal data, data collection and refinement details for [Zn(phen)LCl].
Empirical formula
Formula weight
Crystal system
Space group
a (Å)
C25H27ClN3O3PSZn
581.38
Triclinic
ꢀ
P1
Torsion angles
7.8780(16)
10.525(2)
17.167(3)
99.61(3)
93.51(3)
108.20(3)
1323.4(5)
2
C(1)–S(2)–Zn(1)–Cl(1)
C(1)–S(2)–Zn(1)–O(1)
C(1)–S(2)–Zn(1)–N(1A)
108.20(10)
4.39(12)
ꢀ84.79(13)
Zn(1)–O(1)–P(1)–O(2) ꢀ159.33(15)
b (Å)
c (Å)
Zn(1)–O(1)–P(1)–O(3)
Zn(1)–O(1)–P(1)–N(1)
C(1)–N(1)–P(1)–O(1)
C(1)–N(1)–P(1)–O(2)
C(1)–N(1)–P(1)–O(3)
N(1)–C(1)–S(2)–Zn(1)
S(2)–C(1)–N(1)–P(1)
87.73(18)
ꢀ39.0(2)
28.3(3)
148.9(2)
ꢀ101.8(3)
ꢀ14.8(3)
0.4(4)
a
(°)
C(1)–S(2)–Zn(1)–N(4A) ꢀ153.15(12)
b (°)
P(1)–O(1)–Zn(1)–Cl(1)
P(1)–O(1)–Zn(1)–S(2)
P(1)–O(1)–Zn(1)–N(1A)
P(1)–O(1)–Zn(1)–N(4A)
ꢀ96.97(17)
21.44(18)
156.27(19)
114.3(2)
c
(°)
V (Å3)
Z
Dcalc (Mg mꢀ3
T (K)
)
1.459
293(2)
1.200
l
(mmꢀ1
)
F(0 0 0)
600
hmin–max (°)
Reflections collected
Unique reflections
2.2–28.0
11,923
6208
Observed reflections [I > 2.0
R indices (all data)
r(I)]
4261 (Rint = 0.039)
R1 = 0.0395, wR2 = 0.0984
Fig. 1. Molecular structure of the complex [Zn(phen)LCl]. Hydrogen atoms were
omitted for clarity.
The 1H NMR spectrum of [Zn(phen)LCl] contains a set of signals
for the (iPrO)2P(O) and Ph protons. There are also signals corre-
sponding to the polyaromatic chelate ligand. Analysis of the inte-
gral intensities of the proton signals testifies the suggested
complex structure of [Zn(phen)LCl], which was also proved by
the elemental analysis. In the 1H NMR spectrum of L–CH2–L be-
sides a set of signals for the (iPrO)2P(O) and Ph protons there is a
singlet for the CH2 protons at 4.49 ppm.
According to the X-ray data the complex [Zn(phen)LCl] crystal-
ꢀ
lizes in the triclinic space group P1 (Table 1) [11]. It contains a dis-
Fig. 2. Packing and hydrogen bonding in the crystal of [Zn(phen)LCl] along the a
axis (A), b axis (B) and c axis (C). H-atoms, not involved in hydrogen bonding, are
omitted for clarity.
torted tetragonal-pyramidal ZnClN2OS core (Fig. 1). The selected
bond lengths and angles are given in Table 2.

D.A. Safin et al. / Inorganic Chemistry Communications 12 (2009) 913–915
915
Table 3
does not show the same reaction. The latter might be explained
by the rigidity of the phen ligand compared to bipy and will be fur-
Hydrogen bond lengths (Å) and angles (°) for [Zn(1,10-phen)LCl]a.
ther explored in the future by applying other
a-diimine ligands.
D–Hꢁ ꢁ ꢁA
D–H
Hꢁ ꢁ ꢁA
2.64
2.74
Dꢁ ꢁ ꢁA
3.041(2)
3.561(4)
D–Hꢁ ꢁ ꢁA
107
147
Future work will be devoted to the application of the C–Cl bond
cleavage reaction to other substrates and the elucidation of the
reaction mechanism.
C(6A)–H(6A)ꢁ ꢁ ꢁCl(1)#1
0.93
0.93
C(10A)–H(10A)ꢁ ꢁ ꢁCl(1)#2
a
Symmetry codes: #1 2 ꢀ x, 1 ꢀ y, 2 ꢀ z; #2 1 ꢀ x, ꢀy, 2 ꢀ z.
Acknowledgments
Table 4
Selected
This work was supported by the Russian Science Support Foun-
dation. M.G.B. and D.A.S. thank DAAD for the scholarships (Fors-
chungsstipendien 2008/2009).
pꢁ ꢁ ꢁp
interactions for [Zn(1,10-phen)LCl]a.
Cg(I)b
Cg(J)
Cg–Cgc (Å)
Dihedral angles (°)
bd (°)
Cg(3)
Cg(3)
Cg(6)
Cg(3)#1
Cg(6)#1
Cg(6)#1
5.289(2)
3.8687(19)
3.679(2)
0
49.09
26.15
18.71
Appendix A. Supplementary material
0.79(15)
0
a
CCDC 730812 contains the supplementary crystallographic data
for [Zn(phen)LCl]. These data can be obtained free of charge from
The Cambridge Crystallographic Data Centre via http://
www.ccdc.cam.ac.uk/data_request/cif. Supplementary data associ-
ated with this article can be found, in the online version, at
doi:10.1016/j.inoche.2009.07.019.
Symmetry codes: #1 1 ꢀ x, ꢀy, 2 ꢀ z.
b
Cg(3): N(4A)–C(3A)–C(8A)–C(7A)–C(6A)–C(5A), Cg(6): N(1A)–C(2A)–C(3A)–
C(8A)–C(9A)–C(10A)–C(11A)–C(12A)–C(13A)–C(14A), where Cg refers to the ring
center of gravity and the numbers represent the rings involved in the interactions.
c
Cg–Cg: distance between ring centroids.
b: angle Cg(I) ? Cg(J) vector and normal to plane I.
D
References
Bond lengths (S)C–N (
are shortened (Table 2) and the C@S (
D
d ꢂ ꢀ0.07 Å) and P–N (
D
d ꢂ ꢀ0.04 Å)
D
d ꢂ 0.08 Å) and P@O
[1] F.D. Sokolov, D.A. Safin, N.G. Zabirov, P.V. Zotov, R.A. Cherkasov, Russ. J. Gen.
Chem. 75 (2005) 1919.
[2] D.A. Safin, F.D. Sokolov, H. Nöth, M.G. Babashkina, T.R. Gimadiev, J. Galezowska,
H. Kozlowski, Polyhedron 27 (2008) 2022.
[3] X.-X. Zhou, M.-S. Liu, X.-M. Lin, H.-C. Fang, J.-Q. Chen, D.-Q. Yang, Y.-P. Cai,
Inorg. Chim. Acta 362 (2009) 1441.
[4] S. Zhang, Y. Tang, Y. Su, J. Lan, R. Xie, J. You, Inorg. Chim. Acta 362 (2009) 1511.
[5] V. Balamurugan, M.S. Hundal, R. Mukherjee, Chem. Eur. J. 10 (2004) 1683.
[6] M.G. Zimin, N.G. Zabirov, R.M. Kamalov, A.N. Pudovik, Zh. Obshch. Khim. 56
(1986) 2352.
(
D
d ꢂ 0.02 Å) distances are considerably lengthened in comparison
with the corresponding interatomic distances reported for HL [10].
The vice versa situation is observed for the same interatomic
distances in comparison with the complex [ZnL2] [7]. The bond
lengths distribution in the ligand L confirms the superiority of
S-enolic tautomeric form S–C@N–P@O.
The six-membered Zn–O–P–N–C–S cycle has the asymmetrical
boat conformation. The maximal deviation of atoms from the least
square plane (LSP) of the cycle is observed for the oxygen
(ꢀ0.178(2) Å) and phosphorus (0.2051(9) Å) atoms. The five-
membered Zn–N–C–C–N cycle is almost planar. The maximal
deviation of atoms from LSP of the cycle is observed for the zinc
(0.0628(10) Å) and the nitrogen (ꢀ0.057(2) and ꢀ0.045(2) Å)
atoms.
There are intermolecular hydrogen bonds of the type C–Hꢁ ꢁ ꢁCl–
Zn in the crystal of [Zn(phen)LCl] (Fig. 2 and Table 3). These bonds
are formed between the two H-atoms of the phenanthroline ligand
of a molecule, and the chlorine atoms of two neighboring mole-
cules, while the Cl-atom forms two intermolecular hydrogen bonds
with protons of the polyaromatic ligands, corresponding to the
same two neighboring molecules. Additionally to the intermolecu-
[7] F.D. Sokolov, D.A. Safin, N.G. Zabirov, V.V. Brusko, B.I. Khairutdinov, D.B.
Krivolapov, I.A. litvinov, Eur. J. Inorg. Chem. (2006) 2027.
[8] Physical measurements: NMR spectra were obtained on
a Bruker Avance
300 MHz spectrometer at 25 °C. 1H and 31P NMR spectra (CDCl3) were recorded
at 299.948 and 121.420 MHz, respectively. Chemical shifts are reported with
reference to SiMe4 (1H) and 85% H3PO4 31P{1H}). Elemental analyses were
(
performed on
a CHNS HEKAtech EuroEA 3000 analyzer. Synthesis of
[Zn(phen)L2] and L–CH2–L: A suspension of [Zn(phen)L2] (0.1 g, 0.12 mmol)
in CH2Cl2 (10 mL) was stirred for 3 h. After 2 days colourless crystals of
[Zn(phen)LCl] appeared. The mixture was left for 2 days more. Then the
solution was decantated. Crystals of complex were isolated, washed by n-
hexane and dried in vacuo. [Zn(phen)LCl]. Yield: 0.067 g (98%). M.p. 163–
165 °C. 1H NMR: d = 1.18 (d, JH,H = 6.1 Hz, 12H, CH3), 4.66 (d sept,
3
3JPOCH = 7.7 Hz, JH,H = 6.2 Hz, 2H, OCH), 7.32–7.50, 7.87–8.04, 8.23–8.37,
3
8.46–8.60, 9.45–9.57 (m, 13H, Ph + phen) ppm. 31P{1H} NMR: d = 6.6 ppm.
Anal. Calcd. for C25H27ClN3O3PSZn (581.37): C, 51.65; H, 4.68; N, 7.23. Found:
C, 51.84; H, 4.49; N, 7.38%. The solvent from the mother solution was removed
in vacuo and the resulting precipitate of L–CH2–L was washed by n-hexane. L–
CH2–L. Yield: 0.070 g (96%). M.p. 126–127 °C (126 °C [4]). 1H NMR: d = 1.12 (d,
3JH,H = 6.3 Hz, 24H, CH3), 4.74 (m, 4H, OCH), 4.49 (s, 2H, CH2), 7.06–7.18, 7.25–
7.49, 7.61–8.04 (m, 10H, Ph) ppm. 31P{1H} NMR: d = ꢀ3.2 ppm (ꢀ3 ppm in
CCl4 + CD3C6D5 [4]). Anal. Calcd. for C27H40N2O6P2S2 (614.69): C, 52.76; H, 6.56;
N, 4.56. Found: C, 52.89; H, 6.47; N, 4.45%.
lar H-bonds
p p stacking interactions between the phenanthro-
ꢁ ꢁ ꢁ
line rings (Table 4) produce centrosymmetric dimers in the
crystal structure of [Zn(phen)LCl] (Fig. 2).
In summary, the novel Zn(II) complex [Zn(phen)LCl] was suc-
cessfully synthesized from the precursor [Zn(phen)L2] and CH2Cl2.
It was established that both chlorine atoms are substituted by L
with formation of [Zn(phen)LCl] and L–CH2–L. Using CHCl3 or
CCl4 instead of CH2Cl2 does not lead to the formation of chlorine
substituted products even under reflux conditions. Also, the similar
complex [Zn(bipy)L2] did not show this type of reaction under the
same conditions.
[9] N.G. Zabirov, F.D. Sokolov, R.A. Cherkasov, Zh. Obshch. Khim. 68 (1998) 1100.
[10] F.D. Sokolov, V.V. Brusko, N.G. Zabirov, R.A. Cherkasov, Curr. Org. Chem. 10
(2006) 27.
[11] The X-ray data for [Zn(phen)LCl] were collected on a Bruker Smart Apex II
diffractometer. Data were corrected for absorption using SADABS [12]
program. The structure was solved by direct method using the SHELXS97
[13] program and refined by the full matrix least-squares using SHELXL97
[13]. All non-hydrogen atoms were refined anisotropically. The hydrogen
atoms were located on difference map and refined isotropically.
[12] G.M. Sheldrick, SADABS, Program for Empirical X-ray Absorption Correction,
Bruker-Nonius, 1990–2004.
To date we can only speculate on the quite selective character of
this reaction and why the very similar bipy-containing complex
[13] G.M. Sheldrick, Acta Crystallogr. A64 (2008) 112.