Synthesis and characterization of organophosphine/phosphite stabilized N-silver(I) succinimide: crystal structure of [(Ph3P)3 · AgNC4H4O2]

Article abstract of DOI:10.1016/j.poly.2009.02.021

Six organophosphine/phosphite stabilized N-silver(I) succinimide complexes of the type L_n · AgNC₄H₄O₂ (L = PPh₃; n = 1, 2a; n = 2, 2b; n = 3, 2c; L = P(OEt)₃; n = 1, 2d; n = 2, 2e; n = 3, 2

Full text of DOI:10.1016/j.poly.2009.02.021

Polyhedron 28 (2009) 1191–1195
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Polyhedron
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Synthesis and characterization of organophosphine/phosphite stabilized
N-silver(I) succinimide: crystal structure of [(Ph3P)3 ꢀ AgNC4H4O2]
*
Xian Tao, Yue-Qin Li, Hui-Hua Xu, Ning Wang, Fang-Li Du, Ying-Zhong Shen
Applied Chemistry Department, School of Material Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, PR China
a r t i c l e i n f o
a b s t r a c t
Article history:
Six organophosphine/phosphite stabilized N-silver(I) succinimide complexes of the type Ln ꢀ AgNC4H4O2
(L = PPh3; n = 1, 2a; n = 2, 2b; n = 3, 2c; L = P(OEt)3; n = 1, 2d; n = 2, 2e; n = 3, 2f) have been prepared by
reacting [AgNC4H4O2], which can be synthesized from succinimide and excessive Ag2O in boiling water,
with triphenylphosphine or triethylphosphite in dichloromethane under a nitrogen atmosphere. These
complexes were obtained in high yields and characterized by elemental analysis, 1H, 13C{H} NMR, IR
spectroscopy and thermal analysis (TG and DSC). The molecular structure of 2c has been determined
by X-ray single crystal analysis, in which the silver atom is in a distorted tetrahedral geometry.
Ó 2009 Elsevier Ltd. All rights reserved.
Received 20 October 2008
Accepted 4 February 2009
Available online 3 March 2009
Keywords:
N-silver(I) succinimide
Organophosphine
Phosphite
Crystal structure
1. Introduction
[23–28]. The experiment shows that the organophosphine stabi-
lized silver(I) carboxylates were thermally stable, and decomposed
Silver(I) complexes have been widely studied due to their rich
structural information [1–6], potential applications in catalysis
[7] and material science [8,9]. Recently renewed interest has been
paid to Lewis-base stabilized silver(I) complexes, mostly because
of their application as precursors in the growth of silver thin films
via chemical vapor deposition (CVD) techniques, which could be
used as an interconnector for future generation of deep submicron
integrated circuits due to lower resistivity and superior electromi-
gration resistance [10].
OrganoMetallic Chemical Vapor Deposition (OMCVD) is a very
effective technique for the growth of high quality metal films,
because of its high deposition rates with good step coverage [11–
14] and the high aspect ratio in the multilevel metallization struc-
ture [15]. Precursors for CVD should have: (i) good volatility during
the evaporation and transportation in the gas phase; (ii) high pur-
ity and a suitable thermal decomposition mechanism; (iii) suitable
thermal stability which means that it cannot decompose during
the transportation but will decompose easily in the CVD reactor
[16,17]. Out of this, the development of a new generation of
silver(I) complexes as precursors has had an enormous impact.
The silver precursors most often used in CVD are organometallic
or b-diketonate complexes with tertiary phosphines (PMe3, PEt3)
[18,19], alkenes or [20] alkynes [21,22] as ancillary ligands and
Lewis-base stabilized silver(I) carboxylates [23–30]. Of the latter
ones, volatile perfluorinated and aliphatic Ag(I) carboxylates and
their complexes with tertiary phosphines have been reported
to silver over a wide temperature range and with an interesting
decomposition mechanism [29]. The properties of silver(I) com-
plexes having Ag–O [24–26,30–32], Ag–X [21,25] or Ag–C [21,28]
bonds have been investigated frequently, whilst silver(I) com-
plexes having Ag–N bonds have rarely been reported. To the best
of our knowledge, Lewis-base stabilized N-silver(I) succinimide
complexes have not been reported. In order to search for a new
kind of silver complex to be used as a precursor for the CVD tech-
nique, herein we describe the synthesis and characterization of a
series of organophosphine/phosphite stabilized N-silver(I) succini-
mide complexes, [Ln ꢀ AgNC4H4O2] (L = PPh3, n = 1, 2a; n = 2, 2b;
n = 3, 2c; L = P(OEt)3; n = 1, 2d; n = 2, 2e; n = 3, 2f). The single crys-
tal structure of 2c has been determined and is discussed as well in
this paper.
2. Experimental
2.1. General procedures
All operations were carried out under an atmosphere of purified
nitrogen with standard Schlenk techniques. The solvent dichloro-
methane (CH2Cl2) was purified by distillation from P2O5 under N2
before use. The N-silver(I) succinimide was synthesized by succin-
imide with excessive Ag2O in boiling water. 1H NMR were recorded
on a Bruker Avance 300 spectrometer operating at 300.130 MHz in
the Fourier transform mode; 13C{H} NMR spectra were recorded at
75.467 MHz. Chemical shifts are reported in d units (parts per mil-
lion) downfield from tetramethylsilane (d = 0.0 ppm) with the sol-
vent as the reference signal (1H NMR, CDCl3 d = 7.26; 13C{H} NMR,
* Corresponding author. Tel.: +86 25 52112903 84765; fax: +86 25 52112626.
E-mail address: yz_shen@nuaa.edu.cn (Y.-Z. Shen).
0277-5387/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.poly.2009.02.021

1192
X. Tao et al. / Polyhedron 28 (2009) 1191–1195
CDCl3 d = 77.55). Infrared spectra were collected on Bruker Vector
22 in KBr at room temperature. Elemental analysis was performed
on a Perkin–Elmer 240 C elemental analyzer. ThermoGravimetric
(TG) and Differential Scanning Calorimetric (DSC) studies were car-
ried out with a NETZSCH STA 449 C with a constant heating rate of
10 °C minꢁ1 under Argon (1.0 cm3 minꢁ1). Melting points were ob-
served in sealed capillaries and are uncorrected.
C6H5), 133.8 (JPC = 8.6 Hz, C6H5), 129.6 (C6H5), 128.6 (JPC = 8.8 Hz,
C6H5). IR (KBr) data (cmꢁ1): 3047 (m), 1703 (m), 1598 (s), 1477
(m), 1434 (s), 1344 (s), 1282 (s), 1245 (s), 1157 (m), 1096 (s),
1026 (m), 998 (m), 806 (m), 743 (s), 694 (s), 513 (s), 465 (m).
2.2.5. Synthesis of (EtO)3P ꢀ AgNC4H4O2 (2d)
Complex 2d can be synthesized by a similar procedure used for
the synthesis of 2a (Section 2.2.1). In this respect, [(EtO)3P] (1.87 g,
11.27 mmol) was reacted with N-silver(I) succinimide (2.32 g,
11.27 mmol). After appropriate work-up, complex 2d was isolated
as a white solid. Yield: 3.81 g (91% based on N-silver(I) succini-
mide). Mp.: 53–54 °C. Anal. Calc. for C10H19O5AgPN: C, 32.28; H,
5.15. Found: C, 32.16; H, 5.02%. 1H NMR (CDCl3): d 1.3 (t, 9H,
CH3/CH3CH2–, JHH = 7.0 Hz), d 2.6 (s, 4H, CH2–H), 4.0 (m, 6 H,
CH2/CH3CH2–). 13C{H} NMR (CDCl3): d 31.9 (CH2), d 191.0 (C),
16.1 (JPC = 6.7 Hz, CH3/CH3CH2–), 61.3 (JPC = 3.8 Hz, CH2/CH3CH2–).
IR (KBr) data (cmꢁ1): 3437 (m), 2981 (m), 2926 (m), 1701 (m),
1613 (s), 1441 (m), 1358 (s), 1296 (s), 1248 (s), 1163 (s), 1021
(s), 935 (s), 774, (s), 669 (s), 535 (s), 475 (m).
2.2. Synthesis
2.2.1. Synthesis of AgNC4H4O2 (1)
Silver oxide (5.0 g, 22 mmol) was added in one portion to a boil-
ing solution of succinimide (3.8 g, 38 mmol) in 100 ml water. The
reaction vessel was wrapped with aluminum foil in order to ex-
clude as much light as possible. After the stirred solution was
heated to reflux for 45 min and the silver oxide disappeared, the
suspension was filtered through a heated Büchner funnel into a fil-
ter flask, also wrapped with aluminum foil. The filtrate was al-
lowed to stand at room temperature overnight, during which
time N-silver(I) succinimide crystallized. The N-silver(I) succini-
mide was separated on a Büchner funnel, dried in a vacuum oven
for 1 h at 110 °C. The product was stored under nitrogen and kept
in dark place. Yield: 3.1 g (40%, based on Ag2O) [33].
2.2.6. Synthesis of [(EtO)3P]2 ꢀ AgNC4H4O2 (2e)
Complex 2e can be synthesized in the same manner as 2a (Sec-
tion 2.2.2). In this respect, [(EtO)3P] (1.4044 g, 8.46 mmol) was re-
acted with N-silver(I) succinimide (0.8708 g, 4.23 mmol). After
appropriate work-up (see Section 2.2.1) complex 2e was obtained
as a colorless liquid. Yield: 2.09 g (92% based on N-silver(I) succin-
imide). Anal. Calc. for C16H34O8AgNP2: C, 35.70; H, 6.37. Found: C,
35.57; H, 6.38. 1H NMR (CDCl3): d 1.2 (t, 18 H, CH3/CH3CH2–, JHH
= 7.0 Hz), d 2.5 (s, 4 H, CH2–H), 3.9 (m, 12 H, CH2/CH3CH2–).
13C{H} NMR (CDCl3): d 31.8 (CH2), d 191.0 (C), 16.1 (JPC = 6.1 Hz,
CH3/CH3CH2–), 60.0 (JPC = 5.7 Hz, CH2/CH3CH2–). IR (KBr) data
(cmꢁ1): 3440 (m), 2979 (s), 2934 (m), 2901 (m), 2358 (w), 1715
(m), 1612 (s), 1477 (m), 1441 (m), 1391 (s), 1348 (s), 1287 (s),
1245 (s), 1162 (m), 1097 (m), 1022 (s), 937 (s), 771 (s), 669 (m),
536 (s), 442 (m).
2.2.2. Synthesis of Ph3P ꢀ AgNC4H4O2 (2a)
Triphenylphosphine (0.1318 g, 0.5 mmol) dissolved in 20 mL of
CH2Cl2 was added dropwise into a stirred solution of N-silver(I)
succinimide (0.1029 g, 0.5 mmol) suspended in 20 mL of CH2Cl2
at 0 °C. A clear solution was obtained by filtration through a pad
of celite after stirring the reaction mixture for 6 h at 0 °C. A white
solid product was obtained after removing all the volatiles with an
oil-pump vacuum, yield: 0.22 g (94% based on N-silver(I) succini-
mide). Mp.: 182–183 °C dec. Anal. Calc. for C22H19O2AgPN: C,
56.43; H, 4.09. Found: C, 56.36; H, 4.04%. 1H NMR (CDCl3): d 2.7
(s, 4 H, CH2–H), 7.4–7.6 (m, 15 H, Ph-H). 13C{H} NMR (CDCl3): d
32.1 (CH2), d 191.4 (C), 134.0 (JPC = 16.0 Hz, C6H5), 131.3 (C6H5),
129.9 (C6H5), 129.2 (JPC = 10.9 Hz, C6H5). IR (KBr) data (cmꢁ1):
3049 (m), 2963 (m), 1709 (m), 1611 (s), 1436 (s), 1348 (s), 1282
(s), 1157 (m), 1096 (s), 1026 (m), 806 (m), 745 (s), 693 (s), 507
(s), 451 (m).
2.2.7. Synthesis of [(EtO)3P]3 ꢀ AgNC4H4O2 (2f)
Complex 2f was synthesized in a similar procedure to that used
for the synthesis of 2a (Section 2.2.1). In this respect, [(EtO)3P]
(1.5538 g, 9.36 mmol) was reacted with N-silver(I) succinimide
(0.6423 g, 3.12 mmol). After appropriate work-up, complex 2d
was isolated as a colorless liquid. Yield: 2.03 g (92% based on N-sil-
ver(I) succinimide). Anal. Calc. for C22H49O11AgP3N: C, 37.51; H,
7.01. Found: C, 37.32; H, 6.89%. 1H NMR (CDCl3): d 1.3 (t, 27H,
CH3/CH3CH2–, JHH = 7.0 Hz), d 2.6 (s, 4 H, CH2–H), 4.0 (m, 18 H,
CH2/CH3CH2–). 13C{H} NMR (CDCl3): d 32.1 (CH2), d 191.5 (C),
16.2 (JPC = 5.9 Hz, CH3/CH3CH2–), 59.5 (JPC = 6.6 Hz, CH2/CH3CH2–).
IR (KBr) data (cmꢁ1): 3414 (m), 2979 (s), 2926 (m), 2898 (m),
1701 (m), 1598 (s), 1437 (m), 1441 (w), 1391 (m), 1348 (s), 1295
(s), 1252 (s), 1162 (m), 1097 (m), 1023 (s), 933 (s), 773, (s), 669
(m), 556 (m), 454 (m).
2.2.3. Synthesis of (Ph3P)2 ꢀ AgNC4H4O2 (2b)
Complex 2b was obtained by following the above procedure,
only using N-silver(I) succinimide (0.1379 g, 0.67 mmol) and tri-
phenylphosphine (0.3515 g, 1.34 mmol) instead. Yield: 0.47 g
(96% based on N-silver(I) succinimide). Mp.: 196–197 °C. Anal. Calc.
for C40H34O2AgP2N: C, 65.77; H, 4.69. Found: C, 65.63; H, 4.63%. 1H
NMR (CDCl3): d 2.6 (s, 4 H, CH2–H), 7.3–7.5 (m, 30 H, Ph-H). 13C{H}
NMR (CDCl3): d 32.5 (CH2), d 192.4 (C), 133.9 (JPC = 16.8 Hz, C6H5),
132.6 (JPC = 24.1 Hz, C6H5), 130.0 (C6H5), 128.7 (JPC = 9.5 Hz, C6H5).
IR (KBr) data (cmꢁ1): 3655 (m), 3049 (m), 2962 (m), 2361 (w),
1700 (m), 1603 (s), 1583 (m), 1478 (m), 1434 (s), 1345 (s), 1285
(s), 1247 (s), 1183 (w), 1095 (s), 1026 (m), 996 (m), 803 (m), 746
(s), 695 (s), 512 (s), 436 (m).
2.3. Single crystal structure of (Ph3P)3 ꢀ AgNC4H4O2 (2c)
Single crystals of 2c could be obtained by cooling a saturated
dichloromethane solution to ꢁ20 °C. Suitable crystals for X-ray
determination were placed in glue under N2 due to their sensitive
nature to oxygen and moisture. The X-ray structure measurement
was performed on a BRUKER SMART Apex CCD, detector equipped
2.2.4. Synthesis of (Ph3P)3 ꢀ AgNC4H4O2 (2c)
Complex 2c can be synthesized in the same manner as 2a (Sec-
tion 2.2.2). In this respect, triphenylphosphine (0.4328 g,
1.65 mmol) was reacted with N-silver(I) succinimide (0.1132 g,
0.55 mmol). After appropriate work-up (see Section 2.2.1), com-
plex 2c was obtained as a white solid. Yield: 0.51 g (93% base on
N-silver(I) succinimide). Mp.: 194–196 °C dec. Anal. Calc. for
C58H49AgO2P3N: C, 70.17; H, 4.98. Found: C, 69.91; H, 4.73%. 1H
NMR (CDCl3): d 2.5 (s, 4 H, CH2–H), 7.3–7.5 (m, 45 H, Ph-H).
13C{H} NMR (CDCl3): d 32.5 (CH2), d 192.5 (C), 134.0 (JPC = 4.8 Hz,
with graphite monochromatic Mo Ka radiation (k = 0.71073 Å), at
room temperature. The program SMART [34] was used for determi-
nation of the unit cell. Data reduction and integration was carried
out with SAINT [34] and absorption corrections were applied using
the program SADABS [35]. The structure was solved using direct
methods and refined by full-matrix least-squares procedures on

X. Tao et al. / Polyhedron 28 (2009) 1191–1195
1193
Table 1
in polar or unsaturated hydrocarbons such as methylenechloride,
benzene and tetrahydrofuran. All the products obtained gave satis-
factory elemental analysis results and were characterized by FT-IR,
1H NMR and 13C {H} NMR spectroscopy.
Crystallographic data and analysis parameters for (Ph3P)3 ꢀ AgNC4H4O2 ꢀ 3CH2Cl2.
Formula
C58H49AgNO2P3 ꢀ 3(CH2Cl2)
Formula weight
Space group
Crystal size (mm)
Crystal system
Z value
a (Å)
b (Å)
c (Å)
1247.54
ꢀ
The spectra of succinimide were investigated by Woldbaek, Kla-
eboe and Christensen [38]. Assignments are proposed by compar-
ison with the normal-coordinate interpretation presented by the
authors mentioned above. So far, discussion of the IR spectra of
the metal complexes has been restricted to the stretching carbonyl
band (1700 cmꢁ1) [39].
P1
0.6 ꢃ 0.5 ꢃ 0.4
triclinic
2
13.070(3)
13.496(3)
20.073(4)
94.283(4)
105.502(4)
116.693(3)
1.395
In the IR spectra, the broad N–H stretching band (ꢂ3170 cmꢁ1
)
a
(°)
b (°)
(°)
in succinimide disappears in the complexes obtained, as well as the
sharp band at 820 cmꢁ1 assigned to the out-of-plane N–H bending
mode [38]. The in-plane N–H bending vibration has been tenta-
tively associated with a sharp peak at 1418 cmꢁ1 in succinimide,
with an overtone at ꢂ2800 cmꢁ1. The overtone is absent from
the spectra of the complexes. This illustrates the formation of a
Ag–N bond.
c
Dcalc [g/cm3]
Index ranges
Crystal shape/color
F(000)
ꢁ15 6 h 6 15, ꢁ16 6 k 6 10, ꢁ23 6 l 6 20
block/colorless
1276
l
(Mo K
a
) (mmꢁ1
)
0.73
0
k (Mo K
Temperature (K)
h Range (°)
a) (AÅ)
0.71073
295(2)
1.9–25.0
10274
0.066
0.160
1.18
1.10
In the 1600–1800 cmꢁ1 region, succinimide contains sharp
peaks at 1773 and 1695 cmꢁ1 for the in-phase and out-of-phase
stretching motions of the C@O groups [38]. In the N-silver(I) suc-
cinimide complexes, these bands are found at 1700–1710 and
1580–1615 cmꢁ1, respectively. These changes, which are corre-
lated with those found for the uracil moiety [38], could be ascribed
to the delocalization of the anionic charge to the ring and carbonyl
groups, thus decreasing the C@O bond order (Scheme 2). The
(C@O) region is very sensitive to proton substitution, but rather
insensitive to whether the C@O groups are involved in metal coor-
dination [38]. A weak band at 420 cmꢁ1, believed to involve the
C@O in-plane bending vibration, was shifted to 436–475 cmꢁ1 in
the complexes. However, the weakness of these bands in the infra-
red spectra complicates their use for diagnostic purposes.
The NMR spectra (1H and 13C{H}) were recorded for all six com-
plexes (see Section 2) at room temperature, The 1H NMR spectra
are consistent with the stoichiometries of the complexes. The pro-
tons of complexes 2a–2c in the aryl proton region were in the
range 7.2–7.6 ppm. The complexes (2d–2f) are easily distinguished
because the resonances of the protons show only two groups. The
proton of –CH2– in C4H4NO2– appeared at 2.5–2.7 ppm, which
agrees well with that previously reported [40]. In the 13C{H}
NMR spectra, the triphenylphosphine carbon resonances of 2a–2c
are easily distinguished (128.6–134.1 ppm) from the resonance of
–CH2– on C4H4NO2– (31.8–32.1 ppm).
Independent reflections [(I) > 2
R1 [I > 2
(h)]a
(h)]b
r(I)]
r
r
wR2 [I>2
Goodness-of-fit (GOF) on F2c
0
D
D
qmax (e ÅAꢁ3
)
0
qmin (e ÅAꢁ3
)
ꢁ0.78
P
P
P
P
aR1
=
(||Fo| ꢁ |Fc||)/ |Fo|; wR2 = [ (w(F2o ꢁ Fc2)2)/ (wFo4)]1/2
.
bw = 1/[
r
2(F2o) + (0.064P)2], P = (Fo2 + 2F2c )/3.
P
cS = [ w(F2o ꢁ F2c )2]/(n ꢁ p)1/2, n = number of reflections, p = parameters used.
F2 (SHELX-97) [36]. All of the non-hydrogen atoms were refined
with anisotropic displacement parameters. Crystallographic data
and details on refinement are presented in Table 1. The crystal
structure of 2c is drawn using ORTEP [37].
3. Results and discussion
3.1. Synthesis
The phosphine/phosphite stabilized N-silver(I) succinimide
complexes of the type [Ln ꢀ AgNC4H4O2] (L = PPh3, n = 1, 2a; n = 2,
2b; n = 3, 2c; L = P(OEt)3; n = 1, 2d; n = 2, 2e; n = 3, 2f) were pre-
pared by reacting Ph3P/(EtO)3P with N-silver(I) succinimide in
dichloromethane in stoichiometric amounts at 0 °C in high yield
(Scheme 1). The complexes were isolated as white solids (2a–2c)
or colorless liquids (2d–2f). They are very sensitive to moisture,
oxygen as well as light. The complexes are insoluble in cold non-
polar solvents such as petroleum, whereas they are highly soluble
3.2. Single crystal structure of 2c
Single crystals of [(Ph3P)3 ꢀ AgNC4H4O2] (2c) could be grown by
slowly cooling a saturated dichloromethane solution containing 2c
to ꢁ20 °C. The molecular structure of 2c is depicted in Fig. 1. Se-
0
lected bond distances (AÅ) and bond angles (°) are given in Table 2.
ꢀ
Complex 2c crystallizes in the triclinic space group P1, and is
O
O
composed of one molecule of [(Ph3P)3 ꢀ AgNC4H4O2] and three mol-
ecules of dichloromethane (Fig. 1). In the complex, a four-coordi-
nated silver(I) ion is present with three PPh3 ligands occupying
three of the coordination sites (PPP) and the nitrogen atom of suc-
cinimide occupying the fourth site, forming a distorted tetrahedral
geometry around silver. The N–Ag–P(1) (107.29(1)°) and N–Ag–
P(3) (94.95(1)°) angles are smaller than that of the ideal tetrahe-
dral angle, while the P(1)–Ag–P(2) (113.70(5)°) and P(2)–Ag–P(3)
(113.32(5)°) angles are larger (Table 2).
The succinimide ring is roughly planar; the N atom is 0.027 Å
above the C(55)–C(56)–C(57)–C(58) plane, producing a slight
‘‘envelope” distortion in the ring. The succinimide ring is similar
to the reported complex [Li(Ag(Suc)2) ꢀ H2O] [38]. The carbonyl
oxygen, however, show different distances to the plane, implying
the no coordinating interactions with silver.
CH2Cl2
N
Ag
nL
N
AgLn
+
O
O
2a-2f
1
n = 1 (2a)
n = 2 (2b)
n = 3 (2c)
L = PPh3;
L=P(OEt)3;
n = 1 (2d)
n = 2 (2e)
n = 3 (2f)
Scheme 1. Synthesis of complexes 2a–2f.

1194
X. Tao et al. / Polyhedron 28 (2009) 1191–1195
O
O
O
C
C
C
C
C
H2C
H2C
H2C
CH 2
H2C
N
AgLn
N
AgLn
N
AgLn
H2C
C
O
O
O
Scheme 2. Delocalization of the anionic charge into the ring and carbonyl groups, decreasing the C@O bond order.
Table 2
Selected bond lengths (Å) and bond angles (°) for the (Ph3P)3 ꢀ AgNC4H4O2 ꢀ 3CH2Cl2.
Bond lengths (Å)
Ag(1)–P(1)
Ag(1)–P(3)
N(1)–C(55)
O(1)–C(55)
C(55)–C(56)
C(57)–C(58)
P(1)–C(7)
2.619(2)
2.575(2)
1.342(7)
1.216(7)
1.524(8)
1.511(9)
1.824(6)
1.818(6)
1.830(5)
1.823(5)
Ag(1)–P(2)
Ag(1)–N(1)
N(1)–C(58)
O(2)–C(58)
C(57)–C(56)
P(1)–C(1)
P(1)–C(13)
P(2)–C(31)
P(3)–C(37)
P(3)–C(43)
2.561(1)
2.313(4)
1.354(8)
1.205(7)
1.490(9)
1.830(5)
1.831(5)
1.821(6)
1.820(5)
1.824(6)
P(2)–C(19)
P(2)–C(25)
P(3)–C(49)
Bond angles (°)
N(1)–Ag(1)–P(2)
N(1)–Ag(1)–P(3)
P(2)–Ag(1)–P(3)
N(1)–Ag(1)–P(1)
P(2)–Ag(1)–P(1)
P(3)–Ag(1)–P(1)
C(7)–P(1)–C(1)
C(7)–P(1)–C(13)
C(7)–P(1)–Ag(1)
C(1)–P(1)–Ag(1)
C(13)–P(1)–Ag(1)
C(19)–P(2)–C(31)
C(19)–P(2)–C(25)
C(19)–P(2)–Ag(1)
C(31)–P(2)–Ag(1)
C(25)–P(2)–Ag(1)
C(37)–P(3)–C(49)
C(37)–P(3)–C(43)
C(37)–P(3)–Ag(1)
C(49)–P(3)–Ag(1)
C(56)–C(57)–C(58)
C(55)–N(1)–C(58)
116.5(1)
94.9(1)
C(32)–C(31)–P(2)
C(36)–C(31)–P(2)
C(38)–C(37)–P(3)
C(42)–C(37)–P(3)
C(44)–C(43)–P(3)
C(48)–C(43)–P(3)
O(1)–C(55)–N(1)
O(1)–C(55)–C(56)
N(1)–C(55)–C(56)
C(57)–C(56)–C(55)
C(8)–C(7)–P(1)
C(20)–C(19)–P(2)
C(24)–C(19)–P(2)
C(55)–N(1)–Ag(1)
C(58)–N(1)–Ag(1)
C(6)–C(1)–P(1)
119.7(5)
121.7(5)
118.0(4)
123.0(4)
124.1(5)
116.6(5)
126.1(6)
122.6(6)
111.2(6)
103.8(5)
118.2(4)
119.0(4)
123.3(5)
123.5(4)
124.1(4)
122.6(4)
117.7(4)
124.1(4)
125.6(6)
122.6(7)
111.9(6)
120.6(2)
113.3(5)
107.3(1)
113.7(5)
109.5(5)
102.8(2)
101.9(2)
113.9(2)
116.9(2)
117.7(2)
103.3(3)
102.8(2)
115.2(2)
121.1(2)
111.1(2)
102.6(2)
103.0(3)
114.7(2)
111.7(2)
103.4(6)
109.6(5)
Fig. 1. ORTEP drawing of 2c, showing 30% probability displacement ellipsoids. The
hydrogen atoms and solvent molecules are omitted for clarity.
C(2)–C(1)–P(1)
C(12)–C(7)–P(1)
O(2)–C(58)–N(1)
O(2)–C(58)–C(57)
N(1)–C(58)–C(57)
C(43)–P(3)–Ag(1)
The C–N–C and N–C–C angles, depending on the substituent on
nitrogen, are roughly correlated with the electrophilic character of
the substituent. For instance, the C–N–C angle progressively
decreases with decreasing substituent electrophilic character
(115.0(15)°, C1; 111.6(7)°, Br; 112.6(6)°, H; 109.6(5)°, Ag;
108.3(4)°, Ni), whereas the adjacent N–C–C angles increase, but
to a lesser extent (106.5(15)°, C1; 107.4(8)°, Br; 108.3(6)°, H;
111.9(6)°, Ag; 112.1(5)°, Ni) [38].
The Ag–P distances [2.619(2), 2.561(1), 2.575(2) Å] are longer
than the sum of covalent radii of the P and Ag atoms (2.44 Å)
[40] and that of [(R3P)2AgPI] (PI = C8H4NO2) [2.4944(7) Å] [41].
The Ag–N distance [2.313(4) Å] is much longer than that of
[(R3P)2AgPI] (PI = C8H4NO2) [2.223(3) Å] [41] and the angles of P–
Ag–P [113.70(5)° and 109.46(5)°] are much smaller than that of
[(Ph3P)2AgPAZ] [130.88(5)° and 125.49(8)°] (PAZ = C8H5N2O) [41].
1.0
100
80
TG
DSC
0.5
0.0
60
-0.5
-1.0
3.3. Thermal analysis
40
The complex was studied by ThemoGravimetry (TG) to obtain
information on transition, decomposition temperatures and fre-
quencies and then by Differential Scanning Calorimetry (DSC) to
determine the change of entropy during thermolysis. These studies
are also required to optimize the temperature at which the respec-
tive single silver precursor should be maintained during the CVD
experiments. For an example, the TG and DSC curves of complex
2d are shown in Fig. 2. It can be seen from the DSC curve that there
100
200
300
C)
400
Temperature (o
Fig. 2. TG and DSC curves of 2d (heating rate 10 °C minꢁ1, argon atmosphere).
is one apparent endothermic process with a peak temperature of
55 °C, which could be attributed to the melting process of complex

X. Tao et al. / Polyhedron 28 (2009) 1191–1195
1195
[10] G.V. Samsonov, Handbook of the Physicochemical Properties of the Elements,
IFI-Plenum, New York, 1968.
[11] A. Jain, K. Chi, T.T. Kodas, M.J. Hampden-Smith, J. Electrochem. Soc. 140 (1993)
1434.
[12] N. Awaya, Y. Arita, in: Proceedings of the 1991 Symposium on VLSI
Thchnology, Orso, Japan, 1991, p. 37.
[13] J.E. Parmeter, G.A. Petersen, P.M. Smith, C.A. Apblett, J.S. Reid, J.A.T. Norman,
A.K. Hochberg, D.A. Roberts, T.R. Omstead, J. Vac. Sci. Technol. B13 (1995)
130.
[14] G. Braeckelmann, D. Manger, A. Burke, G.G. Peterson, A.E. Kaloyeros, C.
Reidsema, T.R. Omstead, J.F. Loan, J.J. Sullivan, J. Vac. Sci. Technol. B14 (1996)
1828.
[15] S. Kim, D.J. Choi, K.R. Yoon, K.H. Kim, S.K. Koh, Thin Solid Films 311 (1997) 218.
[16] J. Rickerby, J.H.G. Steinke, Chem. Rev. 102 (2002) 1525.
[17] H.K. Shin, K.M. Chi, J. Farkas, M.J. Hampden-Smith, T.T. Kodas, E.N. Duesler,
Inorg. Chem. 31 (1992) 424.
2d. There are two continuous exothermic/endothermic processes
from 163 to 210 °C, with peak temperatures of 189 and 207 °C.
As seen from the TG curve, it is very difficult to distinguish from
one step to another and know the sequence of decomposition of
P(OEt)3 and succinimide. The total weight losses are about
65.09%. The final percentage of the residue is 34.91%, which is
higher than the theoretical value of silver (29.01%), which may
be due to the some impurities in the complex. The complex exhib-
its a proper thermal decomposition temperature indicating that it
could be a promising candidate as a precursor for growing silver
films using the chemical vapor deposition technique.
[18] D.B. Beach, F.K. LeGoues, C.K. Hu, Chem. Mater. 2 (1990) 216.
[19] T.L. Alford, J. Li, J.W. Mayer, S.Q. Wang, Thin Solid Films 262 (1995) R7.
[20] P.L. Pai, C.H. Ting, IEEE Electron Dev. Lett. 10 (1989) 423.
[21] T.T. Kodas, M.J. Hampden-Smith, The Chemistry of Metal CVD, VCH, Weinheim,
1994.
4. Supplementary data
CCDC 687312 contains the supplementary crystallographic data
for 2c. These data can be obtained free of charge via http://
www.ccdc.cam.ac.uk/conts/retrieving.html, or from the Cambridge
Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ,
UK; fax: (+44) 1223-336-033; or e-mail: deposit@ccdc.cam.ac.uk.
[22] F.R. Hartley, Chem. Res. 73 (1973) 163.
[23] J. Li, R.S. Blewer, J.W. Mayer, MRS Bull. 18 (1993) 18.
[24] H.K. Shin, M.J. Hampden-Smith, E.N. Duesler, T.T. Kodas, Can. J. Chem. 70
(1992) 2954.
[25] R.J.H. Voorhoeve, J.W. Merewether, J. Electrochem. Soc. 119 (1972) 364.
[26] N.A. Clinton, J.K. Kochi, J. Organomet. Chem. 42 (1972) 229.
[27] D.J. Darensbourg, M.W. Holteamp, B. Khandelwal, J.H. Reibenspies, Inorg.
Chem. 33 (1994) 531.
Acknowledgement
[28] J.K. Kochi, Acc. Chem. Res. 7 (1974) 351.
We gratefully acknowledge the National 863 Research Project
(2006AA03Z219), Natural Science Foundation of Jiangsu province
(BK2007199); The Foundation for ‘‘Liu Da Ren Cai” of Jiangsu Prov-
ince (06-E-021) is also acknowledged.
[29] T. Miyaji, Z. Xi, K. Nakajima, T. Takahashi, Organometallics 20 (2001) 2859.
[30] A. Bayler, A. Schier, H. Schmidbaur, Inorg. Chem. 37 (1998) 4353.
[31] M.B. Dines, Inorg. Chem. 11 (1972) 2949.
[32] B.G. Lor, M. Iglesias, C. Cascales, E.G. Puebla, M.A. Monge, Chem. Mater. 13
(2001) 1364.
[33] H.E. Baumgarten, Organic Synthesis, coll. vol. 5, New York, 1973, p. 663.
[34] Bruker AXS Inc., SAINT, Area Detector Control and Data Integration and
Reduction Software, Madison, WI, USA, 1997.
References
[35] G.M. Sheldrick, SADABS, Program for Empirical Absorption Correction of Area
Detector Data, University of Gottingen, Germany, 1997.
[36] G.M. Sheldrick, SHELX-97, Programs for Crystal Structure Analysis (Release 97-
2), University of Gottingen, Germany, 1997.
[37] L. Zsolnai, G. Huttner, ORTEP, University of Heidelberg, Germany, 1994.
[38] (a) T. Woldbaek, P. Klaeboe, D.H. Christensen, Acta Chem. Scand. Ser. A. A30
(1976) 531;
[1] M. Dennehy, O.V. Quinzani, M. Jennings, J. Mol. Struct. 841 (2007) 110.
[2] I.G. Dance, Polyhedron 5 (1986) 1037.
[3] B. Krebs, G. Henkel, Angew. Chem. Int. Ed. Engl. 30 (1991) 769.
[4] C. Housecroft, Coord. Chem. Rev. 115 (1992) 141.
[5] R.H. Holm, P. Kennepohl, E.I. Solomon, Chem. Rev. 96 (1996) 2239.
[6] M. Hong, W. Su, R. Cao, W. Zhang, W.T. Wong, J. Lu, Inorg. Chem. 38 (1999)
600.
(b) J. Perron, A.L. Beauchamp, Inorg. Chem. 23 (1984) 2853.
[39] D.M. Roundhill, Inorg. Chem. 9 (1970) 254.
[40] B.K. Teo, J.C. Calabrese, Inorg. Chem. 15 (1976) 2467.
[41] D.R. Whitcomb, M. Rajeswaran, J. Chem. Crytallogr. 36 (2006) 587.
[7] F. Colombo, R. Annunziata, M. Benaglia, Tetrahedron Lett. 48 (2007) 2687.
[8] K. Ozawa, F. Iso, Y. Nakao, Z.X. Cheng, H. Fujii, M. Hase, H. Yamaguchi, J. Eur.
Chem. Soc. 27 (2007) 2665.
[9] H. Schmidt, Y. Shen, M. Leschke, Th. Haase, K. Hohse-Hoeinghaus, H. Lang, J.
Organomet. Chem. 669 (2003) 25.