Crystal structures of 1,3,5-Tris(bromomethyl)-2,4,6-trimethylbenzene and 2,4,6-trimethyl-1,3,5-tris(4-oxymethyl-1-formylphenyl)benzene

Article abstract of DOI:10.1007/s10870-011-0219-z

The synthesis and X-ray crystal structure of 2,4,6-trimethyl-1,3,5-tris(4- oxymethyl-1-formylphenyl)benzene (2) and the crystal structure of its core molecule, 1,3,5-tris(bromomethyl)-2,4,6-trimethylbenzene (1) are reported. The compounds 1 and 2 crystallize in the triclinic system with space group P i. The lattice parameters of 1 and 2 are a = 9.454(2) A, b = 9.478(4) A, c = 9.573(2) A, α = 116.53(2)°, β = 109.705(14)°, γ = 101.293(18)°, V = 658.5(4) and a = 15.7707(6) A, b = 16.3646(5) A, c = 18.2805(6) A, α = 83.202(2)°, β = 66.0120(10)°, γ = 73.704(2)°, V = 4137.2(2), respectively. In the crystals of 1 and 2, there are one and three molecules in the asymmetric unit, respectively. The packing of the molecules in the solid is stabilized through van der Waals interactions in 1 and weak C-H???O and C-H???π interactions in 2.

Full text of DOI:10.1007/s10870-011-0219-z

J Chem Crystallogr (2012) 42:165–172
DOI 10.1007/s10870-011-0219-z
ORIGINAL PAPER
Crystal Structures of 1,3,5-Tris(bromomethyl)-2,4,6-
trimethylbenzene and 2,4,6-Trimethyl-1,3,5-tris(4-oxymethyl-1-
formylphenyl)benzene
•
N. Arockia Samy V. Alexander
Received: 4 June 2011 / Accepted: 17 November 2011 / Published online: 30 November 2011
Ó Springer Science+Business Media, LLC 2011
Abstract The synthesis and X-ray crystal structure of
2,4,6-trimethyl-1,3,5-tris(4-oxymethyl-1-formylphenyl)ben-
zene (2) and the crystal structure of its core molecule, 1,3,
5-tris(bromomethyl)-2,4,6-trimethylbenzene (1) are repor-
ted. The compounds 1 and 2 crystallize in the triclinic
system with space group P ¯ı. The lattice parameters of 1 and
their interesting properties and potential use as functional
materials [1–5]. Important properties and functions of
MOFs depend largely on their structures and topology and
hence the selection of organic building blocks is key to the
construction of desired frameworks [6]. In this article, we
report the synthesis and crystal structure of 2,4,6-trimethyl-
1,3,5-tris(4-oxymethyl-1-formylphenyl)benzene and the
crystal structure of its core molecule, 1,3,5-tris(bromo-
methyl)-2,4,6-trimethylbenzene. 1,3,5-Tris(bromomethyl)-
2,4,6-trimethylbenzene is a good core molecule due to the
presence of three bromomethyl groups to synthesize dif-
ferent kinds of dendritic molecules.
˚
2 are a = 9.454(2) A, b = 9.478(4) A, c = 9.573(2) A,
˚
˚
a = 116.53(2)°, b = 109.705(14)°, c = 101.293(18)°, V =
˚
658.5(4) and a = 15.7707(6) A, b = 16.3646(5) A, c =
˚
˚
18.2805(6) A, a = 83.202(2)°, b = 66.0120(10)°, c = 73.704(2)°,
V = 4137.2(2), respectively. In the crystals of 1 and 2,
there are one and three molecules in the asymmetric unit,
respectively. The packing of the molecules in the solid is
stabilized through van der Waals interactions in 1 and weak
C–HꢀꢀꢀO and C–Hꢀꢀꢀp interactions in 2.
Experimental
Keywords Crystal structure ꢀ Benzaldehyde ꢀ
Tris(methyl)benzene ꢀ Hydrogen bonding
Physical Measurements
Elemental microanalyses were carried out using a Perkin-
Elmer 2400 Series II CHNS/O Elemental Analyzer inter-
faced with a Perkin-Elmer AD 6 Autobalance. Helium was
used as the carrier gas. Infrared spectra were recorded on a
Perkin-Elmer Spectrum RX-I FT IR spectrometer in the
range 4000–400 cm-1 using KBr pellets. NMR spectra
were recorded on a Bruker AVANCE III 500 MHz (AV
500) multinuclear NMR spectrometer working at 500 MHz
Introduction
In the recent years, design and construction of multidi-
mensional metal-organic frameworks (MOFs) have attrac-
ted considerable attention in crystal engineering owing to
1
at 25 °C. Standard 5 mm probe was used for the H and
13C NMR measurements. The electrospray ionization mass
spectra (ESI MS) were performed using a Micromass
Quattro-II Triple Quadrupole mass spectrometer. The
samples were dissolved in acetonitrile and introduced into
the ESI capillary using a 5 lL syringe pump. The
ESI capillary was set at 3.5 kV with the cone voltage of
40 V. The solvents were purified and dried using standard
procedures [7].
N. Arockia Samy ꢀ V. Alexander (&)
Department of Chemistry, Loyola College,
Chennai 600034, India
e-mail: valexander@rediffmail.com
N. Arockia Samy
e-mail: narockiasamy@gmail.com
123

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J Chem Crystallogr (2012) 42:165–172
Scheme 1 Synthesis of 2,4,6-
trimethyl-1,3,5-tris(4-
oxymethyl-1-
O
O
formylphenyl)benzene
Br
O
O
OH
K2CO3, DMF
80 oC, 24 h
+
3
Br
O
Br
O
1
2
O
Synthesis of 1,3,5-Tris(bromomethyl)-2,4,
6-trimethylbenzene (1)
Compound 1 was synthesized by the procedure reported by
Zavada et al. [8]. To a mixture of mesitylene (4.16 mL,
30 mmol), paraformaldehyde (4.20 g, 140 mmol), and
potassium bromide (19.20 g, 160 mmol) in acetic acid
(32 mL) was added a mixture of concentrated sulfuric acid
and acetic acid (1:1 v/v, 30 mL) dropwise, stirred at
90–95 °C for 6 h, allowed to stand overnight, and poured
into water (1.6 L) at room temperature. The solid product
that separated out was filtered, dried in vacuum, and
recrystallized twice in ether-dichloromethane (1:1 v/v)
to get colorless crystals suitable for X-ray diffraction.
Yield 9.44 g (78%). mp 188–189 °C. Anal. Calcd. for
C12H15Br3: C 36.10, H 3.79. Found: C 36.00, H 3.69. IR
(KBr, cm-1): 3,039 ms(C–H) and 754 d(C–H) (aromatic);
2,997 mas(C–H) and 2,920 ms(C–H) (aliphatic); 1,569 and
1,446 ms(C=C) (aromatic). 1H NMR (CDCl3, 298 K): d
2.48 (s, 9H, –CH3), 4.59 (s, 6H, –CH2). 13C NMR (CDCl3,
298 K): d 15.4, 29.9, 133.2, 137.9.
Fig. 1 ORTEP view of 1,3,5-tris(bromomethyl)-2,4,6-trimethylben-
zene (1)
Fig. 2 ORTEP representation
of the asymmetric unit of 2. The
atoms are not labeled for the
sake of clarity
123

J Chem Crystallogr (2012) 42:165–172
167
Fig. 3 ORTEP view of 2,4,6-
trimethyl-1,3,5-tris(4-
oxymethyl-1-
formylphenyl)benzene (2)
showing the atom labeling
scheme of a molecule A of the
asymmetric unit. The
displacement ellipsoids are
drawn at the 40% probability
level. Molecules B and C are
not drawn for the sake of clarity
Fig. 4 Crystal packing of the molecule 1 in the unit cell
Synthesis of 2,4,6-Trimethyl-1,3,5-tris(4-oxymethyl-1-
formylphenyl)benzene (2)
Fig. 5 Crystal packing of the molecule 2 in the unit cell. The
intermolecular interactions are shown with dotted lines
To a solution of 4-hydroxybenzaldehyde (1.47 g, 12 mmol)
in dry DMF (100 mL) was added potassium carbonate
(1.93 g, 14 mmol) and stirred for 15 min under an atmo-
sphere of argon. 1,3,5-Tris(bromomethyl)-2,4,6-trimethyl-
benzene (1.60 g, 4 mmol) in dry DMF (40 mL) was added
dropwise over a period of 15 min, heated at 80 °C for 24 h,
cooled to room temperature, and flash evaporated. The
resulting crude product was dissolved in chloroform
(100 mL), washed with water (3 9 100 mL), the organic
layer was dried over sodium sulfate overnight, and filtered.
The chloroform extract was flash evaporated and the
resulting solid product was recrystallized in hot ethanol to
get pale yellow crystals suitable for X-ray diffraction. The
reaction is illustrated in Scheme 1. Yield 1.76 g (84%).
Anal. Calcd. for C33H30O6: C 75.84, H 5.79. Found: C
75.77, H 5.72. IR (KBr, cm-1): 2,926 mas(CH2), 1,690
ms(C=O), 1,600 ms(C=C) (aromatic), 1,508 ms(C–C), 1,311
1
s(CH2), 1,244 mas(C–O–C), 830 s(C–H). H NMR (CDCl3,
298 K): d 2.47 (s, 9H, –CH3), 5.23 (s, 6H, –O–CH2–), 7.15
(d, 6H, J = 8.5 Hz, Ph-H), 7.90 (d, 6H, J = 7 Hz, Ph-H),
9.92 (s, 3H, –CHO). 13C NMR (CDCl3, 298 K): d 16.0,
123

168
J Chem Crystallogr (2012) 42:165–172
65.2, 114.8, 130.3, 131.2, 132.1, 139.7, 163.9, 190.7. ESI
MS: m/z 546 [M?Na]?, 523 [M]?, 375 [M-(C9H10O2)]?,
102 [M-(C26H28O5)]?.
Single-Crystal X-ray Diffraction
X-ray diffraction studies were carried out using Bruker axs
kappa Apex II single crystal X-ray diffractometer equipped
˚
with graphite monochromated Mo(Ka) (k = 0.7107 A)
radiation and CCD detector. Crystals were cut to suitable
size and mounted on a glass fiber using cyanoacrylate
adhesive. The unit cell parameters were determined from
36 frames measured (0.5° phi-scan) from three different
crystallographic zones using the method of difference
vectors. The intensity data was collected with an average
four-fold redundancy per reflection and optimum resolution
˚
(0.80 A). The intensity data collection, integration of
Fig. 6 The 3D supramolecular structure of 2 via hydrogen bonding
interactions
frames, LP and decay corrections were carried out using
Table 1 The crystal structure
data and structure refinement
parameters of 1 and 2
Description
1
2
Empirical formula
Formula weight
Color
C12H15Br3
C33H30O6
398.97
522.57
Colorless
Yellow
Crystal description
Crystal size/mm
Diffractometer
Radiation type
Crystal system
Space group
Block
Prism
0.3 9 0.25 9 0.2
0.2 9 0.16 9 0.16
Bruker axs kappa apex2 CCD
Bruker axs kappa apex2 CCD
MoKa
MoKa
Triclinic
Triclinic
P ¯ı
P ¯ı
˚
a (A)
9.454(2)
15.7707(6)
16.3646(5)
18.2805(6)
83.202(2)
66.0120(10)
73.704(2)
4137.2(2)
6
˚
b (A)
9.478(4)
˚
c (A)
9.573(2)
a (°)
b (°)
c (°)
116.530(2)
109.705(14)
101.293(18)
3
˚
V (A )
658.5(4)
Z
2
qcalcd (mg cm-3
)
2.012
1.258
˚
k (A)
0.71073
0.71073
T (K)
293(2) K
293(2) K
Absorption correction
Absorption correction range
2h range (°)
Multi-scan
Multi-scan
0.9830–0.9864
1.30–24.44
1,656
0.1698–0.2618
2.51–28.56
F(000)
384
No. of reflections collected
No. of independent reflections
No. of parameters
14,861
73,977
3,337
13,594
140
1,065
Goodness-of-fit on F2
Final R indices [I [ 2r(I)]
Ra indices, all data
1.045
1.020
R1 = 0.0342, wR2 = 0.0781
R1 = 0.0598, wR2 = 0.0853
0.836 and -0.814
9.156
R1 = 0.0582, wR2 = 0.1689
R1 = 0.1003, wR2 = 0.2121
0.656 and -0.225
0.086
P
P
a
R ¼ jjFoj ꢁ jFcjj= jFoj:
h
n
o
ꢀ
ꢁ
P
2
Largest diff. peak and hole
Absorption coefficient
Rw
P
¼
w Fo2 ꢁ Fo2
=
n
o
ꢀ
ꢁ
2
1=2
w Fo2
ꢂ
123

J Chem Crystallogr (2012) 42:165–172
169
the 1,3,5-positions of 1,3,5-tris(methylene)-2,4,6-trimethyl-
benzene.
Table 2 Hydrogen bonds for 2,4,6-trimethyl-1,3,5-tris(4-oxymethyl-
˚
1-formylphenyl)benzene (2) (A and °)
1
The H NMR spectrum of 2 in CDCl3 shows five reso-
D–HꢀꢀꢀA
d(D–H) d(HꢀꢀꢀA) d(DꢀꢀꢀA) \(DHA)
nances. The methyl (–CH3) and the methylene (–CH2–) pro-
tons resonate at 2.47 and 5.23 ppm, respectively. The phenyl
protons resonanate at 7.15 and 7.90 ppm. The aldehyde
(–CHO) protons resonate at 9.92 ppm. The 13C NMR spec-
trum of 2 in CDCl3 shows nine resonances for nine different
types of carbon atoms. The methyl carbons and the methylene
carbons resonate at 16.0 and 65.2 ppm, respectively. The aryl
carbons resonate at 114.8, 130.3, 132.1, and 163.9 ppm. The
aldehyde (–CHO) carbons resonate at 190.7 ppm.
C(31B)–H(31D)ꢀꢀꢀO(4C)#1 0.960
C(26B)–H(26B)ꢀꢀꢀO(6C)#2 0.930
2.535
2.523
2.580
3.447
3.342
3.368
158.68
147.0
143.0
C(10A)–(10A)ꢀꢀꢀO(4C)#3
0.930
Symmetry transformations used to generate equivalent atoms: #1-x ? 1,
#2 #3
-y ? 1, -z; -x ? 1, -y, -z ? 1; -x ? 2, -y ? 1, -z
SAINT-NT (version 7.06a) software [9]. Empirical
absorption correction (multi-scan) was performed using
SADABS (1999) program [10]. The structure was solved
using SIR92 [11] and refined using SHELXL-97 [12]
programs. All non-hydrogen atoms were refined with
anisotropic displacement parameters. Hydrogen atoms
were geometrically fixed at chemically meaningful posi-
tions and were allowed to ride over the parent atoms during
refinement.
The compounds 1 and 2 crystallize in the triclinic sys-
tem with the space group P ¯ı. In the crystal of 1 there is one
molecule in the asymmetric unit, whereas in 2 there are
three molecules in the asymmetric unit. The ORTEP rep-
resentation of 1 is shown in Fig. 1. The ORTEP repre-
sentation of the asymmetric unit of 2 and the atom labeling
scheme are depicted in Figs. 2 and 3, respectively. The
displacement ellipsoids are drawn at 40% probability level.
The crystal packing of the molecules 1 and 2 in the unit cell
are shown in Figs. 4 and 5, respectively. In 2, the packing
is stabilized mostly through the C–HꢀꢀꢀO interactions and
van der Waals forces. The mean plane of all the three
oxybenzaldehyde moieties are nearly perpendicular to the
mean plane of the tris(methyl)benzene core. The corre-
sponding angle between the mean planes of p-oxybenzal-
dehyde moieties considerably differ among the three
molecules in the asymmetric unit. This shows that the three
Results and Discussion
Compound 1 was synthesized by the bromomethylation of
mesitylene with potassium bromide and paraformaldehyde
[8]. Compound 2 was synthesized by the O-alkylation of
4-hydroxybenzaldehyde (3 equiv) with 1,3,5-tris(bromo-
methyl)-2,4,6-trimethylbenzene (1 equiv) in DMF. In 2,
three oxybenzaldehyde moieties are covalently appended at
Table 3 Summary of selected
˚
bond lengths (A), bond angles
(°), and torsion angles (°) with
e.s.d. in parentheses for 2
Bond
Angle
106.9(2)
Bond
Length
O(1A)–C(7A)–C(1A)
C(1A)–C(7A)
C(2A)–C(32A)
C(3A)–C(15A)
C(4A)–C(33A)
C(5A)–C(23A)
C(6A)–C(31A)
C(7A)–O(1A)
C(8A)–O(1A)
C(14A)–O(2A)
C(15A)–O(3A)
C(16A)–O(3A)
C(22A)–O(4A)
C(23A)–O(5A)
C(24A)–O(5A)
C(30A)–O(6A)
1.501(4)
1.510(4)
1.501(4)
1.505(4)
1.504(4)
1.513(4)
1.435(3)
1.353(3)
1.336(12)
1.444(3)
1.361(3)
1.187(5)
1.435(3)
1.363(3)
1.179(4)
C(8A)–O(1A)–C(7A)
118.4(2)
117.6(8)
106.5(2)
118.9(2)
125.8(4)
108.0(2)
117.0(2)
125.6(4)
O(2A)–C(14A)–C(11A)
O(5A)–C(23A)–C(5A)
C(24A)–O(5A)–C(23A)
O(6A)–C(30A)–C(27A)
O(3A)–C(15A)–C(3A)
C(16A)–O(3A)–C(15A)
O(4A)–C(22A)–C(19A)
C(9A)–C(8A)–O(1A)–C(7A)
C(13A)–C(8A)–O(1A)–C(7A)
C(1A)–C(7A)–O(1A)–C(8A)
C(17A)–C(16A)–O(3A)–C(15A)
C(21A)–C(16A)–O(3A)–C(15A)
C(3A)–C(15A)–O(3A)–C(16A)
C(29A)–C(24A)–O(5A)–C(23A)
C(25A)–C(24A)–O(5A)–C(23A)
C(5A)–C(23A)–O(5A)–C(24A)
5.8(5)
-172.6(3)
167.3(3)
13.8(4)
-166.0(3)
169.1(2)
2.9(4)
-177.9(3)
-167.7(2)
123

170
J Chem Crystallogr (2012) 42:165–172
Table 4 Atomic coordinates and thermal parameters for 2
Table 4 continued
x
y
z
U(eq)
x
y
z
U(eq)
C(1A)
C(2A)
C(3A)
C(4A)
C(5A)
C(6A)
C(7A)
C(8A)
C(9A)
C(10A)
C(11A)
C(12A)
C(13A)
C(14A)
C(15A)
C(16A)
C(17A)
C(18A)
C(19A)
C(20A)
C(21A)
C(22A)
C(23A)
C(24A)
C(25A)
C(26A)
C(27A)
C(28A)
C(29A)
C(30A)
C(31A)
C(32A)
C(33A)
O(1A)
O(2A)
O(2A0)
O(3A)
O(4A)
O(5A)
O(6A)
C(1B)
11977(2)
11053(2)
10394(2)
10655(2)
11583(2)
12243(2)
12704(2)
13376(2)
14099(2)
14787(3)
14773(3)
14056(3)
13355(2)
15548(4)
9381(2)
8329(2)
7566(2)
6676(2)
6529(2)
7303(3)
8194(2)
5575(3)
11886(2)
12097(2)
11873(2)
12216(2)
12804(2)
13021(3)
12667(3)
13201(3)
13233(2)
10765(3)
9931(2)
12666(1)
15710(9)
15310(20)
9245(1)
5387(2)
11720(2)
13052(2)
6194(2)
6481(2)
6428(2)
6065(2)
5824(2)
5893(2)
6208(2)
7389(2)
4847(2)
5141(2)
4652(2)
3868(2)
3580(2)
4072(2)
5360(2)
6221(2)
6252(2)
6651(3)
7018(3)
6970(3)
6580(2)
7415(5)
4957(2)
4469(2)
5147(2)
5161(2)
4510(2)
3829(2)
3801(2)
4541(3)
2742(2)
2309(2)
2534(2)
1971(2)
1174(2)
966(2)
3595(2)
3597(2)
3974(2)
4338(2)
4313(2)
3959(2)
3216(2)
3689(2)
2946(2)
2867(2)
3508(3)
4253(3)
4346(2)
3378(4)
4026(2)
3639(2)
3995(2)
4035(2)
3724(2)
3372(2)
3333(2)
3766(3)
4692(2)
5926(2)
6704(2)
7192(2)
6910(2)
6141(2)
5641(2)
7415(3)
3977(2)
3207(2)
4747(2)
3844(1)
4016(8)
3771(15)
3560(1)
3477(2)
5494(1)
8087(2)
101(2)
56(1)
53(1)
50(1)
50(1)
53(1)
57(1)
70(1)
62(1)
79(1)
97(1)
105(1)
103(1)
79(1)
179(3)
61(1)
61(1)
69(1)
80(1)
78(1)
87(1)
80(1)
107(1)
66(1)
57(1)
64(1)
65(1)
65(1)
81(1)
73(1)
89(1)
87(1)
78(1)
69(1)
71(1)
211(9)
147(11)
66(1)
140(1)
71(1)
119(1)
55(1)
56(1)
56(1)
57(1)
55(1)
56(1)
68(1)
63(1)
C(9B)
6737(3)
5839(2)
6494(2)
6521(3)
5875(3)
5230(2)
7208(4)
1397(2)
911(2)
-1270(2)
-1772(2)
-2060(2)
-1855(2)
-1361(2)
-2580(3)
-719(2)
-1570(2)
-1983(2)
-2564(2)
-2737(2)
-2325(3)
-1743(2)
-3350(2)
2097(2)
2959(2)
3039(2)
3737(2)
4392(2)
4314(2)
3608(2)
5136(3)
1497(2)
-1324(2)
1010(2)
-588(1)
-2826(3)
-980(1)
-3518(2)
2228(1)
5231(2)
337(2)
78(1)
90(1)
93(1)
98(1)
79(1)
136(2)
68(1)
62(1)
81(1)
90(1)
74(1)
98(1)
97(1)
102(1)
67(1)
62(1)
79(1)
84(1)
78(1)
80(1)
71(1)
104(1)
80(1)
84(1)
85(1)
69(1)
192(2)
75(1)
152(1)
71(1)
136(1)
62(1)
57(1)
57(1)
61(1)
64(1)
66(1)
78(1)
74(1)
114(2)
120(2)
87(1)
135(2)
131(2)
118(2)
67(1)
67(1)
81(1)
C(10B)
C(11B)
C(12B)
C(13B)
C(14B)
C(15B)
C(16B)
C(17B)
C(18B)
C(19B)
C(20B)
C(21B)
C(22B)
C(23B)
C(24B)
C(25B)
C(26B)
C(27B)
C(28B)
C(29B)
C(30B)
C(31B)
C(32B)
C(33B)
O(1B)
7048(4)
7990(4)
8625(3)
8330(3)
8341(5)
6772(2)
6198(2)
7074(2)
7164(3)
6405(3)
5543(3)
5426(3)
6539(4)
5544(2)
6387(2)
7258(3)
7321(3)
6506(3)
5637(3)
5563(2)
6553(4)
5654(3)
6838(3)
5911(3)
7185(1)
7909(4)
6019(1)
5944(3)
6417(1)
7297(3)
1079(2)
1221(2)
1024(2)
603(2)
381(2)
-133(2)
-138(2)
386(3)
917(3)
-716(3)
2435(2)
1868(2)
1622(2)
1281(2)
1190(2)
1458(2)
1792(2)
796(3)
4139(2)
3084(3)
1085(2)
4521(1)
7761(3)
1446(1)
-828(3)
2175(1)
480(2)
O(2B)
O(3B)
1520(2)
569(3)
O(4B)
O(5B)
3779(3)
5979(2)
3353(2)
5835(1)
7529(17)
8138(15)
4389(1)
4038(3)
2927(1)
678(2)
O(6B)
C(1C)
-1534(2)
-763(2)
-61(2)
C(2C)
-35(2)
C(3C)
430(2)
C(4C)
-109(2)
-871(2)
-1594(2)
-2326(2)
-3310(2)
-3810(3)
-4559(3)
-4817(2)
-4333(3)
-3576(3)
-5613(3)
729(2)
1270(2)
1631(2)
1173(2)
-156(2)
-592(2)
-960(3)
-1311(3)
-1313(2)
-903(4)
-552(3)
-1718(3)
47(2)
C(5C)
399(2)
C(6C)
658(2)
C(7C)
1450(2)
892(2)
C(8C)
C(9C)
1787(3)
1912(3)
1183(3)
286(3)
3590(2)
2923(2)
2105(2)
1955(2)
2618(2)
3440(2)
4470(2)
5206(2)
C(10C)
C(11C)
C(12C)
C(13C)
C(14C)
C(15C)
C(16C)
C(17C)
C(2B)
-428(2)
-134(2)
691(2)
C(3B)
C(4B)
136(3)
C(5B)
1217(2)
921(2)
1371(4)
1335(2)
2538(2)
2344(3)
C(6B)
C(7B)
-237(2)
1380(2)
52(2)
C(8B)
-1065(2)
2040(2)
-434(2)
123

J Chem Crystallogr (2012) 42:165–172
171
and thermal parameters of the non-hyrdrogen atoms of the
Table 4 continued
2 are listed in Table 4.
x
y
z
U(eq)
C(18C)
C(19C)
C(20C)
C(21C)
C(22C)
C(23C)
C(24C)
C(25C)
C(26C)
C(27C)
C(28C)
C(29C)
C(30C)
C(31C)
C(32C)
C(33C)
O(1C)
2842(3)
3508(3)
3672(3)
3197(3)
4057(3)
-53(2)
504(2)
2673(2)
2629(2)
1971(2)
1354(2)
3273(3)
-923(3)
-600(2)
-284(2)
214(3)
91(1)
78(1)
90(1)
88(1)
105(1)
80(1)
72(1)
74(1)
78(1)
76(1)
92(1)
90(1)
107(1)
81(1)
85(1)
101(1)
82(1)
176(2)
76(1)
133(1)
89(1)
149(1)
Conclusions
379(3)
In summary, 1,3,5-tris(bromomethyl)-2,4,6-trimethylbenzene
and 2,4,6-trimethyl-1,3,5-tris(4-oxymethyl-1-formylphenyl)
benzenehavebeensuccessfully synthesized andcharacterized.
The 3D network structure of 2 is stabilized by the C–HꢀꢀꢀO
hydrogen bonding interactions. The title compound 2 has an
unusual Z0 value of 3. This compound could be used as a
supramolecular synthon to construct polynucleating ligands by
exploiting the reactivity of the benzaldehyde moiety.
-481(3)
2526(2)
3601(2)
4173(2)
4962(2)
5199(2)
4612(3)
3822(2)
6064(3)
-933(2)
1764(2)
1564(3)
-229(2)
-1214(2)
-898(2)
-903(2)
-1213(2)
-1532(3)
-1526(3)
-1212(3)
-684(2)
653(2)
-395(2)
-511(3)
238(3)
1138(3)
1274(3)
36(4)
Supplementary Material
1569(2)
386(3)
495(3)
674(2)
776(3)
2131(2)
4032(3)
717(2)
615(3)
CCDC #765840 and CCDC # 708245 contain the supple-
mentary crystallographic data for this article. This data can
be obtained free of charge at http://www.ccdc.cam.ac.uk/
data_request/cif [or from the Cambridge Crystallographic
Data Centre (CCDC), 12 Union Road, Cambridge CB2
1EZ, UK; Fax: ?44(0)1223-336033; email: deposit@ccdc.
cam.ac.uk].
-2429(2)
-2554(1)
-5887(3)
719(1)
O(2C)
-1747(3)
243(2)
O(3C)
O(4C)
3849(2)
-911(2)
2799(1)
6329(2)
O(5C)
-1222(2)
-1525(3)
O(6C)
Equivalent isotropic Ueq defined as one-third of the trace of the
orthogonalized Uij tensor
Acknowledgments This research work was carried out with the
financial support from the Department of Science and Technology
(DST), Government of India, New Delhi. We thank Dr. Babu Var-
ghese, Sophisticated Analytical Instrumentation Facility (SAIF), IIT
Madras, Chennai, for his help in solving the crystal structures. Thanks
are due to Dr. M. S. Moni, SAIF, IIT Madras, Chennai, for recording
the NMR spectra and to the SAIF, CDRI, Lucknow, for recording the
mass spectra.
molecules are crystallographically and conformationally
nonequivalent. The spacial orientations of the three
p-oxybenzaldehyde moieties with respect to the core differ
within the molecule and among the molecules. One of the
aldehyde oxygens of molecule A is disordered. The C–Br
˚
bond length in 1 is 1.958 A and the C–O bond, formed by
replacing the bromine atom in 1 by p-oxybenzaldehyde
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˚
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There has been significant interest in structures with
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˚
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123

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123