Synthesis, characterization and crystal structures of tri- and tetraphenylantimony(V) compounds containing arylcarbonyloxy moiety

Article abstract of DOI:10.1016/j.jorganchem.2009.07.040

A series of tri- and tetraphenylantimony(V) compounds containing arylcarbonyloxy moiety have been synthesized and characterized by elemental analysis, IR, and NMR spectroscopy. Attempts to grow crystals led to colorless blocks identified by X-ray diffract

Full text of DOI:10.1016/j.jorganchem.2009.07.040

Journal of Organometallic Chemistry 694 (2009) 3708–3717
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Synthesis, characterization and crystal structures
of tri- and tetraphenylantimony(V) compounds
containing arylcarbonyloxy moiety
*
Li Quan, Han-dong Yin , Ji-chun Cui, Min Hong, Da-qi Wang
Department of Chemistry, Liaocheng University, Liaocheng 252059, China
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 16 June 2009
Received in revised form 26 July 2009
Accepted 28 July 2009
Available online 3 August 2009
A series of tri- and tetraphenylantimony(V) compounds containing arylcarbonyloxy moiety have been
synthesized and characterized by elemental analysis, IR, and NMR spectroscopy. Attempts to grow crys-
tals led to colorless blocks identified by X-ray diffraction as (ArCOO)2SbPh3 or (ArCOO)SbPh4.
Ó 2009 Elsevier B.V. All rights reserved.
Keywords:
Tri- and tetraphenylantimony(V)
Arylcarboxylic acid
X-ray diffraction
1. Introduction
1000 CCD diffractometer with graphite monochromated Mo Ka
(k = 0.71073 Å) radiation. 1H and 13C NMR (CDCl3): d spectra were
recorded on Varian Mercury Plus-400 NMR spectrometer and the
chemical shifts were reported in ppm relative to tetramethylsilane
(TMS) in CDCl3.
The chemistry of antimony compounds derived from carboxyl-
ates have been an active area of research for more than eight dec-
ades [1,2], not only for the striking structural possibilities ranging
from discrete monomeric structures to supramolecular assemblies
[3], but also for the biological importance [4] in antimicrobial prop-
erties [5] as well as antitumor activities [6,7]. A great number of
references describing synthesis and biological activities of organ-
oantimony carboxylates with the general formula RnSbX5ꢀn (R = al-
kyl, aryl; n = 3, 4; X = carboxylate) have already appeared in the
literature [8–29]. The published data on the antitumor activity of
these compounds, however, are relatively limited [30,22]. In the
present paper we have prepared a series of arylantimony deriva-
tives of arylcarboxylic acid. We are interested in studying the nat-
ure of bonding and structural information of these compounds. The
general reaction scheme is shown in Scheme 1.
2.2. Syntheses of compounds 1–12
2.2.1. Preparation of Ph3Sb(Cl)(O2C–C9H6N) (1)
2-Quinoline carboxylic acid (0.069 g, 0.4 mmol) and sodium
methoxide (0.4 mmol) were added with stirring to solution con-
taining triphenylantimony dichloride (0.172 g, 0.4 mmol) in tolu-
ene (30 ml). After refluxing for 8 h, the colorless solution was
obtained and then filtered. The solvent was gradually removed
by evaporation under vacuum until the white solid was obtained.
The solid was recrystallized from petroleum ether/dichlorometh-
ane (1:4) to give colorless crystals. Yield 63%, m.p. 129–131 °C.
Anal. Calc. for C28H21NClO2Sb (560.68): C, 59.98; H, 3.77; O, 5.71.
Found: C, 59.72; H, 3.68; O, 5.53%. IR (KBr, cmꢀ1): 1669 (C@O),
1647 (C@N), 1367 (C–O), 593 (Sb–N), 456 (Sb–O), 445 (Sb–C). 1H
NMR (CDCl3): d 7.38 (9H, m, m- and p-Ph), 7.98 (6H, m, o-Ph),
7.55 (1H, d, J = 4 Hz, 10-quinoline-H), 7.83 (1H, d, J = 4 Hz, 7-quin-
oline-H), 9.24 (1H, d, J = 4 Hz, 4-quinoline-H), 8.20 (2H, m, 8,9-
quinoline-H), 8.62 (1H, m, 3-quinoline-H). 13C NMR (CDCl3): d
127.2, 128.3, 134.1, 136.9 (Ph–Sb); 121.5, 127.4, 127.9, 129.1,
129.6, 131.7, 137.1, 148.4, 154.2 (C9H6N); 167.8 (C@O).
2. Experimental
2.1. Materials and instrumentation
Solvents were dried and distilled before use. The elemental
analyses were performed on a PE-2400-II elemental analyzer. IR
spectra were recorded on a Nicolet-460 spectrophotometer, as
KBr discs. X-ray measurements were made on a Bruker Smart-
2.2.2. Preparation of Ph3Sb(O2C–C9H6N)2 (2)
2-Quinoline carboxylic acid (0.072 g, 0.42 mmol) and sodium
methoxide (0.42 mmol) were added with stirring to solution
* Corresponding author. Tel./fax: +86 6358239121.
E-mail addresses: handongyin@lcu.edu.cn, quanli99@126.com (H.-d. Yin).
0022-328X/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2009.07.040

L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
3709
Scheme 1.
containing triphenylantimony dichloride (0.086 g, 0.2 mmol) in
toluene (30 ml). After refluxing for 8 h, the colorless solution was
obtained and then filtered. The solvent was gradually removed
by evaporation under vacuum until the white solid was obtained.
The solid was recrystallized from petroleum ether/dichlorometh-
ane (1:1) to give colorless crystals. Yield 60%, m.p. 130–133 °C.
Anal. Calc. for C38H27N2O4Sb (697.39): C, 65.44; H, 3.90; O, 9.18.
Found: C, 65.21; H, 4.12; O, 9.39%. IR (KBr, cmꢀ1): 1700 (C@O),
1682 (C@N), 1402 (C–O), 478 (Sb–O), 451 (Sb–C). 1H NMR (CDCl3):
d 7.56 (9H, m, m- and p-Ph), 8.13 (6H, m, o-Ph), 7.83 (2H, d, J = 4 Hz,
10-quinoline-H), 8.21 (2H, d, J = 4 Hz, 7-quinoline-H), 9.12 (2H, d,
J = 4 Hz, 4-quinoline-H), 8.34 (4H, m, 8,9-quinoline-H), 8.85 (2H,
m, 3-quinoline-H). 13C NMR (CDCl3): d 129.4, 130.3, 135.6, 139.7
(Ph–Sb); 121.6, 128.7, 129.9, 130.6, 131.3, 132.0, 138.6, 147.9,
153.8 (C9H6N); 170.0 (C@O).
2.2.3. Preparation of Ph4Sb(O2C–C9H6N) (3)
2-Quinoline carboxylic acid (0.076 g, 0.44 mmol) and sodium
methoxide (0.44 mmol) were added with stirring to solution con-
taining teraphenylantimony bromide (0.204 g, 0.4 mmol) in tolu-
ene (30 ml). After refluxing for 8 h, the colorless solution was
obtained and then filtered. The solvent was gradually removed
by evaporation under vacuum until the white solid was obtained.
The solid was recrystallized from petroleum ether/dichlorometh-
ane (1:1) to give colorless crystals. Yield 60%, m.p. 128–132 °C.
Anal. Calc. for C34H26O2NSb (602.33): C, 67.80; H, 4.35; O, 5.31.
Found: C, 67.59; H, 4.59; O, 5.53%. IR (KBr, cmꢀ1): 1678 (C@N),
1660 (C@O), 1345 (C–O), 462 (Sb–O), 450 (Sb–C). 1H NMR (CDCl3):
d 7.45 (12H, m, m- and p-Ph), 8.08 (8H, m, o-Ph), 7.61 (1H, d,
J = 5 Hz, 10-quinoline-H), 7.78 (1H, d, J = 4 Hz, 7-quinoline-H),
9.13 (1H, d, J = 4 Hz, 4-quinoline-H), 8.28 (2H, m, 8,9-quinoline-

3710
L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
H), 8.57 (1H, m, 3-quinoline-H). 13C NMR (CDCl3): d 128.1, 130.7,
133.2, 138.9 (Ph–Sb); 122.3, 127.7, 128.6, 129.5, 131.1, 132.4,
137.1, 149.6, 158.7 (C9H6N); 172.4 (C@O).
(CDCl3): d (100 MHz, CDCl3): 122.10, 125.89, 127.33, 128.05,
128.86, 129.08, 132.23, 137.36, 139.21 (C4H3S, Ph); 174.8 (C@O).
2.2.10. Preparation of Ph3Sb(Cl)[O2C–C6H3(OH)(Br)] (10)
Compound 10 was prepared in the same way as 1. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 73%, m.p. 128–131 °C. Anal. Calc. for
C25H19ClO3BrSb (604.53): C, 49.67; H, 3.17; O, 7.94. Found: C,
49.46; H, 3.35; O, 8.13%. IR (KBr, cmꢀ1): 1697 (C@O), 1395 (C–O),
478 (Sb–O), 452 (Sb–C). 1H NMR (CDCl3): d 7.20–8.68 (18H, m,
Ph); 9.10 (1H, s, Ph–OH). 13C NMR (CDCl3): d 129.1, 132.4, 135.9,
141.1 (C6H5); 129.8, 133.5, 137.8, 140.3, 141.9, 143.0 (C6H3);
175.5 (C@O).
2.2.4. Preparation of Ph3Sb(Cl)[O2C–C6H2Cl3] (4)
Compound 4 was prepared in the same way as 1. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 68%, m.p. 129–132 °C. Anal. Calc. for
C25H17O2Cl4Sb (612.97): C, 48.99; H, 2.80; O, 5.22. Found: C,
48.77; H, 2.98; O, 5.43%. IR (KBr, cmꢀ1): 1710 (C@O), 1455 (C–O),
501 (Sb–O), 478 (Sb–C). 1H NMR (CDCl3): d 7.36–8.83 (m, Ph,
17H). 13C NMR (CDCl3): d 128.8, 133.1, 136.4, 139.7 (C6H5);
129.7, 131.9, 136.2, 140.4, 144.7, 148.2 (C6H3Cl3); 179.6 (C@O).
2.2.5. Preparation of Ph3Sb[O2C–C6H2Cl3]2 (5)
2.2.11. Preparation of Ph3Sb[O2C–C6H3(OH)(Br)]2 (11)
Compound 5 was prepared in the same way as 2. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 65%, m.p. 150–152 °C. Anal. Calc. for
C65H42Cl12O9Sb2 (1635.97): C, 47.72; H, 2.59; O, 8.80. Found: C,
47.41; H, 2.73; O, 9.11%. IR (KBr, cmꢀ1): 1692 (C@O), 1353 (C–O),
471 (Sb–O), 459 (Sb–C). 1H NMR (CDCl3): d 2.12 (3H, s, CH3–O),
4.24 (1H, m, OH), 7.43–8.69 (38H, m, Ph). 13C NMR (CDCl3): d
127.7, 132.6, 135.7, 140.2 (C6H5); 129.7, 132.6, 135.7, 139.8,
142.6, 147.7 (C6H3Cl3); 177.9 (C@O).
Compound 11 was prepared in the same way as 2. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 71%, m.p. 142–144 °C. Anal. Calc. for
C32H23O6Br2Sb (785.08): C, 48.96; H, 2.95; O, 12.23. Found: C,
48.73; H, 3.13; O, 12.41%. IR (KBr, cmꢀ1): 1670 (C@O), 1349 (C–
O), 454 (Sb–O), 443 (Sb–C). 1H NMR (CDCl3): d 7.13–8.41 (21H,
m, Ph); 9.12 (2H, s, Ph–OH). 13C NMR (CDCl3): d 127.6, 130.7,
135.7, 140.9 (C6H5); 129.6, 131.7, 137.7, 139.9, 140.7, 142.3
(C6H3); 170.5 (C@O).
2.2.6. Preparation of Ph4Sb[O2C–C6H2Cl3] (6)
2.2.12. Preparation of Ph4Sb[O2C–C6H3(OH)(Br)] (12)
Compound 6 was prepared in the same way as 3. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 61%, m.p. 131–133 °C. Anal. Calc. for
C31H22O2Cl3Sb (654.62): C, 56.88; H, 3.39; O, 4.89. Found: C,
56.69; H, 3.55; O, 5.01%. IR (KBr, cmꢀ1): 1687 (C@O), 1359 (C–O),
466 (Sb–O), 454 (Sb–C). 1H NMR (CDCl3): d 7.38–8.75 (22H, m,
Ph). 13C NMR (CDCl3): d 127.9, 133.0, 136.2, 142.8 (C6H5); 129.8,
132.4, 136.7, 140.9, 143.5, 149.0 (C6H3Cl3); 182.7 (C@O).
Compound 12 was prepared in the same way as 3. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 66%, m.p. 131–134 °C. Anal. Calc. for
C31H24O3BrSb (646.18): C, 57.62; H, 3.74; O, 7.43. Found: C,
57.41; H, 3.92; O, 7.61%. IR (KBr, cmꢀ1): 1679 (C@O), 1341 (C–O),
458 (Sb–O), 447 (Sb–C). 1H NMR (CDCl3): d 7.14–8.43 (23H, m,
Ph); 9.08 (1H, s, Ph–OH). 13C NMR (CDCl3): d 126.1, 131.2, 134.8,
141.7 (C6H5); 129.9, 132.6, 136.8, 140.9, 142.5, 144.6 (C6H3);
175.9 (C@O).
2.2.7. Preparation of Ph3Sb(Cl)(O2C–C4H3S) (7)
Compound 7 was prepared in the same way as 1. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 80%, m.p. 119–122 °C. Anal. Calc. for
C23H18O2SClSb (515.66): C, 53.57; H, 3.52; O, 6.21; S, 6.22. Found:
C, 53.35; H, 3.73; O, 6.43; S, 6.41%. IR (KBr, cmꢀ1): 1712 (C@O),
1402 (C–O), 489 (Sb–O), 467 (Sb–C). 1H NMR (400 MHz, CDCl3): d
7.23–7.89 (3H, m, C4H3S), 7.25–8.22 (15H, m, C6H5). 13C NMR
(CDCl3): d (100 MHz, CDCl3): 121.6, 126.8, 127.4, 128.1, 128.8,
129.9, 130.7, 135.6, 137.5 (C4H3S, Ph); 175.6 (C@O).
2.3. Crystal structure determination and refinement
Single crystals suitable for X-ray analysis were mounted in a fi-
ber. All measurements were made on a Bruker Smart-1000 CCD
diffractometer
with
graphite
monochromated
Mo
Ka
(k = 0.71073 Å) radiation at 298(2) K using the
U/x
scan technique.
The structures were solved by direct method and different Fou-
rier syntheses using SHELXL-97 program, and refined by full-matrix
least-squares on F2. All non-hydrogen atoms were refined aniso-
tropically. Hydrogen atoms were placed at calculated positions
with C–H distances of 0.93 Å and O–H distances of 0.82 Å riding
on carrier atoms. Crystallographic data and experimental details
of the structure determinations are listed in Table 1.
2.2.8. Preparation of Ph3Sb(O2C–C4H3S)2 (8)
Compound 8 was prepared in the same way as 2. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 87%, m.p. 130–132 °C. Anal. Calc. for
C28H21O4S2Sb (607.35): C, 55.37; H, 3.48; O, 10.53; S, 10.56. Found:
C, 55.12; H, 3.69; O, 10.79; S, 10.80%. IR (KBr, cmꢀ1): 1701 (C@O),
1325 (C–O), 461 (Sb–O), 451 (Sb–C). 1H NMR (400 MHz, CDCl3): d
6.89–7.54 (6H, m, C4H3S), 7.39–8.01 (15H, m, C6H5). 13C NMR
(CDCl3): d (100 MHz, CDCl3): 121.4, 126.5, 127.4, 128.0, 128.9,
129.8, 130.4, 136.4, 138.3 (C4H3S, Ph); 172.3 (C@O).
3. Results and discussion
3.1. IR Spectra
The IR spectra of these compounds have been recorded in the
range of 4000–400 cmꢀ1. The IR spectroscopic data provide fur-
ther support for the molecular constitution of these compounds.
In majority of organoantimony(V) compounds the antimony has
generally a coordination number of five. Because the vacant 5d
orbital of antimony atom can accept lone electron pairs of li-
gands, in some cases the antimony may have a coordination num-
ber of six [8,15] or seven [31,12]. Whereas in compound 1, the
center of antimony atom is mainly considered as three center
four electron bond using p-orbital of antimony rather than d-orbi-
tal contributing to describe the structure. The strong bands at
2.2.9. Preparation of Ph4Sb(O2C–C4H3S) (9)
Compound 9 was prepared in the same way as 3. The solid was
recrystallized from petroleum ether/dichloromethane (1:1) to give
colorless crystals. Yield 87%, m.p. 123–125 °C. Anal. Calc. for
C29H23O2SSb (557.31): C, 62.50; H, 4.16; O, 5.74; S, 2.75. Found:
C, 62.31; H, 4.38; O, 5.96; S, 7.56%. IR (KBr, cmꢀ1): 1694 (C@O),
1331 (C–O), 467 (Sb–O), 456 (Sb–C). 1H NMR (400 MHz, CDCl3): d
6.82–7.70 (3H, m, C4H3S), 7.41–8.12 (20H, m, C6H5). 13C NMR

L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
3711
Table 1
Crystal data and structure refinement details for compounds 1, 5, 6, 8, 11 and 12.
Compound
1
5
6
8
11
12
Empirical formula
Formula weight
T (K)
C28H21ClNO2Sb
560.66
298(2)
C65H42Cl12O9Sb2
1635.89
298(2)
C31H22Cl3O2Sb
654.59
298(2)
C28H21O4S2Sb
607.32
298(2)
C32H23Br2O6Sb
785.07
298(2)
C31H24BrO3Sb
646.16
298(2)
Crystal system
Space group
a (Å)
b (Å)
c (Å)
Monoclinic
P2(1)
Triclinic
P1
Monoclinic
P2(1)/c
Triclinic
P1
Trigonal
P3(2)21
17.4557(19)
17.4557(19)
10.9256(13)
90
90
120
2883.0(6)
3
Monoclinic
P2(1)/n
13.5035(15)
10.9498(12)
18.867(3)
90
106.923(2)
90
2668.9(5)
4
ꢀ
ꢀ
9.1139(12)
9.5042(15)
14.748(2)
90
107.026(2)
90
9.2521(12)
16.616(2)
25.279(3)
73.8670(10)
84.109(2)
84.944(2)
3706.2(8)
2
16.3175(19)
8.9520(9)
20.594(2)
90
112.450(2)
90
9.0024(10)
10.6491(17)
14.4581(18)
68.674(2)
85.459(3)
86.171(3)
1286.0(3)
2
a
(°)
b (°)
c
(°)
V (Å3)
1221.5(3)
2
2780.3(5)
4
Z
F(0 0 0)
560
1.524
1620
1.466
1304
1.564
608
1.568
1152
1.357
1280
1.608
Dcal (g cmꢀ3
)
Crystal dimensions (mm)
h range (°)
Reflections collected
Independent reflections
Rint
0.40 ꢃ 0.18 ꢃ 0.13 0.38 ꢃ 0.36 ꢃ 0.23 0.48 ꢃ 0.28 ꢃ 0.12 0.56 ꢃ 0.52 ꢃ 0.27 0.50 ꢃ 0.15 ꢃ 0.12 0.52 ꢃ 0.45 ꢃ 0.41
2.34–25.00
5849
1.71–25.01
19 238
1.35–25.01
13 467
4886
1.51–25.01
6654
1.35–25.02
10 800
3401
1.65–25.01
12 921
4688
3872
12 740
4450
0.0339
0.0486
0.0530
0.0291
0.0818
0.0582
Maximum and minimum transmission 0.8530 and 0.6319 0.7681 and 0.6561 0.8589 and 0.5725 0.7260 and 0.5371 0.7276 and 0.3319 0.4199 and 0.3493
Data/restraints/parameters
3872/1/298
1.489
12 740/2/799
0.969
4886/0/334
1.025
4450/2/317
0.958
3401/9/187
0.975
4688/0/325
1.000
Goodness-of-fit on F2
Final R indices [I > 2
R indices (all date)
r
(I)]
0.1188
0.1308
8.270 and ꢀ1.417
0.0879
0.1782
0.947 and ꢀ0.856
0.0395
0.0638
1.185 and ꢀ0.517
0.0462
0.0547
0.983 and ꢀ2.071
0.0456
0.0599
0.548 and ꢀ0.507
0.0451
0.0787
0.796 and ꢀ0.994
Largest difference in peak/hole [e Aꢀ3
]
about 1650–1640 cmꢀ1 are attributed to the
tC@N stretching
ical shift at 4.24 ppm moves to lowfield in the 1H NMR of com-
pound 5. In compound 5, the protons of the methyl group at
2.31 ppm are assigned to solvent molecules methanol. In com-
pounds 11 and 12, the chemical shift at 9.12 or 9.08 is assigned
to hydroxyl group of phenyl group. In the 13C NMR chemical
shifts, the nitrogen coordination of heterocyclic aprotic ligands
to metal atoms is manifested in the form of deshielding of the
C–4 carbon resonance by ꢂ3 ppm [35]. In compound 1, the C–4
resonance of 2-quinoline-carboxylate is little affected about
ꢂ3 ppm on coordination of the position for the free ligand sug-
gesting a presence of Sb–N coordination (see the crystal structure
of compound 1). In addition, the signals for carbons of C@N bonds
appear at about 154.2–158.7 ppm in compound 1. Besides that,
these derivatives also exhibit the expected signals due to the car-
bons of aryl groups at 120–155 ppm.
vibration, which shift to lower frequency than free ligands
(1680–1670 cmꢀ1). It is suggested that the coordination mode
of 2-quinoline-carboxylate ligands with antimony ions is biden-
tate by nitrogen atom. In addition, it is worthy to note that be-
sides the absorption at 1647 cmꢀ1 belonging to C@N, there is
another strong band at 593 cmꢀ1 attribute to
tSb–N in compound
1, which is consistent with the crystal structure of compound 1.
In addition, the frequencies of Sb–C deformations appear between
465 and 435 cmꢀ1 which is consistent with the literature [32]. In
the IR spectra of compounds 1–12, there is much common
ground. Comparing with dissociative COOH ligands, absorption
at 3250–3260 cmꢀ1 disappears and absorption of Sb–O bond at
450–480 cmꢀ1 appears. There are two strong absorption peaks
attribute to phenyl of arylantimony in the IR spectra of com-
pounds 1–12, one is at 770–730 cmꢀ1 and the other is at 710–
690 cmꢀ1, which is just the characteristic absorption peaks of
mono-substitution phenyl, however, absorption of phenyl of sub-
stitutional-benzo-carboxylates is complicated, however, it will
shift to lower frequency than free ligands when the ligands take
part in coordination to antimony atoms.
3.2. Crystal structure of compound 1
The colorless crystals of compound 1 were obtained from
CH2Cl2–petroleum ether. One of the approximate dimensions
0.40 ꢃ 0.18 ꢃ 0.13 mm was mounted in a glass capillary and used
for data collection. Molecular conformation and atomic numbering
schemes of compound 1 were illustrated in Fig. 1. The crystal struc-
ture of compound 1 can be reported as monomer. The most impor-
tant feature in this structure is the very strong secondary
interaction between antimony atom and the formally non-bonded
nitrogen of the quinoline group. This is the very interaction which
makes the coordination geometry of antimony to be converted
from a trigonal-bipyramid to a distorted octahedron. In molecular
structure of compound 1 (Fig. 1), the Sb atom is coordinated by the
2-quinoline-carboxylate ligand through an O atom and an imino N
atom. The N@C bond distance [1.32(2) Å] in this compound is man-
ifestations of the presence of a partial double bond, which suggests
that the band Sb–N is a copulate band [36]. The distance of Sb–N
[2.652(14) Å] is longer than that [2.259(4) Å and 2.249(4) Å] in ref-
erence [37]. There are hydrogen bonds in crystal structure of com-
pound 1. The selected bond lengths, angles and hydrogen bonds
are listed in Tables 2 and 3, respectively. In Fig. 2, C–Hꢁ ꢁ ꢁO hydro-
gen bonds link together adjacent molecules to one-dimension
3.1.1. 1H and 13C NMR (CDCl3)
In the 1H NMR chemical shifts, the protons of Ar show a com-
plicated multiplet between 6.82 and 9.24 ppm. All the protons in
the compounds have been identified and the total number of pro-
tons calculated from the integration curve tallies with what is ex-
pected from the molecular formula. It is noted that most changes
of the protons and 13Cs on the macroring are to lowfield from
shield by complexation [33,34]. The electronic structure on both
the macroring and sidearm is perturbed by complexation but
the macroring nuclei are more shielded while the sidearm nuclei
are less shielded [33]. It is helpful in understanding the formation
of weak H-bonds between a sidearm proton and an oxygen or
other donor atoms on the macroring. Although the 1H NMR
chemical shifts of the protons of Ar are important, they are com-
plicated multiplet. It is difficult to ascertain the protons of hydro-
gen-bonding interactions among carbon(Ar)–hydrogen–oxygen
(or chlorine and so on). For O–Hꢁ ꢁ ꢁO, it is evident that the chem-

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L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
3.721 Å and 4.196 Å, respectively, and the distance of H(26)-i
) is 3.177 Å [i is the center of phenyl C(17)–C(22); ii is the
(Hꢁ ꢁ ꢁ
p
center of phenyl C(23)–C(28); iii is the center of ring N(1)–C(6);
iv is the center of ring C(5)–C(10)].
3.3. Crystal structure of compound 5
A colorless crystal of compound 5 was obtained from CH2Cl2–
petroleum ether solution. In the molecular structure of compound
5 with atom numbering scheme is depicted in Fig. 3. The selected
bond distances and angles of the compound are listed in Table 4. As
shown in Fig. 3, the asymmetric unit [2(C32H19Cl6O4Sb)ꢁCH4O] con-
tains two crystallographically independent molecules A and B, to-
gether with one methanol solvent molecules. Between the
independent molecules, there are intermolecular hydrogen bonds
C–Hꢁ ꢁ ꢁO, which link them together. Conformations of the two inde-
pendent molecules are almost the same, with only few differences
in bond lengths and angles. The coordination about the Sb atom is
slightly distorted from regular trigonal-bipyramidal geometry,
with the equatorial plane occupied by three a-C from three phenyl
groups and the axial positions shared by one coordinated oxygen
atom from the ligand. The Sb–O distances [2.114(8), 2.145(8),
2.106(10), 2.130(10) Å] are within the literatures [38–41] but
shorter than the sum of the van der Waals radii for Sb and O
(3.2 Å) [42]. The angles of O(1)–Sb(1)–O(3) and O(5)–Sb(2)–O(7)
are, respectively, 176.6(3)° and 176.0(3)°, showing quasi linear
Fig. 1. The molecular structure of compound 1.
Table 2
Selected bond lengths (Å) and angles (°) for compound 1.
arrangement. The sum of the equatorial angles subtended at the
Sb(1)–O(1)
Sb(1)–N(1)
Sb(1)–Cl(1)
C(2)–N(1)
C(23)–Sb(1)–Cl(1)
O(1)–Sb(1)–N(1)
C(23)–Sb(1)–Cl(1)
O(1)-Sb(1)-Cl(1)
2.065(12)
2.652(14)
2.466(4)
1.32(2)
99.1(5)
71.6(4)
Sb(1)–C(17)
Sb(1)–C(11)
Sb(1)–C(23)
N(1)-C(6)
O(1)–Sb(1)–C(23)
C(17)–Sb(1)–C(11)
Cl(1)–Sb(1)–N(1)
2.127(16)
2.166(16)
2.13(2)
1.32(2)
87.1(6)
0
Sb atoms is 360.0°. The Sb–C distances [2.094(13)–2.146(13) ÅA]
are equal within experimental error and close to the single-bond
value for trigonal-bipyramidal antimony. Similarly dimeric struc-
tures are formed through C–Hꢁ ꢁ ꢁO hydrogen bonds between the
independent molecules A and B in the asymmetric unit. Compara-
tively, two adjacent solvent molecules also form a similarly di-
meric structure but through O–Hꢁ ꢁ ꢁO hydrogen bonds (Fig. 4).
The hydrogen bonds are listed in Table 5.
156.3(6)
102.3(3)
99.1(5)
173.3(4)
Table 3
Hydrogen bonds (Å, °) for compound 1.
3.4. Crystal structure of compound 6
D–Hꢁ ꢁ ꢁA
d(Hꢁ ꢁ ꢁA)
d(Dꢁ ꢁ ꢁA)
Symmetry code
—DHA
A colorless crystal of compound 6 was obtained from CH2Cl2–
petroleum ether solution. The molecular structures of compound
6 with the atom numbering scheme is depicted in Fig. 5. The
selected bond distances and angles of the compound are listed in
Table 6. The crystal structure of compound 6 can be reported as
monomer. The antimony atom of the compound is five-coordinate,
the coordination geometry of antimony can be described as a
C4–H4ꢁ ꢁ ꢁO2
2.50
2.64
140.5
124.6
3.27
3.26
1 ꢀ x, 0.5 + y, 2 ꢀ z
1 ꢀ x, ꢀ0.5 + y, 2 ꢀ z
C15–H15ꢁ ꢁ ꢁO2
chain towards b axis. Furthermore, there are
interactions in the one-dimension chain, which make the structure
is more stable. The distance of ii–iii ( ) and ii–iv ( ꢁ ꢁ ꢁ ) is
ꢁ ꢁ ꢁ
pꢁ ꢁ ꢁ
p
and C–Hꢁ ꢁ ꢁ
p
p
p
p p
Fig. 2. One-dimension chain of compound 1.

L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
3713
Fig. 3. The molecular structure of compound 5.
distorted trigonal-bipyramid. The three equatorial positions are
occupied by the carbon atoms [C(14), C(20) and C(26)] of the three
phenyl groups, while the atoms C(8) and O(1) occupy the axial
positions. The apical Sb(1)–C(8) distance [2.174(4) Å] is slightly
longer than the equatorial Sb(1)–C(14), Sb(1)–C(20) and Sb(1)–
C(26) distances [2.127(4), 2.112(5) and 2.119(4) Å, respectively].
The Sb(1)–O(1) distance [2.305(3) Å] is longer than the corre-
sponding distance in Ph4SbOMe [2.061(7) Å] [43] and also longer
than the typical Sb–O value [14]. A pair of weak C–Hꢁ ꢁ ꢁCl
[C(16)ꢁ ꢁ ꢁCl(2) = 3.677(6) Å,
H(16)ꢁ ꢁ ꢁCl(2) = 2.86 Å,
C(16)–
H(16)ꢁ ꢁ ꢁCl(2) = 147.0°] interactions generates similarly dimeric
structures via crystallographic inversion centers (Fig. 6).
3.5. Crystal structure of compound 8
A colorless crystal of compound 8 was obtained from CH2Cl2–
petroleum ether solution. The molecular structure of compound
8 with the atom numbering scheme is depicted in Fig. 7. The se-
Table 4
Selected bond lengths (Å) and angles (°) for compound 5.
Sb(1)–C(27)
Sb(1)–C(15)
Sb(1)–O(1)
Sb(1)–O(3)
2.094(13)
2.107(12)
2.114(8)
2.145(8)
2.146(13)
108.5(5)
142.9(5)
176.6(3)
108.6(5)
Sb(2)–C(53)
Sb(2)–O(5)
Sb(2)–C(59)
Sb(2)–O(7)
2.142(15)
2.106(10)
2.119(15)
2.130(10)
2.139(16)
109.2(6)
106.9(6)
143.9(6)
176.0(3)
Table 5
Hydrogen bonds (Å, °) for compound 5.
Sb(1)–C(21)
Sb(2)–C(47)
D–Hꢁ ꢁ ꢁA
d(Hꢁ ꢁ ꢁA)
<DHA
d(Dꢁ ꢁ ꢁA)
Symmetry code
C(27)–Sb(1)–C(15)
C(15)–Sb(1)–C(21)
O(1)–Sb(1)–O(3)
C(27)–Sb(1)–C(21)
C(59)–Sb(2)–C(47)
C(59)–Sb(2)–C(53)
C(47)–Sb(2)–C(53)
O(5)–Sb(2)–O(7)
C63–H63ꢁ ꢁ ꢁO4
C62–H62ꢁ ꢁ ꢁO2
O11–H11aꢁ ꢁ ꢁO11
2.71
2.50
1.79
137.7
168.7
95.7
3.459(19)
3.416(19)
2.04(8)
+x, 1 + y, +z
+x, 1 + y, +z
1 ꢀ x,1 ꢀ y, 1 ꢀ z
Fig. 4. Similarly dimeric structures of compound 5.

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L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
Table 6
Selected bond lengths (Å) and angles (°) for compound 6.
Sb(1)–C(20)
Sb(1)–C(26)
Sb(1)–C(14)
C(20)–Sb(1)–C(14)
C(20)–Sb(1)–C(8)
C(26)–Sb(1)–C(8)
2.112(5)
2.119(4)
2.127(4)
115.12(17)
94.72(18)
94.92(17)
Sb(1)–O(1)
Sb(1)–C(8)
C(20)–Sb(1)–C(26)
C(26)–Sb(1)–C(14)
C(14)–Sb(1)–C(8)
C(8)–Sb(1)–O(1)
2.305(3)
2.174(4)
131.36(17)
110.29(18)
98.63(17)
178.76(15)
lected bond distances and angles of the compound are listed in Ta-
ble 7. From Table 7, we can see that around Sb atom there are two
short Sb–O bonds and a long one, indicating strong coordination
and weak interaction. The distances of the long Sb–O bonds are
much shorter than the sum of van der Waals radii of Sb and O
atom, 3.2 Å [42] and are different from the corresponding distances
in Ph3Sb(O2C–2-C4H3S)2 [2.744(4), 2.949(4) Å] [24]. Obviously,
there is apparent weak intramolecular Sbꢁ ꢁ ꢁO interaction in this
compound. Therefore, the Sb atom could be described as three cen-
ter four electron bond for the octahedron geometry. The central
Sb1 atom is surrounded axially by O(1) and O(3) atoms and equa-
torially by C(11), C(17), C(23). The sum of equatorial angles is
359.84° which shows that these atoms are almost coplanar. Fur-
thermore, the angle of axial place O(3)–Sb(1)–O(1) is
176.89(13)°, slightly deviating from 180°. In the crystal structure
C–Hꢁ ꢁ ꢁO [C(21)ꢁ ꢁ ꢁO(4) = 3.610(8) Å, H(21)ꢁ ꢁ ꢁO(4) = 2.68 Å, C(21)–
H(21)ꢁ ꢁ ꢁO(4) = 178.4°] hydrogen bonds link adjacent molecules to
generate a one–dimensional chain along a axis (Fig. 8a) spreading
Fig. 5. The molecular structure of compound 6.
towards b axis through C–Hꢁ ꢁ ꢁ
p(C23–C28) (dH10ꢁ ꢁ ꢁ = 2.60 Å) inter-
action to form a 2D network (Fig. 8b).
p
3.6. Crystal structure of compound 11
A colorless crystal of compound 11 was obtained from CH2Cl2–
petroleum ether solution. The molecular structures of compound
11 with the atom numbering scheme is depicted in Fig. 9. The se-
lected bond distances and angles of the compound are listed in Ta-
ble 8. The crystal structure of compound 11 can be reported as
monomer lying on a 2-fold axis defined by the Sb atom and the
ipso- and para-C atoms of one of the three antimony bound phenyl
rings. The coordination environment of the Sb atom is trigonal-
bipyramidal with the three phenyl substituents in the equatorial
plane and the two monodentate benzoate ligands axial. The struc-
Fig. 6. Cell of compound 6. In the crystal structure C–Hꢁ ꢁ ꢁCl hydrogen bonds link
adjacent molecules into a dimmer [C16–H16ꢁ ꢁ ꢁCl2#1 0.93, 2.86, 3.677(6), 147.0,
#1: ꢀx + 1, ꢀy, ꢀz + 1].
Fig. 7. The molecular structure of compound 8.

L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
3715
Fig. 8. (a) A 1D chain of compound 8 and (b) a 2D network of compound 8.
ture of compound 11 comprised isolated molecules with C2 molec-
ular symmetry. The C2 axis was defined by the Sb(1)–C(14)–C(17)
atoms. The coordination geometry around the antimony center is
best described as a trigonal-bipyramid with two monodentate car-
boxylate ligands occupying the apical sites with an O(1)–Sb(1)–
O(1a) angle 172.8(3)°. In the equatorial plane the angles C(8)–
Sb(1)–C(8a) 134.1(4)°, C(8)–Sb(1)–C(14) 112.9(2)° and C(14)–
Sb(1)–C(8a) 112.9(2)° depart significantly from 120° indicating
some steric crowding in the molecule. The Sb(1)–O(1) bond dis-
tance 2.132(4) Å was longer than the corresponding distance
2.087(6) Å in [4–(C5H5FeC5H4)C6H4COO]2Sb(C6H4F-4)3 [44], but is
rather shorter than the sum of van der Waals’ radii of antimony
and oxygen atom (2.2 and 1.4 Å, respectively) [42], as were the cor-
responding Sb–C distances 2.063(10)–2.130(6) Å compared to
2.123(9)–2.219(15) Å [38]. In the crystal structure C(15)–
H(15)ꢁ ꢁ ꢁBr(1) hydrogen bonds link adjacent molecules into one-
dimensional chains (Fig. 10a) via crystallographic inversion cen-
ters. Among these chains, every six of them are linked into a chan-
nel by C11–H11ꢁ ꢁ ꢁO1 hydrogen bonds. Simultaneously, these
channels are linked together into
a 3D alveolate structure
(Fig. 10b) through C11–H11ꢁ ꢁ ꢁO1 hydrogen bonds. Furthermore,
Table 7
Selected bond lengths (Å) and angles (°) for compound 8.
Sb(1)–O(3)
Sb(1)–C(11)
Sb(1)–C(17)
Sb(1)–C(23)
Sb(1)–O(1)
Sb(1)–O(4)
2.109(4)
2.128(5)
2.132(5)
2.139(5)
2.161(3)
2.970(4)
Sb(1)–O(2)
2.758(3)
C(11)–Sb(1)–C(17)
C(11)–Sb(1)–C(23)
O(3)–Sb(1)–O(1)
C(17)–Sb(1)–C(23)
109.46(18)
104.59(19)
176.89(13)
145.79(19)
Fig. 9. The molecular structure of compound 11.

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L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
Fig. 10. (a) One-dimensional chain of compound 11; (b) 3D alveolate structure of compound 11 {C15–H15ꢁ ꢁ ꢁBr1#1 and C15a–H15aꢁ ꢁ ꢁBr1#2 [0.93, 2.99, 3.823(8), 149.8] #1:
x, y, z ꢀ 1 and #2: x ꢀ y + 1, ꢀy + 2, ꢀz + 1/3; C11–H11ꢁ ꢁ ꢁO1#1 and C11A–H11Aꢁ ꢁ ꢁO1#2 [0.93, 2.61, 3.532(10), 170.0] #1: 1 ꢀ y, 1 + x ꢀ y, ꢀ0.333330 + z and #2: 1 ꢀ x,
1 ꢀ x + y, 0.66667 ꢀ z}.
C–Hꢁ ꢁ ꢁ
p
interactions between H5s and phenyls (C8–C13) make the
compound 12 with the atom numbering scheme is depicted in
Fig. 11. The selected bond distances and angles of the compound
are listed in Table 9. This tretraphenylantimony derivative is
synthesized by different method from Refs. [21,28], but the crys-
tal structures are reported as similar monomers and the Sb
atoms have the same distorted trigonalbipyramidal coordination
with the O atoms of the carboxylate ligands in the axial posi-
tions while carbon atoms of the SbPh3 unit occupy equatorial
positions. In the crystal structure of compound 12, in the axial
position the angle C(26)–Sb(1)–O(1) is 175.44(14)°. The distance
of Sb–O in compound 12 is slightly longer than that in tri-m-tol-
ylantimony bis(benzenesulfonate), tri-p-tolylantimony bis(2,5-
dimethylbenzenesulfonate) [21], tetraphenylantimony 2-furoi-
nate and tetraphenylantimony benzoate [28]. Furthermore, the
antimony–oxygen distance is different from Sb–O(H) 1.967(3) Å
and Sbꢁ ꢁ ꢁO(P) 2.235(2) Å [44].
3D network more stable (dH5-i = 2.682 Å).
3.7. Crystal structure of compound 12
A
colorless crystal of compound 12 was obtained from
CH2Cl2–petroleum ether solution. The molecular structures of
Table 8
Selected bond lengths (Å) and angles (°) for compound 11.
Sb(1)–C(14)
Sb(1)–C(8)
Sb(1)–O(1)
Sb(1)–O(1)#1
C(14)–Sb(1)–C(8)
C(14)–Sb(1)–C(8)#1
2.063(10)
2.130(6)
2.132(4)
2.132(4)
112.9(2)
112.9(2)
O(3)–H(3)
0.8200
C(8)–Sb(1)–C(8)#1
C(8)–Sb(1)–O(1)#1
C(8)#1–Sb(1)–O(1)#1
O(1)–Sb(1)–O(1)#1
134.1(4)
92.01(18)
90.80(19)
172.8(3)
Symmetry code: #1 x ꢀ y + 1, ꢀy + 2, ꢀz + 1 ꢀ 3.

L. Quan et al. / Journal of Organometallic Chemistry 694 (2009) 3708–3717
3717
Fig. 11. The molecular structure of compound 12.
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[16] M.N. Gibbons, D.B. Sowerby, J. Organomet. Chem. 555 (1998) 271.
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536–537 (1997) 87.
[18] M.N. Gibbons, D.B. Sowerby, J. Organomet. Chem. 555 (1998) 271.
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Fukin, L.N. Zakharov, Russ. J. Gen. Chem. 73 (2003) 354.
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(2003) 662.
Selected bond lengths (Å) and angles (°) for compound 12.
Sb(1)–C(8)
Sb(1)–C(20)
Sb(1)–C(26)
C(8)–Sb(1)–C(20)
C(8)–Sb(1)–C(14)
C(20)–Sb(1)–C(14)
C(8)–Sb(1)–C(26)
2.107(5)
2.110(5)
2.167(5)
130.45(19)
112.89(19)
111.93(19)
94.78(19)
Sb(1)–O(1)
Sb(1)–C(14)
C(14)–Sb(1)–O(1)
C(26)–Sb(1)–O(1)
C(14)–Sb(1)–C(26)
C(20)–Sb(1)–C(26)
2.369(3)
2.118(4)
84.42(16)
175.44(14)
100.10(17)
97.23(19)
Supplementary material
CCDC 679197, 731491, 731490, 731489, 731488 and 731487
contain the supplementary crystallographic data for this paper.
These data can be obtained free of charge from The Cambridge
Crystallographic Data Centre via http://www.ccdc.cam.ac.uk/da-
ta_request/cif.
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Organomet. Chem. 690 (2005) 151.
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Acknowledgements
[29] V.V. Sharutin, O.K. Sharutina, V.S. Senchurin, T.P. Platonova, N.V. Nasonova, A.P.
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We acknowledge the National Natural Foundation of China
(20771053), the Natural Science Foundation of Shandong Province
(Y2008B48) for financial support. And this work was supported by
shangdong ‘‘Tai-Shan Scholar Research Fund”.
[33] S.W. Ding, Y.W. Hong, C.Y. Chen, N.C. Chang, Biophys. Chem. 121 (2006) 75.
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