Synthesis and molecular structure of the all-trans- and the trans-cis-isomers of dichlorodimethyltin complexes of phosphoric triamides

Article abstract of DOI:10.1016/j.ica.2010.12.060

Four new phosphoramidates with formula 4-RC₆H ₄C(O)NHP(O)(NH(CH(CH₃)₂)₂, R = H (1), OCH₃ (2), CH₃ (3), Cl (4) and their diorganotin(IV) complexes with formula SnCl₂(CH

Full text of DOI:10.1016/j.ica.2010.12.060

Inorganica Chimica Acta 368 (2011) 111–123
Contents lists available at ScienceDirect
Inorganica Chimica Acta
journal homepage: www.elsevier.com/locate/ica
Synthesis and molecular structure of the all-trans- and the trans–cis-isomers
of dichlorodimethyltin complexes of phosphoric triamides
⇑
Khodayar Gholivand , Sedigheh Farshadian
Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
a r t i c l e i n f o
a b s t r a c t
Article history:
Four new phosphoramidates with formula 4-RC6H4C(O)NHP(O)(NH(CH(CH3)2)2, R = H (1), OCH3 (2), CH3
(3), Cl (4) and their diorganotin(IV) complexes with formula SnCl2(CH3)2(X)2, X = 1 (5), 2 (6), 3 (7) and 4
(8) were synthesized and characterized by NMR, IR spectroscopy and elemental analysis. The spectro-
scopic properties of complexes were compared with those corresponding ligands. The molecular struc-
tures for 5, 5ꢀCH3CN, 6ꢀCH3CN, 7 and 8 were established by X-ray diffraction analysis and shown that
the tin atoms have a distorted octahedral coordination with trans-methyl groups. Two different all-trans
and cis–trans isomers were obtained by changing the crystallization solvent system. The existence of
CH3CN in molecular packing of trans–cis isomers might be a packing factor governing the orientation
of the ligands. Due to the presence of several hydrogen bond donors and acceptors on compounds,
extended hydrogen-bonded networks were observed. The structure of 2 was also determined and pos-
sesses two crystallographically independent molecules in asymmetric unit. On forming complex
6ꢀCH3CN, the ligand 2 shows shortening of C@O and P–N bond distances and increasing of P@O bond
length. Pseudopolymorphism of diorganotins in 5 and 5ꢀCH3CN is reported for the first time.
Ó 2010 Elsevier B.V. All rights reserved.
Received 21 November 2010
Received in revised form 20 December 2010
Accepted 21 December 2010
Available online 30 December 2010
Keywords:
Phosphoramidate
Diorganotin compounds
NMR spectroscopy
X-ray structures
Hydrogen bond
Isomers
1. Introduction
ethylphosphine oxide [26] showed that they usually form
dimethyltin dichloride complexes through the more basic P@O
Organotin(IV) compounds have been demonstrated to exhibit
wide biological activity [1–3]. Insofar as many phosphoryl ligands
are also noteworthy for the same reasons [4–6], a combination of
the two chemistries is an interesting line to pursue. Some of these
complexes have shown antitumor activity [7,8].
It has been shown that tin(IV) halide forms octahedral com-
plexes with phosphoryl ligands of the type R1R2R3P@O having
the general formula SnX4ꢀ2L [9–14] and two isomers, with the li-
gand L in cis or trans mutual orientations, are possible. The strength
of the Lewis basicity of the ligand, steric factors, solvent polarity
and temperature may be held responsible for the differences
observed [15–18]. Also, different isomers of octahedral diorgano-
tin, [Me2N(CH2)3]2SnF2ꢀ2H2O were observed in solution, although
X-ray diffraction analysis showed only the all-trans-configurated
octahedral in the solid state [19].
moiety. Also the products of the reactions of carbacylamidophos-
phates with SnCl2Me2 in 2:1 molar ratio were characterized by
X-ray structure analysis and the results were all-trans octahedral
complexes due to the fewer steric hindrance in the trans geometry.
To our knowledge, no crystal structure oftrans–cis-octahedral dior-
ganotin phosphoramidate has been published yet in the literature,
moreover only one paper reported crystallographically the all-trans
and trans–cis isomerism in octahedral diorganotin(1V) dihalide
complexes by solving the X-ray crystal structure of both isomers
[27].
On the other hand, the equimolar reaction between a car-
bamoylmethylphosphine oxide and SnCl2Me2 led to the formation
of five coordinate tin atoms with distorted trigonal bipyramidal
geometry, so the reagent ratio perhaps could influence the forma-
tion of 1:1 and 2:1 complexes.
Besides, carbacylamidophosphate and carbamoylmethylphos-
phine oxide derivatives, which have –C(O)XP(O)– in their molecu-
lar core units (X = NH and CH2, respectively) are potential
bidentate O,O-donor chelating ligands for metal ions, particularly
for lanthanides [20–22]. However, our previous studies on carbacy-
lamidophosphates [23–25] and Pannell studies on carbamoylm-
To continue our study in this field and in order to investigate
the effect of reagent ratio and choice of solvent on the coordina-
tion patterns of phosphoramidate diorganotin complexes four
new carbacylamidophosphates with formula 4-RC6H4C(O)NH-
P(O)(NH(CH(CH3)2)2, R = H (1), OCH3 (2), CH3 (3) and Cl (4) have
been synthesized. The ligands were reacted with SnCl2Me2 in
1:1 and 2:1 molar ratios in two different solvents, acetonitrile
and toluene, and diorganotin complexes 5–8 were formed. The
complexes were crystallized in various solvents and depending
⇑
Corresponding author. Tel.: +98 2182884422; fax: +98 2182883455.
E-mail address: gholi_kh@modares.ac.ir (K. Gholivand).
0020-1693/$ - see front matter Ó 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.ica.2010.12.060

112
K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
3
on the solvent, two different all-trans and trans–cis-octahedral
isomers were obtained. In addition to the molecular structure of
complexes, their crystal packings revealing supramolecular self
assembly were also reported. The crystal structure of 2 was char-
acterized and the bond lengths and angles were compared to
those related diorganotin complex (6ꢀCH3CN).
(s, CH), 54.83 (s, OCH3), 113.09 (s, Cmeta), 125.24 (d, JPC = 8.2 Hz,
C
ipso), 129.77 (s, Cortho), 162.42 (s, Cpara), 168.38 (s, C@O) ppm.
31P NMR (CDCl3): d = 7.47 (m) ppm.
2.2.3. N-(4-methyl benzoyl)-N0,N00-bis(isopropyl) phosphoric triamide
(3)
Yield: 70 %. M.p. 186–188 °C. Anal. Calc. for C14H24N3O2P
(297.34): C, 56.55; H, 8.13; N, 14.33. Found: C, 56.50; H, 8.19; N,
2. Experimental
14.35%. IR (KBr):
m = 3270 (s), 2965 (m), 1646 (s, C@O), 1611 (w),
1511 (w), 1424 (s), 1266 (w), 1208 (s, P@O), 1131 (m), 1032 (m),
2.1. Materials and methods
898 (m), 837 (w), 799 (w), 756 (w), 572 (w), 532 (w) cmꢁ1
.
1H
3
NMR (CDCl3): d = 1.13 (d, JHH = 6.4 Hz, 6H, CH3), 1.20 (d,
All the chemicals used are commercially available and were
used as received without further purification. 1H, 13C, 31P and
119Sn NMR specra were recorded on a Bruker Avance DRS 500 spec-
trometer at 500.13, 125.77, 202.46 and 186.50 MHz, respectively.
1H and 13C chemical shifts were determined relative to TMS. 31P
and 119Sn chemical shifts were measured relative to 85% H3PO4
and Sn(CH3)4 as external standards, respectively. Infrared (IR) spec-
tra were recorded on a Shimadzu model IR-60 spectrometer. Ele-
mental analysis was performed using a Heraeus CHN-O-RAPID
apparatus. Melting points were obtained with an Electrothermal
instrument.
3JHH = 6.4 Hz, 6H, CH3), 2.41 (s, 3H, CH3-Ph), 3.02 (dd, 2JPH = 8.4 Hz,
3
2H, NHamine), 3.56 (m, 2H, CH), 7.26 (d, JHH = 7.6 Hz, 2H, m-Ph),
3
2
7.83 (d, JHH = 8.1 Hz, 2H, o-Ph), 8.19 (d, JPH = 4.7 Hz, 1H, NHamide
)
ppm..13C NMR (CDCl3): d = 21.50 (s, p-CH3), 25.27 (d, JPC = 4.7 Hz,
3
3
CH3), 25.67 (d, JPC = 6.9 Hz, CH3), 43.38(s, CH), 127.78 (s, Cortho),
129.38 (s, Cmeta), 130.52 (d, JPC = 7.7 Hz, Cipso), 143.28(s, Cpara),
3
168.81 (s, C@O) ppm. 31P NMR (CDCl3): d = 6.95 (m) ppm.
2.2.4. N-(4-chlorobenzoyl)-N0,N00-bis(isopropyl) phosphoric triamide
(4)
Yield: 72%. M.p. 183–185 °C. Anal. Calc. for C13H21ClN3O2P
(317.76): C, 49.14; H, 6.66; N, 13.22. Found: C, 49.12; H, 6.70; N,
2.2. Synthesis of ligands
13.15%. IR (KBr):
m = 3335 (m), 3090 (w), 2970 (m), 1649 (s,
C@O), 1592 (w), 1494 (w), 1449 (s), 1288 (w), 1215 (s, P@O),
4-RC6H4C(O)NHP(O)Cl2 (R = H, OMe, Me and Cl) were synthe-
sized and purified using reported method [28].
1169 (w), 1132 (m), 1080 (w), 1040 (m), 1013 (m), 899 (m), 831
(w), 752 (m), 717 (w), 533 (m) cmꢁ1 1H NMR (CDCl3), d = 1.11
.
Compounds 1–4 were synthesized from the reaction of 4-
RC6H4C(O)NHP(O)Cl2 (R = H, OCH3, CH3 and Cl, respectively) with
isopropylamine in 1:4 molar ratio. The amine was added drop wise
to a CH3CN solution (30 ml) of 4-RC6H4C(O)NHP(O)Cl2 and stirred
at ꢁ1 °C. After 5 h, the products were filtered off and then washed
with distilled water and dried.
(d, 3J = 6.4 Hz, 6H, CH3), 1.19 (d, 3J = 6.4 Hz, 6H, CH3), 3.05 (dd,
2JPH = 8.1 Hz, 2H, NHamine), 3.51 (m, 2H, CH), 7.41(dd, 3JHH = 8.4 Hz,
3
5
6JPH = 1.2 Hz, 2H, m-Ph), 8.08 (dd, JHH = 8.4 Hz, JPH = 1.85 Hz, 2H,
o-Ph), 9.67 (br, 1H, NHamide) ppm. 13C NMR (CDCl3): d = 25.22 (d,
3JPC = 4.9 Hz, CH3), 25.63 (d, JPC = 6.8 Hz, CH3), 43.40 (s, CH),
3
4
128.71 (s,
C
meta), 129.78 (d, JPC = 5.4 Hz, Cortho), 131.78 (d,
Physical and spectroscopic data of the compounds 1–4 are pre-
sented below:
3JPC = 8.2 Hz, Cipso), 138.82 (s, Cpara), 168.36 (d, JPC = 6.3 Hz) ppm.
31P NMR (CDCl3): d = 7.41 (m) ppm.
2
2.2.1. N-(benzoyl)-N0,N00-bis(isopropyl) phosphoric triamide (1)
2.3. Synthesis of complexes
Yield: 80%. M.p. 196-198 °C. Anal. Calc. for
(283.31): C, 55.11; H, 7.83; N, 14.83. Found: C, 55.13; H, 7.80; N,
14.78%. IR (KBr): = 3270 (s), 2965(m), 1646 (s, C@O), 1492 (w),
C13H22N3O2P
Method A: one equivalent dimethyltin dichloride was added to
an acetonitrile solution of one equivalent of ligand and stirred at
room temperature. After 2 days, the solvent was allowed to evap-
orate slowly.
Method B: to a stirred solution of one equivalent of ligand, a
solution of one equivalent (CH3)2SnCl2 in toluene was added and
heated (50–60 °C) for 2 h and the resulting mixture was then stir-
red at room temperature. After 2 days, the mixture was filtered and
the resulting solution was evaporated.
m
1454 (s), 1378 (s), 1264 (w), 1206 (s, P@O), 1167 (w), 1134 (m),
1031 (m), 899 (m), 831 (w), 788 (w), 706 (m), 572 (w), 530 (w)
3
cmꢁ1
.
1H NMR (CDCl3): d = 1.11 (d, JHH = 6.4 Hz, 6H, CH3), 1.18
3
2
(d, JHH = 6.4 Hz, 6H, CH3), 3.04 (dd, JPH = 8.7 Hz, 2H, NHamine),
3.53 (m, 2H, CH), 7.44 (dd, JHH = 7.5 Hz, JHH = 7.9 Hz, 2H, m-Ph),
7.54 (t, JHH = 7.3 Hz, 1H, p-Ph), 7.99 (d, JHH = 7.3 Hz, 2H, o-Ph),
3
3
3
3
2
8.80 (d, JPH = 5.8 Hz, 1H, NHamide
)
ppm. 13C NMR (CDCl3):
3
3
d = 25.22 (d, JPC = 4.8 Hz, CH3), 25.63 (d, JPC = 6.9 Hz, CH3), 43.33
Above reactions were also carried out in 2:1 molar ratio of li-
gands/SnCl2Me2 and the same products were obtained.
(s, CH), 127.87 (s, Cortho), 128.57 (s, Cmeta), 132.47 (s, Cpara),
3
133.27 (d, JPC = 7.5 Hz, Cipso), 169.05 (s, C@O) ppm. 31P NMR
(CDCl3,): d = 7.49 (m) ppm.
2.3.1. Bis(N-benzoyl, N’,N’’-bis(isopropyl) phosphoric triamide)
dimethyl stannate(IV) dichloride (5)
2.2.2. N-(4-methoxy benzoyl)-N0,N00-bis(isopropyl) phosphoric
triamide (2)
This compound was obtained by the reaction of
SnCl2Me2. Yield: 52%. M.p. 170–172 °C. Anal. Calc. for
28H50Cl2N6O4P2Sn (786.27): C, 42.77; H, 6.41; N, 10.69. Found:
C, 42.74; H, 6.49; N, 10.75%. IR (KBr): = 3425 (w), 3282 (m),
1 with
Yield: 74%. M.p. 176–178 °C. Anal. Calc. for
(313.33): C, 53.67; H, 7.72; N, 13.41. Found: C, 53.71; H, 7.65; N,
13.45%. IR (KBr): = 3300 (m), 3120 (m), 2940 (m), 1634 (s,
C
14H24N3O3P
C
m
m
2970 (w), 1669 (s, C@O), 1597 (w), 1500 (w), 1451 (s), 1426 (s),
C@O), 1597 (s), 1509 (w), 1425 (s), 1311 (m), 1256 (s), 1210 (s,
1306 (w), 1257 (m), 1163 (s, P@O), 1151 (s), 1129 (s), 1056 (m),
P@O), 1173 (s), 1133 (m), 1028 (s), 1005 (m), 896 (m), 835 (m),
1022 (m), 903 (m), 839 (m), 797 (m), 711 (m), 626 (w), 544 (m)
3
775 (w), 687 (w), 541 (w), 498 (w) cmꢁ1
.
1H NMR (CDCl3):
cmꢁ1
.
1H NMR (CDCl3): d = 1.15 (d, JHH = 6.4 Hz, 12H, CH3), 1.21
3
3
3
d = 1.10 (d, 6H, JHH = 6.4 Hz, CH3), 1.17 (d, JHH = 6.4 Hz, 6H, CH3),
3.10 (dd, JPH = 8.4 Hz, 2H, NHamine), 3.53 (m, 2H, CH), 3.84 (s, 3H,
(d, JHH = 6.4 Hz, 12H, CH3), 1.31 (s, 2J(119Sn, 1H) = 88.6 Hz, 6H,
2
2
Sn(CH3)2), 3.06 (dd, JPH = 9.3 Hz, 4H, NHamine), 3.53 (m, 4H, CH),
3
3
3
3
OCH3), 6.90(d, JHH = 8.8 Hz, 2H, m-Ph), 8.08 (d, JHH = 8.8 Hz, 2H,
7.48 (dd, JHH = 7.6 Hz, JHH = 7.9 Hz, 4H, m-Ph), 7.58 (t,
o-Ph), 9.43 (d, JPH = 5.8 Hz, 1H, NHamide) ppm. 13C NMR (CDCl3):
3JHH = 7.3 Hz, 2H, p-Ph), 7.98 (d, JHH = 7.5 Hz, 4H, o-Ph), 8.98 (br,
2
3
3
3
3
d = 24.67 (d, JPC = 4.8 Hz, CH3), 25.09 (d, JPC = 6.9 Hz, CH3), 42.73
2H, NHamide) ppm. 13C NMR (CDCl3): d = 25.20 (d, JPC = 4.6 Hz,

K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
113
3
CH3), 25.57 (d, JPC = 6.9 Hz, CH3), 43.68 (s, CH), 127.87 (s, Cortho),
2.4. Crystal structure determination
3
128.83 (s, Cmeta), 132.38 (d, JPC = 7.9 Hz, Cipso), 133.05 (s, Cpara),
168.90 (s, C@O) ppm. 31P NMR (CDCl3): d = 5.98 (m) ppm. 119Sn
NMR (DMSO-d6): ꢁ238.25 ppm.
X-ray data of compounds 2, 5, 5ꢀCH3CN, 8 were collected on a
Bruker SMART 1000 CCD [29–31] and for compound 6ꢀCH3CN, 7
on a Bruker SMART APEX2 CCD area detector [32] with graphite-
monochromated Mo Ka radiation (k = 0.71073 Å). The structures
were refined with SHELXTL (for 2, 5, 5ꢀCH3CN, 7, 8) [33–35] and
SHELXL-97 [36] (for 6ꢀCH3CN) by full-matrix least-squares on F2. The
positions of hydrogen atoms were obtained from the difference
Fourier map. Crystal data and experimental details of the structure
determinations for compounds 2, 1b, 1bꢀCH3CN and 2bꢀCH3CN are
listed in Table 1 and for compounds 7 and 8 are listed in Table 2.
2.3.2. Bis(N-(4-methoxybenzoyl), N’,N’’-bis(isopropyl) phosphoric
triamide) dimethyl stannate(IV) dichloride (6)
This compound was obtained by the reaction of
SnCl2Me2. Yield: 45%. M.p. 157–159 °C. Anal. Calc. for
30H54Cl2N6O6P2Sn(846.32): C, 42.58; H, 6.44; N, 9.92. Found: C,
42.52; H, 6.54; N, 9.95%. IR (KBr): = 3400 (w), 3280 (m), 3000
2 with
C
m
(m), 1661 (s, C@O), 1603 (s), 1572 (w), 1515 (w), 1435 (s), 1406
(s), 1306 (w), 1253 (s), 1187 (m), 1161 (s, P@O), 1126 (s), 1092
(m), 1034 (s), 902 (m), 845 (m), 790 (w), 766 (w), 576 (w), 510
3
3. Results and discussion
(w) cmꢁ1
.
1H NMR (CDCl3): d = 1.15 (d, JHH = 6.4 Hz, 12H, CH3),
1.20 (d, 3JHH = 6.4 Hz, 12H, CH3), 1.29 (s, 6H, 2J(119Sn,
1H) = 88.9 Hz, Sn(CH3)2), 3.06 (br, 4H, NH), 3.53 (m, 4H, CH), 3.87
3.1. Synthesis and spectral characterization
3
(s, 6H, OCH3), 6.95 (d, JHH = 7.3 Hz, 4H, m-Ph), 7.94 (d,
3J = 8.3 Hz, 4H, o-Ph), 8.41 (br, 2H, NHamide) ppm. 13C NMR (CDCl3):
The reaction of 1 with SnCl2Me2 was first investigated. The ini-
tial aim of our investigation was to synthesize of penta and hexa
coordinated tin complexes by the reaction of one and two equiva-
lents of ligands with one equivalent SnCl2Me2, respectively. How-
ever, the resulting products were only hexa coordinated
complexes. When the above reactions were carried out using dif-
ferent solvents, such as acetonitrile and toluene only the hexacoor-
dinate tin complexes were isolated again irrespective of the solvent
(Scheme 1).
3
3
d = 20.90(s), 25.19 (d, JPC = 4.6 Hz, CH3), 25.54 (d, JPC = 7.1 Hz,
CH3), 43.70 (s, CH), 55.52 (s, OCH3), 114.09 (s, Cmeta), 124.80 (s,
3
C
ortho), 129.95 (d, JPC = 9.9 Hz, Cipso), 163.48 (s, Cpara), 168.33 (s,
C@O) ppm. 31P NMR (CDCl3): d = 6.18 (m) ppm. 119Sn NMR
(DMSO-d6): ꢁ237.03 ppm.
2.3.3. Bis(N-(4-methylbenzoyl), N’,N’’-bis(isopropyl) phosphoric
Crystallization of the product from the reaction of 1 with
SnCl2Me2 in various solvents led to different results. While crystal-
lization from CH3CN or toluene produced all-trans isomers, crystal-
lization from a mixture of acetonitrile and n-hexane yielded
essentially the trans–cis isomer, the first to be observed.
We analyzed other diorganotin derivatives containing the same
ligands with different para substituents on the phenyl ring in an at-
tempt to explain why the unexpected trans–cis configuration of Bis
(N-4-R-benzoyl, N’,N’’-bis(isopropyl)phosphoric triamide) di-
methyl stannate(IV) dichloride is the form experimentally ob-
served. The reactions of 3 and 4 with SnCl2Me2 in different
reagent ratio and solvents were attempted and crystallization in
the acetonitrile solution yielded all-trans octahedral tin complexes.
However, the reaction of 2 with SnCl2Me2 in toluene and recrystal-
lization of the product in acetonitrile/n-hexane solution was re-
sulted trans–cis isomer as observed in 5.
It is important to note that the molecular packing of both trans–
cis isomers contains molecules of CH3CN, which might be an
important packing factor governing the orientation of the ligands.
Therefore the conformation of the ligands probably results mainly
from packing forces. The structures of 5 and 5ꢀCH3CN are confor-
mational pseudopolymorphic and to the best of our knowledge
these are the first pseudopolymorphs of diorganotin compounds
that have been obtained until now.
triamide) dimethyl stannate(IV) dichloride (7)
This compound was obtained by the reaction of
SnCl2Me2. Yield: 44%. M.p. 159–161 °C. Anal. Calc. for
30H54Cl2N6O4P2Sn (814.32): C, 44.25; H, 6.68; N, 10.32. Found:
C, 44.23; H, 6.60; N, 10.35%. IR (KBr): = 3390 (m), 3285 (s),
3 with
C
m
2975 (m), 1673 (s, C@O), 1610 (m), 1515 (w), 1436 (s), 1366 (w),
1302 (w), 1253 (w), 1159 (s, P@O), 1124 (s), 1094 (m), 1045 (s),
902 (m), 840 (m), 791 (w), 750 (m), 573 (w), 510 (m) cmꢁ1
.
1H
3
NMR (CDCl3): d = 1.15 (d, JHH = 6.4 Hz, 12H, CH3), 1.20 (d,
3JHH = 6.4 Hz, 12H, CH3), 1.33 (s, 2J(119Sn, 1H) = 87.6 Hz, 6H,
Sn(CH3)2), 2.42 (s, 6H, CH3-Ph), 3.10 (dd, 2JPH = 9.5 Hz, 4H, NHamine),
3
3.50 (m, 4H, CH), 7.26 (d, JHH = .7.8 Hz, 4H, m-Ph), 7.87 (d,
2
3JHH = 8.1 Hz, 4H, o-Ph), 8.83 (d, JPH = 5.8 Hz, 2H, NHamide) ppm.
13C NMR (CDCl3): d = 20.96(s), 21.54 (s), 25.17 (d, JPC = 4.6 Hz,
3
3
CH3), 25.52 (d, JPC = 7.0 Hz, CH3), 43.69 (s, CH), 128.12 (s, Cortho),
3
129.79 (d, JPC = 7.8, Cipso), 143.66 (s, Cpara), 169.02 (s, C@O) ppm.
31P NMR (CDCl3): d = 5.70 (m) ppm.
2.3.4. Bis(N-(4-chlorobenzoyl), N’,N’’-bis(isopropyl) phosphoric
triamide) dimethyl stannate(IV) dichloride (8)
This compound was obtained by the reaction of
4 with
SnCl2Me2. Yield: 53%. M.p. 162–164 °C. C28H48Cl4N6O4P2Sn
(855.15): Anal. Calc. for C28H48Cl4N6O4P2Sn (855.15): C, 39.33; H,
5.66; N, 9.83. Found: C, 39.20; H, 5.60; N, 9.75%. IR (KBr):
The compounds 1–8 were characterized by means of IR and
multinuclear NMR spectroscopy. Some spectroscopic data of
organotin compounds and their corresponding ligands are listed
in Table 3.
m
= 3380 (w), 3250 (m), 2975 (m), 1651 (s, C@O), 1594 (m), 1495
(w), 1449 (s), 1302 (w), 1260 (w), 1189 (m), 1168(s, P@O), 1125
(s), 1100 (m), 1039 (m), 1010 (m), 897 (m), 796 (m), 752 (m),
The methyl protons of the two isopropyl groups appear as two
different doublets (3JHH = 6.4 Hz). 1H NMR spectra of free ligands
show a triplet (which is actually two overlapping doublets) corre-
sponds to the amine (isopropyl) protons at 3.00–3.10 ppm
(2JPH = 8.1–8.7 Hz) due to the presence of two different types of
N–H protons in the molecules. This value increases comparatively
from the free ligands 1–4 to complexes, which is in line with the
shortening of the P–N bonds. The same results were also observed
in the previous reported organotin complexes of phosphonic diam-
ides [37,38].
3
719 (w), 534 (w) cmꢁ1
.
1H NMR (CDCl3): d = 1.15 (d, JHH = 6.4 Hz,
3
12H, CH3), 1.21 (d, JHH = 6.4 Hz, 12H, CH3), 1.29 (s, 6H, 2J(119Sn,
2
1H) = 87.0 Hz, Sn(CH3)2), 3.06 (dd, JPH = 9.4 Hz, 4H, NHamine), 3.50
(m, 4H, CH), 7.45 (d, 3JHH = 7.9 Hz, 4H, m-Ph), 7.96 (d, 3JHH = 8.0 Hz,
4H, o-Ph), 8.88 (br, 2H, NHamide
)
ppm. 13C NMR (CDCl3):
3
3
d = 14.16(s), 25.14 (d, JPC = 4.6 Hz, CH3), 25.50 (d, JPC = 6.9 Hz,
CH3), 43.83 (s, CH), 129.12 (s, Cortho), 129.51 (s, Cmeta), 130.83 (d,
3JPC = 8.3 Hz, Cipso), 139.56 (s, Cpara), 167.96 (s, C@O) ppm. 31P
NMR (CDCl3): d = 5.62 (m) ppm.

114
K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
Table 1
Crystal data collection and structure refinement parameters for complexes 2, 5, 5ꢀCH3CN and 6ꢀCH3CN.
Compound
2
5
5ꢀCH3CN
6ꢀCH3CN
Empirical formula
Formula weight
T (K)
Crystal system
Space group
a (Å)
C
14H24N3O3P
C28H50Cl2N6O4P2Sn
786.27
100(2)
monoclinic
P21/c
18.8529(10)
13.0348(7)
15.5011(8)
90
99.2700(10)
90
3759.5(3)
4
1.389
0.946
C30H53Cl2N7O4P2Sn
827.32
100(2)
monoclinic
C2/c
12.2916(11)
14.3903(13)
22.330(2)
90
91.589(2)
90
3948.2(6)
4
1.392
0.905
C32H57Cl2N7O6P2Sn
887.38
100(2)
monoclinic
P21/n
10.0536(5)
23.9795(11)
17.9173(8)
90
101.2390(10)
90
4236.7(3)
4
1.391
0.852
313.33
100(2)
triclinic
ꢀ
P1
8.3973(3)
11.8993(4)
17.5883(6)
96.3030(10)
93.6580(10)
106.5460(10)
1666.14(10)
4
b (Å)
c (Å)
a
(°)
b (°)
c
(°)
V (Å3)
Z
Density (Mg/m3)
1.249
0.178
l
(mmꢁ1
)
F(0 0 0)
672
1624
1712
1840
Crystal size (mm)
h (°)
Reflections collected/unique
Rint (%)
0.13 ꢂ 0.11 ꢂ 0.08
1.17–27.00
16232/7286
2.02
0.35 ꢂ 0.25 ꢂ 0.08
1.09–29.00
59043/10001
3.75
0.27 ꢂ 0.19 ꢂ 0.16
1.82–30.11
13803/5774
5.58
0.45 ꢂ 0.35 ꢂ 0.25
1.44–28.00
46701/10218
3.04
Completeness to h (%)
Maximum/minimum transmission
Data/restraints/parameters
Goodness-of-fit (GOF) on F2
100.0
100.0
99.0
99.8
0.989/0.980
7286/0/379
1.013
0.922/0.792
10001/0/404
1.005
0.865/0.801
5774/0/219
0.971
0.810/0.701
10218/0/475
1.003
Final R indices [I > 2
r
(I)]
R1 = 0.0505
wR2 = 0.1352
R1 = 0.0602
wR2 = 0.1515
0.822 and ꢁ0.433
R1 = 0.0229
wR2 = 0.0499
R1 = 0.0323
wR2 = 0.0517
0.695 and ꢁ0.601
R1 = 0.0447
wR2 = 0.0778
R1 = 0.0832
wR2 = 0.0883
0.613 and ꢁ0.625
R1 = 0.0237
wR2 = 0.0547
R1 = 0.0310
wR2 = 0.0578
0.936 and ꢁ0.415
R indices (all data)
Largest diff. peak/hole (e Å3)
Table 2
Crystal data collection and structure refinement parameters for complexes 7 and 8.
O
O
P
Compound
Formula
7
8
NH(CH(CH3)2)
NH(CH(CH3)2)
n
R
C
SnCl2Me2
C
30H54Cl2
C28H48Cl4N6O4P2Sn
HN
N6O4P2Sn
814.32
296(2)
monoclinic
P21/c
13.4136(11)
9.9554(7)
15.6336(13)
102.321(2)
2039.6(3)
2
1.326
0.874
844
0.19 ꢂ 0.16 ꢂ 0.15
1.55–30
34653/5932)
2.83
99.9
0.880/0.852
Formula weight
Temperature (K)
Crystal system
Space group
a (Å)
b (Å)
855.15
100(2)
monoclinic
P21/c
13.1841(7)
9.8125(6)
15.5437(9)
101.8300(10)
1968.2(2)
2
1.443
1.041
876
0.26 ꢂ 0.17 ꢂ 0.12
1.58–30.51
25461/5994
4.07)
99.8
0.8853/0.7736
n = 1 or 2
1-4
CH3CN
or CH3C6H5
R
R = H
1, 5,
c (Å)
OCH3 2, 6,
CH3
Cl
b (°)
V (Å3)
3, 7,
4, 8
Z
Density (Mg/m3)
Absorption coefficient (mmꢁ1
F(0 0 0)
)
NHCH(CH3)2
NH
Cl
CH3
Crystal size (mm)
h (°)
Reflections collected/unique
O
P
O
O
Sn
(H3C)2HCHN
NHCH(CH3)2
O
P
Rint (%)
H3C
(H3C)2HCHN
Cl
Completeness to h (%)
Maximum/minimum
transmission
Data/restraints/parameters
Goodness-of-fit (GOF) on F2
HN
5932/40/235
1.001
5994/0/227
1.026
5-8
Final R indices [I > 2
r(I)]
0.0286
0.0265
wR2 = 0.0713
R1 = 0.0405
wR2 = 0.0804
1.120 and 0.743
wR2 = 0.0582
R1 = 0.0412
wR2 = 0.0629
0.668 and ꢁ0.450
R indices (all data)
R
Largest diff. peak/hole (e Å3)
Scheme 1. Preparation pathway of diorganotin(IV) phosphoramidate 5-8.
In the 13C NMR spectra, two CH3 carbons of the two isopropyl
groups are not equivalent and we observe two 3J(P,C) coupling con-
stants in ligands and complexes. The ipso carbon atoms of phenyl
rings in compounds 1–4 show 3J(P,Caromatic) coupling constants in
the range from 5.4 Hz (4) to 7.7 Hz (3) that increase to 7.8–
9.9 Hz in complexes 5-8.
As shown in Table 3, chemical shift of 31P for compounds 1–4 are
very close to each other and are in the range of 6.95–7.49 ppm. 31
P
NMR spectra of complexes indicate that by coordinating to Sn, this
parameter shows a small shift to higher fields due to disruption of
the PO
p interaction as a result of complex bond formation. This rel-
atively small upfield shift (Table 3) is demonstrative of a sizeable N

K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
115
Table 3
Spectroscopic NMR and IR data of the compounds.
Compound
d
31P
2(JPNH
(Hz)
)
2(JPNH
(Hz)
)
2J(119SnH)
(Hz)
3J(P, Caliphatic
(Hz)
)
3J(P, Caromatic
(Hz)
)
d(C@O)
(ppm)
m
(N–H)
m
(C@O)
m
(P@O)
amine
amide
(ppm)
(cmꢁ1
3270
)
(cmꢁ1
1646
)
(cmꢁ1
)
1
2
3
4
5
6
7
8
7.49
8.7
8.4
8.4
8.1
9.3
–
5.8
5.8
4.7
br
–
4.8
6.9
4.8
6.9
4.7
6.9
4.9
6.8
4.6
6.9
4.6
7.1
4.6
7.0
4.6
6.9
7.5
8.2
7.7
8.2
7.9
9.9
7.8
8.3
169.00
168.38
168.81
168.39
168.90
168.33
169.02
167.96
1206
7.47
6.95
7.41
5.98
6.18
5.70
5.62
3300
3270
3335
3425
3400
3390
3380
1634
1646
1649
1669
1661
1673
1651
1210
1208
1215
1163
1161
1159
1168
–
–
–
br
88.6
88.9
87.6
87.0
br
9.5
9.4
5.8
br
P inductive effect by means of electron donation from the nitrogen
centers to compensate the loss of electron density around phospho-
rus following complexation [39]. The same results have been ob-
served in our previous studied organotin complexes with ligands
of the type RC(O)NHP(O)(R0)2 [23–25]. However the downfield
chemical shifts in comparison to that of free ligands were observed
for RP(O)(NHR0)2 (R = alkyl, aryl) [34,35] and ((CH3)3CPh)2P(O)CH2-
C(O)N(CH(CH3)2)2 organotin complexes [26].
Fig. 1. Molecular structure and atom-labeling scheme for 2 (40% probability ellipsoids).

116
K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
The 119Sn chemical shifts of compounds 5 and 6, at ꢁ238.25 and
mentary materials, Table S1. Compound 2 exists as two conformers
in crystalline lattice. They are due to different spatial orientation of
isopropyl amine groups. In one of them two amino hydrogen atoms
are syn to the carbonyl group, but not in the other (Fig. 1).
The difference is also described by comparison of correspond-
ing torsion angles in two conformers. Torsion angles P(1)–N(3)–
C(9)–C(10) and P(1)–N(3)–C(9)–C(11) are ꢁ114.23(16)° and
122.17(17)°, whereas P(2)–N(5)–C(23)–(C25) and P(2)–N(5)–
C(23)–C(24) are 52.8(2)° and 175.62(14)°, respectively.
The sum of the surrounding angles around N(1) and N(4) are
slightly lower than sp2 angles, 357.9 and 359.3°, respectively and
as usual for such species, they are nearly planar. The other nitrogen
atoms in the molecules are distorted from planarity and the sum of
the angles around them are in the range of 349.2–355.01°.
As expected, the P–Namide bond lengths (Namide is the nitrogen
atom of P(O)N(H)C(O) moiety) are longer than the P–Namine dis-
tances (Namine is the nitrogen atom of P(O)NR moiety), because of
ꢁ237.03 ppm, respectively, are consistent with six-coordinate tin
complexes [40].
In the IR spectra, the N–H stretching vibrations in ligands result
in an absorption in the range of 3270–3335 cmꢁ1. In the organo-
tin(IV) complexes this band shifts to higher energy suggesting an
important influence of the coordination to tin and are consistent
with the presence of different hydrogen bonding of N–H moiety
in ligands (N–HꢀꢀꢀO) and complexes (N–HꢀꢀꢀCl).
IR spectra of compounds 1–4 show that the
m
(P@O) and
m
(C@O)
frequencies are in the range of 1206–1215 cmꢁ1 and 1634–
1649 cmꢁ1, respectively. The spectra of their organotin compounds
showed a large decreasing for
comparison to their related ligands. The negative significant shift
of the (P@O) in the spectra of complexes with respect to the free
m(P@O) and increasing for m(C@O) in
m
ligands, is in accordance with the coordination of the phosphoryl
oxygen atom to tin and confirmed by X-ray diffraction studies.
the resonance interaction of the Namide with the C@O
p system that
causes a partial multiple bond character in C–Namide (the C–Namide
bond lengths are shorter than the C–Namine bond lengths, Table S1).
All of these P–N bonds are shorter than the typical P–N single bond
length (1.77 Å) [41]. This is likely due to the electrostatic effects
3.2. Crystal structure of 4-CH3OC6H4C(O)NHP(O)(NH(CH(CH3)2)2 (2)
Single crystals of 2 suitable for single crystal X-ray diffraction
analysis were obtained during washing the product with distilled
water. Selected structural parameters are summarized in Supple-
(polar bonds) which overlap with P–N
r bond [42].
The P@O and C@O bonds are anti and the bond lengths fall
within the norms for these linkages in phosphoramidates [43,44].
The phosphorus atoms have a distorted tetrahedral configuration
with angles in the range of 105.48(7)–113.93(7)° for P(1),
103.29(7)–116.68(8)° for P(2).
Table 4
Hydrogen bond geometries for compound 2 [Å, °].
D–H–A
d(D–H)
d(HꢀꢀꢀA)
d(DꢀꢀꢀA)
\DHA
The hydrogen bonding data are given in Table 4. Each indepen-
dent molecule is connected to its symmetrically similar molecule
via two equal –C@OꢀꢀꢀH–N– hydrogen bonds and produces a cen-
trosymmetric dimer in the crystal lattice. The observed hydro-
gen-bonding pattern is of the DA:::AD type (A = H bond acceptor
and D = H bond donor). These dimeric aggregates are connected
to each other via –P@OꢀꢀꢀH–N– hydrogen bonds to form a 1D poly-
mer (Fig. 2).
N(1)–H(1)ꢀꢀꢀO(4) [x, y, z]
N(2)–H(2)ꢀꢀꢀO(2) [x, y, z]
N(3)–H(3)ꢀꢀꢀO(2)
0.87
0.86
0.83
1.95
2.43
2.11
2.815(2)
2.925(2)
2.937(2)
173
117
174
[2 ꢁx, ꢁy + 2, ꢁz + 1]
N(4)–H(4)ꢀꢀꢀO(1) [x, y, z]
N(6)–H(6)ꢀꢀꢀO(5) [3 ꢁx, ꢁy + 1, ꢁz]
C(4)–H(4A)ꢀꢀꢀO(3)
0.88
0.84
0.95
0.95
0.98
0.95
1.98
2.10
2.714
2.350
2.554
2.259
2.844(2)
2.928(2)
3.413(2)
3.191(2)
3.495(2)
3.192(2)
170
167
131.0
147.2
161.1
167.4
C(3)–H(3A)ꢀꢀꢀO(4)
C(22)–H(22C)ꢀꢀꢀO(1)
C(17)–H(17A)ꢀꢀꢀO(1)
Besides the strong hydrogen bonds, the packing of 2 is further
stabilized by a system of weaker intermolecular C–HꢀꢀꢀO hydrogen
bonds as listed in Table 4. The methoxy group of the first indepen-
dent molecule acts as an acceptor H bond and is involved in CHꢀꢀꢀO
interaction with hydrogen atom on a benzene of its symmetrically
related molecule and vice versa, forming an eight-membered
{ꢀꢀꢀOCCH}2 synthon (by DA:::AD type double hydrogen bond).
However, the methoxy group of the second molecule is C–HꢀꢀꢀO
interaction donor for the phosphoryl group of the first molecule.
Furthermore, the oxygen atoms of phosphoryl groups, O1 and O4
are involved in CHꢀꢀꢀO hydrogen bonds with hydrogen atoms on
aromatic rings of the second and first molecules, respectively
(Fig. 3). All the geometrical data of above CHꢀꢀꢀO interactions fall
into the normal range of the CHꢀꢀꢀO hydrogen bonding [45]. The
centroid-to-centroid distance between two parallel phenyl rings
of the first and second molecules are 3.713 and 3.753 Å, respec-
tively, indicating the presence of
p–p stacking interactions. The
CHꢀꢀꢀO H-bonding and
p–p
stacking interactions assemble the 1-
D chains to form a 3-D supramolecular architecture.
3.3. Crystal structures of SnCl2(CH3)2[C6H5C(O)NHP(O)
(NHCH(CH3)2)2]2 (5) and SnCl2(CH3)2[C6H5C(O)NHP(O)
(NHCH(CH3)2)2]2ꢀCH3CN (5ꢀCH3CN)
Suitable single crystals for X-ray diffraction analysis of 5 and
5ꢀCH3CN were obtained by crystallization of 5 from toluene and
acetonitrile/n-hexane, respectively. The molecular structures for
5 and 5ꢀCH3CN are shown in Figs. 4 and 5, respectively and selected
bond lengths and angles are listed in Supplementary materials,
Tables S2 and S3, respectively. Pseudopolymorphs 5 and 5ꢀCH3CN
Fig. 2. View of the NHꢀꢀꢀO hydrogen bonding in the crystal structure of 2. The two
symmetry-independent forms are shown in green and blue. The dashed lines
represent the hydrogen bonds. (For interpretation of the references to colour in this
figure legend, the reader is referred to the web version of this article.)

K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
117
Fig. 3. Intermolecular p–p and CHꢀꢀꢀO interactions in 2.
Fig. 5. Molecular structure and atom-labeling scheme for complex 5ꢀCH3CN (50%
probability ellipsoids).
172.76(5)° ([O(1)#Sn(1)–Cl(1)] and [O(1)–Sn(1)–C(l)#1]). So, the
deviation of C–Sn–C in 5 (10.18°) is larger than the corresponding
one found for 5ꢀCH3CN (6.03°). In our previous studied diorganotin
compounds of ligands with –C(O)NHP(O)– skeleton, the trans an-
gles around tin atoms were exactly linear (180°), the molecules
were centerocymetric and the central tin atom occupied a center
of inversion [23–25]. But two different Sn–O distances
(2.2031(11) and 2.2224(10) Å) and also two different P–O–Sn an-
gles (145.48(7) and 150.09(7)°) can be observed in 5. The shorter
Sn–O distance corresponds to the larger P–O–Sn angle (and re-
verse). These Sn–O bond lengths are a little longer than the Sn–O
covalent bond [2.038–2.115 Å] [46–49]. We also note larger differ-
ences in Sn–Cl bond lengths. Thus, the Sn–Cl(2) bond is the longest
at 2.7106(4) Å amongst all the Sn–Cl bonds observed in this study
and those found for diorganotin compounds and is comparable
with the Sn–Cl found in diorganotin compounds with bridged Cl
atoms between two tin centers [50]. 5ꢀCH3CN shows three couples
of identical Sn–ligand distances. The Sn–C bond lengths [2.1075(17)
and 2.1107(16) Å in 5 and 2.106(3) Å in 5ꢀCH3CN] are consistent
with those reported in other organotin(IV) complexes.
Fig. 4. Molecular structure and atom-labeling scheme for complex 5 (50% proba-
bility ellipsoids).
crystallize in the same crystal system (monoclinic) but in different
space groups (P21/c and C2/c, respectively).
The tin atoms of 5 and 5ꢀCH3CN are hexacoordinated by two car-
bon, two oxygen and two chlorine atoms and show distorted all-
trans and trans–cis octahedral configuration, respectively. The trans
bond angles around Sn atom of 5 are 169.82(7) [C(1S)–Sn(1)–C(2S)],
172.14 [O(1)–Sn(1)–O(3)] and 173.847(13)° [Cl(1)–Sn(1)–Cl(2)],
being smaller than the ideal value of 180°. The corresponding an-
gles (178.52(15), 177.50(6) and 177.78(6)°, respectively) that ob-
served for the all-trans-SnCl2(CH3)2[C6H5P(O)(NHCH(CH3)2)2]2
[38] were closer with this value. In pseudopolymorph 5.CH3CN
the trans bond angles are 173.97° [C(14)#1–Sn(1)–C(14)] and

118
K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
complex (located on two-fold axis) and half of acetonitrile solvent
disordered over two-fold axis (Fig. 6).
In all of organotin compounds 5–8, each molecule has six NH
bonds that two NHamide are involved in hydrogen bonding with
the chlorine atoms of the same molecule, so two six-membered
rings around tin are formed. These rings that made up six different
elements coming from five different groups of the main group
(group 1 (H), group 14 (Sn), group 15 (N, P), group 16 (O), group
17 (Cl)) were also observed in diorganotin phosphonic diamides
[37,38] with this different that in them one of the two N–H of iso-
propylamines on each phosphonic diamide is involved in hydrogen
bonding. Furthermore, in 5, the three N–Hamine participate in inter-
molecular hydrogen bonding with the chlorine and carbonyl
groups of neighboring molecules (Table 5) and two dimensional
polymeric structures were obtained parallel to the bc plane.
In the crystal structure, weak C–HꢀꢀꢀO [C(5)–H(5A)ꢀꢀꢀO(3):
d(H5AꢀꢀꢀO3) = 2.699 Å, d(C5ꢀꢀꢀO3) = 3.606 Å and \C5–H5AꢀꢀꢀO3
= 159.98°] and C–HꢀꢀꢀCl [C(25)–H(25B)ꢀꢀꢀCl(1): H25AꢀꢀꢀCl1 = 2.833 Å,
C25ꢀꢀꢀCl1 = 3.761 Å and \C25–H25BꢀꢀꢀCl1 = 158.02°] intermolecular
interactions are also found. These data are in agreement with those
reported in the literature [45,52]. In addition, an intramolecular
NꢀꢀꢀO short contact is observed between the oxygen of one carbonyl
group and a Namine (d(N3ꢀꢀꢀO2) = 2.945 Å).
Fig. 6. Independent part of unit cell contains half of complex (located on two-fold
axis) and half of acetonitrile solvent disordered over two-fold axis in 5ꢀCH3CN.
Although the difference is not very significant, the Sn–O bonds
are slightly longer in the trans–cis complex (2.2250(9) Å) compared
to its all-trans indicating a greater trans influence of the chlorine li-
gands compared to the phosphoramidate ligands.
In 5ꢀCH3CN, hydrogen bonded chains along the c axis are
formed by the intermolecular double N2–H2ꢀꢀꢀO2 hydrogen bonds
and disordered acetonitrile molecules are located in the spaces
between the chains (Fig. 7). There is no hydrogen bonding be-
tween the polymer chains and acetonitrile molecules. Indeed,
there are only van der Waals interactions between neighbouring
In 5 the different ligands are cis to each other and C–Sn–O, C–Sn–
Cl and O–Sn–Cl bond angles are in the range of 84.70(5)–98.37(3)°.
In 5ꢀCH3CN the cis angles are in the range of 85.57(10) [C(14)–
Sn(1)–O(1)#1] to 99.76(4)° [Cl(1)–Sn(1)–Cl(1)#1]. On going from
the all-trans to the trans–cis isomer, no significant differences are
observed in the P@O distances (1.4948(11) and 1.4971(11) Å for 5
and 1.493(2) Å for 5ꢀCH3CN). These bond lengths are slightly short-
er than the values found for SnCl2(CH3)2[C6H5P(O)(NHCH(CH3)2)2]2
(1.505(2) and 1.502(2) Å) [38]. These changes presumably reflect
the effect of the addition of –NHC(O)– group. As a consequence,
the P–Namine bonds in these complexes are shorter due to increased
hyperconjugation of the nitrogen lone pairs to the phosphorus atom
[51]. These results are consistent with the 31P NMR chemical shift
chains and the solvent molecules establish only weak C–Hꢀꢀꢀ
p
interactions [d(C6ꢀꢀꢀCg) = 3.485 Å (Cg: center of CN bond),
d(H6AꢀꢀꢀCg) = 2.804 Å and \(C6–H6AꢀꢀꢀCg) = 129.56°] with the host
that is comparable to those found in the literature [53]. The intra-
molecular NꢀꢀꢀO short contacts (d(N3ꢀꢀꢀO2) = 3.010 Å) is also pres-
ent in the structure.
differences observed between
(NHCH(CH3)2)2]2 [38].
5
and SnCl2(CH3)2[C6H5P(O)-
3.4. Crystal structure of SnCl2(CH3)2[p-CH3OC6H4C(O)NHP(O)
(NHCH(CH3)2)2]2ꢀCH3CN (6ꢀCH3CN)
The P@O distance (1.489(3) Å) in o-C6H4(SnClMe2)2.(Me2N)3PO
[50] with three P–Namine bonds is shorter than those of 5–8 due
to lack of interaction between carbonyl group with nitrogen center
in the former and hence better electron donation from the nitrogen
center to the phosphoryl group.
Some of the carbons of isopropyl groups in 5 (C(9), C(22) and
C(23)) are disordered over two positions with relative occupancies
0.6/0.4. Independent part of unit cell of 5ꢀCH3CN contains half of
Monoclinic crystals of 6ꢀCH3CN were grown from a concen-
trated acetonitrile/n-hexane solution at room temperature. The
molecular structure of complex 6ꢀCH3CN with the atom-labeling
scheme are depicted in Fig. 8 and a selection of bond lengths and
angles is given in Supplementary materials, Table S4. The tin atom
shows a distorted trans(C, C) cis(O, O) cis(Cl, Cl) octahedral
configuration.
Table 5
Hydrogen bonds for compounds 5, 5ꢀCH3CN, 6ꢀCH3CN, 7 and 8 [Å, °].
Compound
D–H–A
d(D–H)
d(HꢀꢀꢀA)
d(DꢀꢀꢀA)
\DHA
5
N(1)–H(1 N)ꢀꢀꢀCl(2) [x, y, z]
0.91
0.91
0.88
0.86
0.82
0.90
0.90
0.79
0.85
0.84
0.80
0.74
0.80
0.87
0.87
0.88
0.88
2.38
2.13
2.42
2.77
2.11
2.54
2.10
2.17
2.41
2.37
2.21
2.56
2.32
2.45
2.51
2.41
2.43
3.2642(14)
3.0276(18)
3.2695(14)
3.6122(15)
2.8806(18)
3.356(3)
2.994(3)
2.945(2)
3.238(1)
3.194(1)
3.001(2)
3.279(2)
3.105(2)
3.2908(17)
3.3714(18)
3.2568(15)
3.3114(16)
165
166
162
166
157
151
172
168
166
165
169
165
171
163
171
161
175
N(3)–H(3 N)ꢀꢀꢀO(4) [x, y + 1, z]
N(4)–H(4 N)ꢀꢀꢀCl(1) [x, y, z]
N(5)–H(5 N)ꢀꢀꢀCl(2) [x, ꢁy + 3/2, z + 1/2]
N(6)–H(6 N)ꢀꢀꢀO(2) [x, y ꢁ 1, z]
5ꢀCH3CN
6ꢀCH3CN
N(1)–H(1)ꢀꢀꢀCl(1) [x, y, z]
N(2)–H(2)ꢀꢀꢀO(2) [ꢁx, ꢁy, ꢁz + 1]
N(6)–H(1N6)ꢀꢀꢀO(2) [ꢁx ꢁ 1/2, y ꢁ 1/2, ꢁz + 3/2]
N(4)–H(1N4)ꢀꢀꢀCl(1) [x, y, z]
N(1)–H(1N1)ꢀꢀꢀCl(2) [x, y, z]
N(3)–H(1N3)ꢀꢀꢀO(5) [ꢁx ꢁ 1/2, y + 1/2, ꢁz + 3/2]
N(2)–H(1N2)ꢀꢀꢀO(6) [ꢁx + 1/2, y + 1/2, ꢁz + 3/2]
N(5)–H(1N5)ꢀꢀꢀO(3) [ꢁx + 1/2, y ꢁ 1/2, ꢁz + 3/2]
N(1)–H(1 N)ꢀꢀꢀCl(3) [1 ꢁ x, ꢁy, ꢁz]
N(3)–H(3 N)ꢀꢀꢀCl(3) [2 ꢁ x, y + 1/2, z + 1/2]
N(1)–H(1)ꢀꢀꢀCl(1) [ꢁx, ꢁy, ꢁz]
7
8
N(3)–H(3)ꢀꢀꢀCl(1) [ꢁx, y + 1/2, ꢁz + 1/2]

K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
119
Fig. 7. View of the H-bonded chains along c axis produced by N2–H2ꢀꢀꢀO2 H-bonds in 5ꢀCH3CN with disordered acetonitrile molecules between chains. Hydrogen atoms are
omitted for clarity.
Fig. 8. Molecular structure and atom-labeling scheme for complex 6ꢀCH3CN (50% probability ellipsoids).
In trans position of the two oxygen atoms are chlorines and dis-
tances are correlated: the shorter is Sn–O, the longer is Sn–Cl (per-
haps ‘trans effect’). In this complex in spite of 5 the longer Sn–O
distance corresponds to the larger P–O–Sn angle.
The bond angles O–Sn–Cl (177.44(3) and 179.19°) deviate
slightly from the idealized value, 180°, and the deviation is smaller
than the corresponding one found for 5ꢀCH3CN. On the other hand
the O–Sn–O bond angle 90.97(4)° is closer to 90° than one in
5ꢀCH3CN, 99.79(4)°. In fact the smallest bond angles for the couples
of cis atoms is that relevant to the C(1)–Sn(1)–O(1) angle
(84.43(6)°); whereas the largest value is, that for C(2)–Sn(1)–
Cl(1) (93.87(5)°).
The O–Sn–O–P torsion angles found are O(1)–Sn(1)–O(1)–
P(1) = 121.1(2)° for 5ꢀCH3CN, O(1)–Sn(1)–O(4)–P(2) = 136.83(11)°
and O(4)–Sn(1)–O(1)–P(1) = ꢁ164.71(14)° for 6ꢀCH3CN. This indi-
cates the more coplanar arrangement of the ligand with the tin
atom in 6ꢀCH3CN than 5ꢀCH3CN. The O–PꢀꢀꢀP–O torsion angle is
29.26° in 6ꢀCH3CN, 96.29° in 5ꢀCH3CN and 162.19° in 5.
The bond angles around phosphorus P1 (in the range from
105.47(8) to 116.26(7)°) and P2 (104.92–118.26°) indicate dis-
torted tetrahedral geometry, with the larger values displayed by
the O–P–N angles (Table S4). The P@O bond lengths in this mole-
cule (1.4951(11) and 1.4993(12) Å) are longer than the normal
P@O bond length (1.45 Å) [41] and that of the corresponding

120
K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
Fig. 9. 2D hydrogen bonded layered network in 6ꢀCH3CN in the ab plane. (The H atoms were omitted for clarity).
ligand, 2. This lengthening is consistent with the low stretching
frequency observed in the IR spectra may also explain the differ-
ences observed in the 31P NMR chemical shifts between the free
and bound ligands in solution.
interaction between C(25)–H(25A) and nitrile bond [d(C25ꢀꢀꢀCg) =
3.596 Å, d(H25AꢀꢀꢀCg) = 2.893 Å and \C25–H25AꢀꢀꢀCg = 129.51].
Furthermore, C–HꢀꢀꢀCl–Sn weak interaction between C(24) of
methoxy group and Cl(2) also stabilize the structure, the
C(24)ꢀꢀꢀCl(2) and H(24A)ꢀꢀꢀCl(2) distances are 3.601 and 2.869 Å,
respectively.
On forming complex 6ꢀCH3CN, the ligand 2 also shows shorten-
ing of C@O and P–N bond distances. The C@O bond lengths de-
crease from 1.234(2) in 2 to 1.224(2) and 1.2185(19) in 6ꢀCH3CN.
The P–Namide bonds decrease from 1.6946 (14) and 1.6951(14) Å
in 2 to 1.6745(14) and 1.6756 (14) Å in 6ꢀCH3CN. Also, the P–Namine
bond lengths decrease from 1.6243(13)–1.6470(16) Å to
1.6108(14)–1.6207(14) Å. These observations represent the
increasing of the P–N bond order as observed in our previous phos-
phoramidate complexes [54]. The carbon–nitrogen bond adjacent
to the carbonyl group (N1–C1 and N4–C17) with internuclear dis-
tances of 1.379(2) and 1.383(2) Å is considerably longer than the
bond lengths in ligand (1.365(2) Å).
The asymmetric unit of compound 6ꢀCH3CN contains one
complex and one CH3CN molecule. The main axis of the N(1S)–
C(2S)–C(1S) acetonitrile molecule in 5ꢀCH3CN is coplanar with
the C–Sn–C plane and is nearly perpendicular to the plane of the
Cl(1)Cl(1A)O(1)O(1A), the CH3 group being directed towards the
inside. However in 6ꢀCH3CN the angles of this axis with C–Sn–C
and the plane of Cl(1)Cl(2)O(1)O(4) are 78.75 and 57.16°,
respectively.
As mentioned in Section 3.3., the CH3CN molecule in 5ꢀCH3CN is
disordered over two positions participating in the host–guest C–Hꢀ
ꢀ
p bond. On the other hand, the crystal structure refinement re-
veals that the guest molecule in 6ꢀCH3CN occupies one principal
site and the molecule in that site participates in both C–Hꢀꢀꢀ
p
and
C–HꢀꢀꢀCl bonding, suggesting that the additional bond effectively
locks each CH3CN molecule on a particular site within the channel.
3.5. Crystal structures of SnCl2(CH3)2[p-CH3C6H4C(O)NHP(O)
(NHCH(CH3)2)2]2 (7) and SnCl2(CH3)2[p-ClC6H4C(O)NHP(O)
(NHCH(CH3)2)2]2 (8)
Colorless crystals of 7 and 8 were obtained from a concentrated
CH3CN solution at room temperature. Figs. 10 and 11 show ORTEP
representation of the molecular structure for complex 7 and 8,
respectively, and their selected bond distances and angles are
listed in Supplementary materials, Table S5. These complexes are
isostructural with space group P21/c and Z = 2. The molecules are
centrosymmetric and identical ligands are in trans positions with
the bond angles of 180.0° around Sn atom. The different ligands
are cis to each other and C–Sn–O, C–Sn–Cl and O–Sn–Cl bond an-
gles do not deviate from 90° by more than 1.91° and 2.02° for 7
and 8, respectively. The Sn–C bond lengths are 2.097(2) Å in 7
and 2.1063(18) Å in 8 that are quite close to those reported in
the literature. The Sn–Cl bond lengths (2.5909(6) and 2.5922(4) Å
in 7 and 8, respectively) lying in the normal covalent radii 2.37–
2.60 Å [55–57]. The Sn–O bond distances (2.2303(13) and
2.2300(11) Å) are longer than the sum of the covalent bond radii
of Sn and O [46–49], but are considerably shorter than the sum
of their van der Waals radii of 3.71 Å [58].
Due to the presence of hydrogen bond acceptor methoxy
groups, 6ꢀCH3CN exhibits a crystal packing, which is entirely dif-
ferent from that of 5ꢀCH3CN. In 6ꢀCH3CN, in addition to carbonyl
groups, the oxygen atoms of methoxy groups also participate in
intermolecular hydrogen bonds with N–H groups (Table 5),
forming infinite layers parallel to the ab plane (Fig. 9). The cen-
troid–centroid distance between aromatic planes in the layers is
4.133 Å, indicating no strong
p–p stacking interactions exist in
complex. The layer stacking forms channels along the c axis
filled by acetonitrile molecules. The acetonitrile molecule is
linked to the channel via
interaction [d(C(2S)ꢀꢀꢀCl(2) = 3.641 Å, d(H(2SC)ꢀꢀꢀCl2) = 2.905 Å
and \C(2S)–H(2SC)ꢀꢀꢀCl(2) = 134.26°] and also the C–Hꢀꢀꢀ
a
weak C(2S)–H(2SC)ꢀꢀꢀCl(2)–Sn(1)
p

K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
121
O6) = 2.407 Å and \(C4–H4AꢀꢀꢀO2) = 156.73°] and the para chlorine
atoms of 8 participate in weak intramolecular C(8)–H(8A)ꢀꢀꢀCl(2)
interactions [d(C8ꢀꢀꢀCl2) = 3.564 Å, d(H8AꢀꢀꢀCl2) = 2.868 Å and
\(C8–H8AꢀꢀꢀCl2) = 128.73°]. Intermolecular C–HꢀꢀꢀCl interactions
between Cl(1) and H atoms belonging to the disordered methyl
groups are also found in 8.
3.6. Comparison of the structures for complexes 5, 5ꢀCH3CN, 6ꢀCH3CN,
7 and 8
The Sn–O bond lengths in above complexes decrease in the fol-
lowing order: 6ꢀCH3CN > 7 ꢃ 8 > 5ꢀCH3CN > 5. The smallest Sn–O
bond distances for compounds 1b and 1bꢀCH3CN is presumably
due to the less steric hindrance. Interestingly, in the all-trans con-
figurated diorganotins, the Sn–O distance is shorter and the Sn–Cl
distance is longer (Table 6). Apparently, this is the result of both
the trans configuration and the chlorine atoms being involved in
intermolecular ClꢀꢀꢀH–N hydrogen bonding in all-trans compounds.
The Sn–O distances in these compounds are comparable with the
Sn–O distances found in o-C6H4(SnClMe2)2.(Me2N)3PO and (Ph2-
ClSnCH2)2.(Me2N)3PO [50,59].
Fig. 10. The unit-cell contents for 7. Atoms are represented by thermal ellipsoids
(p = 50%). The C(13) and C(14) atoms are disordered over two positions with
occupation ratio 0.6:0.4.
The Sn–O–P angles are not linear and the all trans-octahedral
complexes exhibit greater Sn–O–P angles than trans–cis ones.
Among them 7 (153.83(9)°) and 8 (153.20(8)°) have the largest va-
lue. In all-trans isomers the tin atoms are nearly eclipsed with the
Namidic of the phosphoramide (torsional angle Sn–O–P–Namidic
17.04(14) and -9.43(16)° in 5, 4.7(3)° in 7 and 3.59(19)° in 8).
The corresponding torsion angles are 31.9(2)° in 5ꢀCH3CN,
ꢁ25.51(15) and 44.25(13)° in 6ꢀCH3CN.
In the crystal structure of 7, the carbon atoms of one of the iso-
propyl groups of each ligand (C(13) and C(14)) are disordered over
two positions with occupation ratio 0.6:0.4. The same disorder was
also observed for C(12), C(13) carbon atoms of 8.
As a result of intermolecular N–HꢀꢀꢀCl hydrogen bonds (Table 5)
two dimensional polymeric chains are obtained in the crystal pac-
kings of 7 and 8. Also, the carbonyl groups are involved in CHꢀꢀꢀO
intermolecular hydrogen bonds as acceptors [C(4)–H(4A)ꢀꢀꢀO(6) in
7: d(C4ꢀꢀꢀO6) = 3.317 Å, d(H4AꢀꢀꢀO6) = 2.465 Å and \(C4–H4AꢀꢀꢀO6)
= 152.37°; C(4)–H(4A)ꢀꢀꢀO(2) in 8: d(C4ꢀꢀꢀO2) = 3.301 Å, d(H4Aꢀꢀꢀ
In these diorganotin compounds, like phosphoric triamide li-
gands, the C@O and P@O groups adopt anti configuration as a re-
sult of the dipole–dipole repulsion. The O–P–N–Ccarbonyl torsion
Fig. 11. Molecular structure and atom-labeling scheme for complex 8 (50% probability ellipsoids).

122
K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
Table 6
Selected bond lengths (Å) angles (°) for complexes.
Compound
d(Sn–O)
d(Sn–Cl)
d(P@O)
d(P–Namide
)
d(P–Namine
)
d(C@O)
\(C–Sn–C)
\(P–Sn–O)
5
2.2031(11)
2.2224(10)
2.5244(4)
2.7106(4)
1.4948(11)
1.4971(11)
1.6840(13)
1.6842(13)
1.6163(13)
1.6187(13)
1.6139(14)
1.6145(13)
1.611(2)
1.2217(19)
1.2202(19)
169.82(7)
145.48(7)
150.09(7)
5ꢀCH3CN
6ꢀCH3CN
2.2250(19)
2.5725(8)
1.493(2)
1.685(2)
1.219(3)
173.97(18)
171.44(7)
146.88(12)
1.614(2)
2.2640(11)
2.2670(11)
2.5495(4)
2.5615(4)
1.4951(11)
1.4993(12)
1.6745(14)
1.6756(14)
1.6167(15)
1.6202(14)
1.6108(14)
1.6129(17)
1.6036(19)
1.6129(17)
1.6115(15)
1.6202(15)
1.224(2)
1.2185(19)
148.85(7)
143.23(7)
7
8
2.2303(13)
2.2300(11)
2.5906(6)
2.5922(4)
1.4907(15)
1.4947(12)
1.6813(16)
1.6829(14)
1.213(2)
180
180
153.83(9)
153.20(8)
1.2222(2)
angles are in the range ꢁ159.56(12) to 172.4(2)°. The O–CꢀꢀꢀP–O
torsion angles are in the range 162.82–179.29°.
The sums of angles around nitrogen amidic in the complexes
vary in the range of 359.29 –360.02° and these atoms are perfectly
sp2 hybridized. The sums of angles around other nitrogen atoms
are in the range of 350.97–359.83° and some of them are
pyramidal.
ration between the crystal structure of ligand 2 and its related
organotin (6ꢀCH3CN) showed that coordination of the ligand is fol-
lowed by a number of structural perturbations such as the changes
in the bond lengths and bond angles. Some perturbations in the IR
and NMR spectra of coordinated ligands were also occurred upon
complexation.
As observed in 2, in these complexes P–Namide bond lengths
are longer than the P–Namine bonds in agreement with solution
Appendix A. Supplementary material
data that (2JPNH amine is greater than 2(JPNH amide
) . Also, the angles
)
CCDC 709117, 785718, 785720, 785719, 742001 and 785716
contain the supplementary crystallographic data for 2, 5,
5ꢀCH3CN, 6ꢀCH3CN, 7 and 8, respectively. These data can be ob-
tained free of charge from The Cambridge Crystallographic Data
Centre via www.ccdc.cam.ac.uk/data_request/cif. Supplementary
data associated with this article can be found, in the online version,
at doi:10.1016/j.ica.2010.12.060.
OPNamide are lower than the angles OPNamine
.
The differences in the coordination environment of the tin atom
and different para substituents on the phenyl ring are not dramat-
ically reflected in the bond lengths within the OPNCO skeleton. The
phosphorus–oxygen bond distances are in the range of
1.4907(15)–1.4993(12) Å. The shortest P–Namide bond lengths are
observed for 6ꢀCH3CN (1.6745(14) and 1.6756(14) Å) and in other
complexes this value vary between 1.6813(16) and 1.685(2) Å
(Table 6).
References
Over and above the conformational differences between all-
trans and trans–cis isomers, they form quite distinct patterns in
their intermolecular contacts. While the chlorine atoms of all trans
molecules participate in intermolecular interactions with NHamine
groups, the NHamineꢀꢀꢀCl hydrogen bonding is completely absent
in the trans–cis isomers and their NHamine groups are involved in
NHꢀꢀꢀO hydrogen bonds with carbonyl groups (and methoxy groups
in 6ꢀCH3CN). The same hydrogen bond is also found in 5, however
the structures of 7 and 8 comprise intermolecular C–HꢀꢀꢀO@C
hydrogen bonds instead. Only in 5 and 5ꢀCH3CN, without substitu-
ent on the phenyl rings, oxygen of carbonyl group and Namine are
close enough to form NꢀꢀꢀO short contact.
[1] L. Pellerito, L. Naggy, Chem. Rev. (Washington, DC, US) 224 (2002) 111–150.
[2] M. Gielen, E.R.T. Tiekink (Eds.), Metallotherapeutic Drugs and Metal-Based
Diagnostic Agents, The Use of Metals in Medicine, Wily, New York, 2005.
[3] M. Gielen, A.G. Davies, K.H. Pannell, E.R.T. Tiekink (Eds.), Tin Chemistry:
Fundamentals, Frontiers, and Applications, Wily, 2008.
[4] J.L. Lefferts, K.C. Molloy, J.J. Zuckerman, I. Haiduc, C. Guta, D. Ruse, Inorg. Chem.
19 (1980) 1662.
[5] N. Singh, M. Megharaj, W.P. Gates, G.J. Churchman, J. Anderson, R.S. Kookana, R.
Naidu, Z. Chen, P.G. Slade, N. Sethunathan, J. Agric. Food Chem. 51 (2003) 2653.
[6] P.H. Terry, A.B. Borkovec, J. Agric. Food Chem. 21 (1973) 500.
[7] E.V. Grigoriev, N.S. Yashina, A.A. Prischenko, M.V. Livantsov, V.S. Petrosyan, W.
Massa, K. Harms, S. Wocadlo, L. Pellerito, Appl. Organomet. Chem. 9 (1995) 11.
[8] E.V. Grigorev, N.S. Yashina, A.A. Prischenko, M.V. Livantsov, V.S. Petrosyan, L.
Pellerito, M.J. Schafer, Appl.Organomet. Chem. 7 (1993) 353.
[9] M.T. Ben Dhia, M.A.M.K. Sanhoury, L.C. Owono Owono, M.R. Khaddar, Mol.
Struct. 892 (2008) 103.
[10] E. Le Coz, J.E. Guerchais, Bull. Soc. Chim. Fr. 1 (1971) 80.
4. Conclusions
[11] S.J. Ruzicka, A.E. Merbach, Inorg. Chim. Acta 20 (1976) 223.
[12] D. Fàrsaiu, R. Leu, P.J. Ream, J. Chem. Soc., Perkin Trans. 2 (2001) 427.
[13] S.E. Dann, A.R.J. Genge, W. Levason, G. Reid, J. Chem. Soc., Dalton Trans. (1997)
2207.
[14] C.H. Yoder, L.A. Margolis, J.M. Horne, J. Organomet. Chem. 633 (2001) 33.
[15] S.J. Ruzicka, A.E. Merbach, Inorg. Chim. Acta 22 (1977) 191.
[16] D. Tudela, V. Fernàndez, J.D. Tornero, J. Chem. Soc., Dalton Trans. (1985) 1281.
[17] J. Rupp-Bensadon, E.A.C. Lucken, J. Chem. Soc., Dalton Trans. (1983) 495.
[18] S.N. Semenov, E.Yu. Maltsev, I.G. Timokhin, A.A. Drozdov, S.I. Troyanov,
Mendeleev Commun. (2005) 205.
[19] N. Pieper, C. Klaus-Mrestani, M. Schürmann, K. Jurkschat, M. Biesemans, I.
Verbruggen, J.C. Martins, R. Willem, Organometallics 16 (1997) 1043.
[20] M. Borzechowska, V. Trush, I. Turowska-Tyrk, W. Amirkhanov, J.
Legendziewicz, J. Alloys Compd. 341 (2002) 98.
[21] K.O. Znovjyak, O.V. Moroz, V.A. Ovchynnikov, T.Yu. Sliva, S.V. Shishkina, V.M.
Amirkhanov, Polyhedron 28 (2009) 3731.
Some new phosphoramidates and their diorganotin complexes
have been synthesized. Irrespective of the solvent and reagent ratio
only the hexacoordinate tin complexes were obtained. The struc-
ture of ligand 2 and complexes 5, 5ꢀCH3CN, 6ꢀCH3CN, 7 and 8 have
been determined by X-ray diffraction analysis. The results showed
that the solvent of crystallization plays an important role in the
formation of all-trans or cis–trans isomers. So, while crystallization
from CH3CN or toluene produced all-trans isomers, crystallization
from a mixture of acetonitrile and n-hexane yielded essentially
the trans–cis isomer. The presence of CH3CN in molecular packing
of trans–cis isomers might be an important packing factor govern-
ing the orientation of the ligands, resulting in different supramo-
lecular structures. In the all-trans configurated diorganotins, the
Sn–O distance is shorter and the Sn–Cl distance is longer. Compa-
[22] B. Coupez, C. Boehme, G. Wipff, Phys. Chem. Chem. Phys. 4 (2002) 5716.
[23] K. Gholivand, N. Oroujzadeh, F. Afshar, J. Organomet. Chem. 695 (2010) 1383.
[24] K. Gholivand, Z. Shariatinia, J. Organomet. Chem. 691 (2006) 4215.
[25] K. Gholivand, Z. Shariatinia, M. Pourayoubi, Polyhedron 25 (2006) 711.

K. Gholivand, S. Farshadian / Inorganica Chimica Acta 368 (2011) 111–123
123
[26] R.N. Kapoor, P. Guillory, L. Schulte, F. Cervantes-Lee, I. Haiduc, L. Parkanyi, K.H.
Pannell, Appl. Organomet. Chem. 19 (2005) 510.
[41] D.E.C. Corbridge, Phosphorus an Outline of its Chemistry Biochemistry and
Technology, fifth ed., Elsevier, Amsterdam, 1995.
[27] V.G. Kumar Das, Y.C. Keong, C. Wei, P.J. Smith, T.C.W. Mak, J. Chem. Soc., Dalton
Trans. (1987) 129.
[28] K. Gholivand, F. Mojahed, Z. Anorg. Allg. Chem. 632 (2006) 1570.
[29] For 2a: Bruker, SAINTPLUS, v. 6.01, Data Reduction and Correction Program,
Bruker AXS, Madison, Wisconsin, USA, 1998.
[42] D.G. Gilheany, Chem. Rev. 94 (1994) 1339.
[43] K. Gholivand, A.M. Alizadehgan, F. Mojahed, P. Soleimani, Polyhedron 27
(2008) 1639.
[44] K. Gholivand, Z. Shariatinia, M. Pourayoubi, Z. Anorg. Allg. Chem. 632 (2006)
160.
[30] For 2a: Bruker, SMART, v.5.059, Bruker Molecular Analysis Research Tool, Bruker
AXS, Madison, Wisconsin, USA, 1998.
[45] P.C. Srivastava, S. Bajpai, Sm. Bajpai, R. Kumar, R.J. Butcher, Inorg. Chim. Acta
358 (2005) 227.
[31] For 1b, 1bꢀCH3CN and 4b: Bruker APEX2 Software Package, Bruker AXS Inc.,
[46] J.S. Casas, A. Castineriros, E.G. Martines, A.S. Gonzales, A. Sanches, J. Sordo,
Polyhedron 16 (1997) 795.
5465, East Cheryl Parkway, Madison, WI, 2005, p. 5317.
[32] For 2bꢀCH3CN, 3b: Bruker, Programs APEX II, version 2.0-1; SAINT, version 7.23A;
SADABS, version 2004/1; XPREP, version 2005/2; SHELXTL, version 6.1. Bruker AXS
Inc., Madison, WI, USA, 2005.
[47] M. Hill, M.F. Mahon, K.C. Molloy, J. Chem. Soc., Dalton Trans. (1996) 1857.
[48] S. Bhandari, M.F. Mahon, K.C. Molloy, J. Chem. Soc., Dalton Trans. (1999) 1951.
[49] N.W. Alcock, J.F. Sawyer, J. Chem. Soc., Dalton Trans. (1977) 1090.
[50] R. Altmann, K. Jurkschat, M. Schürmann, D. Dakternieks, A. Duthie,
Organometallics 17 (1998) 5858.
[51] S.E. Denmark, X. Su, Tetrahedron 55 (1999) 8727.
[52] R. Zhang, G. Tian, C. Ma, J. Organomet. Chem. 690 (2005) 4049.
[53] A.K. Tewari, R. Dubey, ARKIVOC (x) (2009) 283.
[33] For 2a, 3b: G.M. Sheldrick, SADABS, v. 2.01, Bruker/Siemens Area Detector
Absorption Correction Program, Bruker AXS, Madison, Wisconsin, USA, 1998.
[34] For 2a, 3b: G.M. Sheldrick, SHELXTL, v. 5.10, Structure Determination Software
Suit, Bruker AXS, Madison, WI, USA, 1998.
[35] For 1b, 1bꢀCH3CN, 4b: G.M. Sheldrick, SHELXTL, v. 5.10, Structure Determination
Software Suit, Bruker AXS, Madison, WI, USA, 1998.
[54] K. Gholivand, H.R. Mahzouni, M. Pourayoubi, S. Amiri, Inorg. Chim. Acta 363
(2010) 2318.
[36] For 2bꢀCH3CN: G.M. Sheldrick, Programs SHELXS97 (Crystal Structure Solution)
and SHELXL97 (Crystal Structure Refinement), University of Gottingen, Germany,
1997.
[37] R. Murugavel, R. Pothiraja, S. Shanmugan, N. Singh, R.J. Butcher, J. Organomet.
Chem. 692 (2007) 1920.
[38] K. Gholivand, S. Farshadian, Z. Hosseini, K. Khajeh, N. Akbari, Appl. Organomet.
Chem. 24 (2010) 700.
[39] M.A.M.K. Sanhoury, M.T. Ben Dhia, M. Nsangou, M.R. Khaddar, Polyhedron 25
(2006) 1373.
[55] F.H. Allen, S.A. Bellard, M.D. Brice, B.A. Cartwright, A. Doubleday, H. Higgs, T.
Hummelink, B.G. Hummelink-Peters, O. Kennard, W.D.S. Motherwell, J.R.
Rogers, D.G. Watson, Acta Crystallogr., Sect. B 35 (1979) 2331.
[56] A.R. Narga, M. Schuermann, C. Silvestru, J. Organomet. Chem. 623 (2001)
161.
[57] P.J. Smith (Ed.), Chemistry of Tin, second ed., Blackie, London, 1998.
[58] A. Bondi, J. Phys. Chem. 68 (1964) 441.
[59] K. Jurkschat, F. Hesselbarth, M. Dargatz, J. Lehmann, E. Kleinpeter, A. Tzschach,
J. Meunier-Piret, J. Organomet. Chem. 388 (1990) 259.
ˇ
ˇ
ˇ
[40] J. Holecek, M. Nádvorník, K. Handlír, A. Lycka, J. Organomet. Chem. 315 (1986)
299.