Spectroscopic studies and crystal structure of 1-[(2,5-dioxopyrrolidin-1- yl)(phenyl) methyl] thiourea

Article abstract of DOI:10.1007/s10870-009-9538-8

A new mannich base 1-[(2,5-dioxopyrrolidin-1-yl)(phenyl)methyl] thiourea formed by the direct condensation of thiourea, succinimide and benzaldehyde has been synthesized. The structure of this mannich base has been elucidated on the basis of micro element

Full text of DOI:10.1007/s10870-009-9538-8

J Chem Crystallogr (2009) 39:650–654
DOI 10.1007/s10870-009-9538-8
ORIGINAL PAPER
Spectroscopic Studies and Crystal Structure
of 1-[(2,5-dioxopyrrolidin-1-yl)(phenyl) methyl] Thiourea
S. Rajeswari Æ G. Venkatesa Prabhu Æ
D. Tamilvendan Æ V. Ramkumar
Received: 20 September 2008 / Accepted: 2 March 2009 / Published online: 20 March 2009
Ó Springer Science+Business Media, LLC 2009
Abstract A new mannich base 1-[(2,5-dioxopyrrolidin-1-
yl)(phenyl)methyl] thiourea formed by the direct conden-
sation of thiourea, succinimide and benzaldehyde has been
synthesized. The structure of this mannich base has been
elucidated on the basis of micro elemental analysis, IR, 1H
NMR, 13C NMR, Mass and UV–Visible Techniques. The
crystal structure of the title compound C12 H13 N3 O2 S was
determined. It crystallizes in the monoclinic system, space
tuberculostatic agents) and plant production agents and
pesticides (e.g., chloromethiuron, diafenthiuron, thiopha-
nate and thiophanate-methyl [1, 2]). Thiourea is mainly used
to produce thiourea dioxide. It is widely used in medicine
(sulfathiazole, methyl thiouracil, niridazole and fluoroura-
cil). Thioureas have been suggested as possible pesticides,
herbicides [3], fungicides [4, 5], insecticides, acaricides,
antimalarials [6], antidepressants [7], anti-HIV agents [8],
antiparkinsonian agents [9] and anticorrosive agents [10].
Thioureas also find a wide variety of applications in ana-
lytical chemistry [11]. Thiourea is a common sulfur source
for making the semiconductor cadmium sulfide nano parti-
cle. Thiourea reduces peroxides to the corresponding diols
[12]. It is also used in the reductive workup of ozonolysis to
give carbonyl compounds [13]. It is commonly employed to
convert alkyl halides to thiols. Such reactions proceed via
the intermediacy of isothiuronium salts [14]. Thioureas are
also used as building blocks to pyrimidine derivatives. Thus
thioureas condense with b-dicarbonyl compounds [15].
Several derivatives of thiourea are useful in the treatment of
leprosy. A search through the literature firmly revealed that
no work has been carried out on the synthesis of Mannich
bases employing thiourea, succinimide and benzaldehyde as
the reactants for condensation. Therefore it was thought
worthwhile to synthesize this condensation product through
Mannich condensation reaction involving these compounds
and investigate its molecular structure. Mannich reaction is a
three component condensation reaction consisting of a
compound with active hydrogen, an aldehyde (generally
formaldehyde) and a secondary amine [16, 17]. In continu-
ation with our earlier reported work on the synthesis of 1-
[(2,5-dioxopyrrolidin-1-yl)(phenyl)methyl] urea using urea,
succinimide and benzaldehyde [18], we herein report the
synthesis, spectroscopic studies and crystal structure of the
title compound (Fig. 1).
˚
group P21/c with a = 10.8234 (7) A, b = 6.0355 (5) A,
˚
˚
c = 19.3692 (14) A, b = 100.540(3)°, Z = 4 and V =
3
˚
1243.94 (16) A . The structure was solved by the full-matrix
least squares on F2 and had a refined R value of 0.0465 for
1,964 observed reflections. The crystal structure is stabilized
by strong intramolecular C–HÁÁÁO, C–HÁÁÁS interactions and
inter molecular N–HÁÁÁO and SÁÁÁS interactions.
Keywords Mannich base Á Spectroscopy Á
Crystal structure Á Monoclinic Á
1-[(2,5-dioxopyrrolidin-1-yl)(phenyl) methyl] thiourea
Introduction
Thiourea has a wide range of uses. For example it is used in
the production and modification of textile and dyeing aux-
iliaries, in the leaching of ores, in the production of
pharmaceuticals (antiseptic, thyrotherapeutic, narcotic and
S. Rajeswari Á G. Venkatesa Prabhu Á D. Tamilvendan
Department of Chemistry, National Institute of Technology,
Tiruchirappalli 620015, Tamilnadu, India
V. Ramkumar (&)
Department of Chemistry, Indian Institute of Technology,
Chennai 600036, Tamilnadu, India
e-mail: vramkumar@iitm.ac.in
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J Chem Crystallogr (2009) 39:650–654
651
Fig. 1 The Mannich reaction
scheme
Experimental
data frames. Data reduction was carried out using the
program SAINT-NT [20]. The crystal structure was solved
by direct methods using SHELXTL [21]. Non-hydrogen
atoms were first refined isotropically followed by aniso-
tropic refinement by full matrix least-squares calculations
based on F2 using SHELXTL. Hydrogen atoms were first
located in the difference map then positioned geometrically
and allowed to ride on their respective parent atoms. All
the H atoms except those of nitrogen atoms were geo-
metrically fixed at chemically meaningful positions. The
hydrogen atoms of the phenyl ring were allowed to ride at a
Reagents and Techniques
All the reagents used for synthesizing the title compound
were of A. R Grade and the solvents used were commercial
products of the highest available purity. The micro ele-
mental analysis was carried out with a Carlo Erba 1108
Elemental Analyzer. Infrared spectrum was recorded in
KBr medium on a Spectrum-One Perkin Elmer FTIR
instrument. UV–Visible spectrum was recorded in DMF on
´
1
˚
distance of 0.93 A from the parent carbons and thermal
a EZ301 Perkin Elmer spectrophotometer. H NMR spec-
trum was recorded in CDCl3 and 13C NMR spectrum was
recorded in DMSO-d6 using Bruker AMX-400. FAB Mass
spectrum was recorded on a JEOL SX 102 Mass
Spectrometer.
parameter were fixed at 1.2 times that of the parent atom.
The secondary CH2 hydrogen were fixed at a distance of
˚
0.97 A from the parent atom and their thermal parameters
´
were fixed at 1.2 times of the parent atom. The H atoms
associated with nitrogen atoms were located from the dif-
ference Fourier map and refined isotropically. Diagrams
and publication material were generated using SHELXTL,
PLATON [22] and ORTEP-3 [23]. Details of the data
collection are given in Table 1. The atomic coordinates are
given in Table 2. Selected bond distances and bond angles
are listed in Table 3. Table 4 lists the hydrogen bonds. The
molecular structure with the atom numbering scheme is
shown in Fig. 2. The N–HÁÁÁO and SÁÁÁS interactions are
shown in Fig. 3. Crystallographic data for the structure
reported in this paper has been deposited with the Cam-
bridge Crystallographic Data Centre as supplementary
publication No. CCDC 702350.
Synthesis
Thiourea (15.2 g, 0.2 M), succinimide (19.8 g, 0.2 M) and
benzaldehyde (22 ml, 0.2 M) were taken in equimolar
ratio. To the aqueous concentrated solution of thiourea and
succinimide, benzaldehyde was added in drops with con-
tinous stirring of the solution. The mixture first became
oily and slowly turned into a white crystalline mass. The
organic product was soluble in DMF and DMSO, partially
soluble in acetone, chloroform, carbon tetrachloride, etha-
nol and benzene, insoluble in water. The product was
separated by suction filtration and washed several times
with distilled water. It was dried in the air oven at 80 °C
and was recrystallised from acetone by slow evaporation.
Colorless crystals suitable for X-ray diffraction study were
obtained, m.p. = 196–198 °C, yield 85.4%. Found: C,
53.5; H, 4.75; N, 15.11. Calc. For C12 H13 N3 O2 S; C,
54.75; H, 4.94; N, 15.97%.
Results and Discussion
1
IR, H NMR, 13C NMR, UV–Visible and Mass
The title compound shows a number of IR absorption
bands and the absorption frequencies are in a slightly
shifted position in comparison with those of the reactants,
thiourea and succinimide. This favorably indicates the
substitution on succinimide and thiourea and the formation
of a new compound. The asymmetric and symmetric m NH2
Crystallography
A crystal of dimensions 0.20 9 0.19 9 0.15 mm was used
for collection of intensity data on a ‘‘Bruker APEXII
CCD’’ area detector diffractometer with graphite mono-
chromated MoKa radiation (50 kV, 30 mA) using the
APEX2 [19] data collection software. The collection
method involved x-scans of width 0.5° and 512 9 512 bit
and m stretching vibration of the title compound occurs
NH
at 3,399, 3,312 and 3,195 cm-1. The asymmetric and
symmetric stretching vibration of mCH2 occurs at 3,033 and
123

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J Chem Crystallogr (2009) 39:650–654
Table 2 Atomic coordinates (9104) and equivalent isotropic dis-
placement parameters (A2 9 103) for 1-[(2,5-dioxopyrrolidin-1-
yl)(phenyl) methyl] thiourea. U(eq) is defined as one-third of the trace
of the orthogonalized Uij tensor
Table 1 The Crystal structure data for 1-[(2,5-dioxopyrrolidin-1-yl)
(phenyl) methyl] thiourea
CCDC No.
702350
Empirical formula
Formula weight
Temperature
C12 H13 N3 O2 S
263.31
x
y
z
U(eq)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
C(10)
C(11)
C(12)
N(1)
N(2)
N(3)
O(1)
O(2)
S(1)
5,310(2)
3,986(2)
3,742(2)
4,918(2)
7,096(2)
7,761(2)
7,751(3)
8,414(3)
9,088(3)
9,112(2)
9,322(4)
8,103(2)
5,796(2)
7,137(2)
8,154(2)
5,892(2)
5,127(2)
9,137(1)
4,370(4)
4,089(5)
6,104(5)
7,473(4)
6,987(4)
7,419(4)
5,786(5)
6,070(6)
7,974(5)
9,601(5)
8,103(2)
9,092(4)
6,297(3)
8,814(4)
923(1)
35(1)
47(1)
45(1)
36(1)
29(1)
31(1)
43(1)
52(1)
48(1)
48(1)
38(1)
29(1)
29(1)
32(1)
41(1)
48(1)
55(1)
40(1)
298(2) K
´
˚
1,041(2)
1,465(2)
1,550(1)
1,271(1)
2,022(1)
2,523(1)
3,197(1)
3,380(1)
2,887(1)
2,206(1)
444(1)
Wavelength
0.71073 A
Crystal system, space group
Unit cell dimensions
Monoclinic, P21/c
´
˚
a = 10.8234(7) A a = 90°
´
˚
b = 6.0355(5) A b = 100.540(3)°
´
˚
c = 19.3692(14) A c = 90°
Volume
1243.94(16) A3
4, 1.406 Mg/m3
0.258 mm-1
Z, Calculated density
Absorption coefficient
F(000)
552
Crystal size
0.20 9 0.19 9 0.15 mm
Theta range for data collection 1.91–28.32°
Limiting indices
1,247(1)
796(1)
-14 B h B 14, -5 B k B 8,
-25 B l B 24
Reflections collected/unique
Diffractometer, scan mode
9308/2875 [R(int) = 0.0387]
11,057(4)
3,142(3)
9,266(3)
7,064(1)
140(1)
Bruker Apex II CCD, Omega
and Phi
603(1)
1,813(1)
377(1)
Absorption correction
Max. and min. transmission
Refinement method
Multi-scan
0.9623 and 0.9502
Full-matrix least-squares on F2
2875/0/175
˚
Data/restraints/parameters
Goodness-of-fit on F2
Table 3 Selected bond lengths (A) and angles (°) for 1-[(2,5-di-
oxopyrrolidin-1-yl)(phenyl) methyl] thiourea
0.853
Final R indices [I [ 2sigma(I)] R1 = 0.0465, wR2 = 0.1239
R indices (all data) R1 = 0.0760, wR2 = 0.1573
Largest different peak and hole 0.481 and -0.253 e.A-3
C(1)–O(1)
1.215(3)
1.379(3)
1.502(4)
1.517(4)
1.502(4)
1.200(3)
1.397(3)
1.442(3)
1.461(3)
1.523(3)
1.331(3)
1.359(3)
1.680(2)
124.5(2)
116.4(18)
118(2)
N(1)–C(4)–C(3)
N(2)–C(5)–N(1)
N(2)–C(5)–C(6)
N(1)–C(5)–C(6)
N(2)–C(5)–H(5)
N(1)–C(5)–H(5)
C(11)–C(6)–C(7)
C(11)–C(6)–C(5)
N(3)–C(12)–N(2)
N(3)–C(12)–S(1)
N(2)–C(12)–S(1)
C(1)–N(1)–C(4)
C(1)–N(1)–C(5)
C(12)–N(2)–C(5)
C(5)–N(2)–H(2)
C(12)–N(3)–H(4)
107.6(2)
109.85(18)
114.49(19)
111.32(17)
106.9
C(1)–N(1)
C(1)–C(2)
C(2)–C(3)
C(3)–C(4)
2,929 cm-1. The m
stretching vibration of the amide
C(4)–O(2)
106.9
C=O
occurs at 1,694 cm-1. The m C=S stretching vibration occurs
C(4)–N(1)
119.0(2)
121.9(2)
115.5(2)
122.19(19)
122.27(18)
112.8(2)
122.67(19)
122.0(2)
118.6(18)
121(2)
at 1,449 cm-1. The d NH in plane bending and out of plane
C(5)–N(2)
bending occurs at 1,540 and 729 cm-1. The m
C(5)–N(1)
C–N–C
stretching vibration occurs at 1,178 cm-1. The aromatic
C(5)–C(6)
monosubstituted vibration occurs at 694 cm-1
.
C(12)–N(3)
C(12)–N(2)
C(12)–S(1)
C(4)–N(1)–C(5)
C(12)–N(2)–H(2)
C(12)–N(3)–H(3)
The 1H NMR data for the title compound in CDCl3
reveal the aromatic protons as multiplets at d 7.2–8.0 ppm.
The NH2 protons appear at d 10.0 ppm. The signal at d
8.61 ppm is due to the NH proton. The CH2 protons of
succinimide appear as a multiplet at d 2.72 ppm whereas
the methine CH proton appears at d 2.55 ppm. The signals
of the CH2 protons of succinimide are shifted upfield on
substitution.
The 13C NMR data for the title compound in DMSO-d6
shows that the signals for the aromatic carbon atoms appear
as a multiplet at d 137.3–125.7 ppm. The signal for the
C=S carbon of thiourea appears at d 183.3 ppm while the
signal for the C=O carbon of succinimide is at d 179.4,
177.1 ppm. The doublet signal for the CH2 carbon of
succinimide and the CH carbon appear at d 29.5 and d
62.5 ppm, respectively.
Saturated compounds containing heteroatoms such as
nitrogen, oxygen etc., have non-bonding electrons in
addition to r electrons. The UV spectrum of the title
compound in DMF solution registers intense split bands
centered at 280 and 264 nm which is presumably due to
123

J Chem Crystallogr (2009) 39:650–654
653
n ? p* transition of the carbonyl group and p ? p*
transition of the carbonyl and the aromatic ring.
Table 4 List of (a) intermolecular and (b) intramolecular Hydrogen
Bonds
The FAB Mass spectrum shows a weak molecular ion
peak at m/z 263 which confirms the assigned molecular
mass for the title compound. Thereupon on fragmentation it
records intense signals at m/z 203, m/z 188, m/z 98 and m/z
90 which are due to C11H11O2N?2 ., C11 H10O2 N?,
C4H4O2 N? and C7 H6?, respectively.
Donor–HÁÁÁAcceptor
D–H
HÁÁÁA
DÁÁÁA
D–HÁÁÁA
Intermolecular
N(2)–H(2)ÁÁÁO(1)a
N(3)–H(3)ÁÁÁS(1)b
N(3)–H(4)ÁÁÁO(1)a
C(2)–H(2A)ÁÁÁO(2)c
Intramolecular
0.85(3) 2.13(3)
0.85(3) 2.62(3)
0.80(4) 2.34(3)
0.97(3) 2.58(2)
2.931(3) 158(2)
3.458(2) 169(3)
3.031(3) 146(3)
3.400(4) 142(3)
C(5)–H(5)ÁÁÁS(1)
C(5)–H(5)ÁÁÁO(1)
C(11)–H(11)ÁÁÁN(2)
0.98(3) 2.55(2)
0.98(2) 2.43(3)
0.93(3) 2.51(3)
3.047(2) 112(3)
2.854(3) 106(4)
2.855(3) 102(4)
Crystallographic Study
Single crystal X-ray diffraction study of the title compound
showed that it crystallized in the monoclinic system with
P21/c space group.
Symmetry: a = x, 1 ? y, z; b = -x, 1-y, 1-z; c = x, -1 ? y, z
The title compound contains two ring systems, viz
succinimido ring and the phenyl ring which are linked
through the thiourea moiety. The title compound is anal-
ogous to the molecule C12H13N3O3 which we have
reported in [18] which has the same conformation but the
intra and inter molecular interactions are different. In the
crystal structure of C12H13N3O3, the molecules related
through center of inversion are linked to each other through
˚
N3–H3ÁÁÁO3 hydrogen bonds (2.363 (11) A, 155.1(15)°)
forming a dimeric pair. In the title compound there is a
strong intermolecular hydrogen bonding N3–H3–S1 =
˚
3.458 (2) A, N3–H4–O1 = 3.031 (3) A and there is S–S
˚
˚
interaction of 3.58 A [24]. The C=S distance [C(12)–
˚
S(1) = 1.680 (2) A] for the thiourea moiety in the title
˚
compound is slightly shorter than the mean value (1.681 A
Fig. 2 The crystal structure of the title compound
[25]) for the thioureas, the C–N bond distance [C(12)–
˚
N(2) = 1.359 (3) A] is slightly increased to the extent of
o
0.02A (1.33 (2) A) with reference to the literature value
˚
[26] of thiourea. The other C–N bond distance [C(12)–
˚
N(3) = 1.331 (3) A] agrees well with the literature value
for the C–N bond distance in thiourea. Generally upon N-
substitution, the bond order of C–S is found to be reduced
while that of C–N is slightly increased. Another reason for
the shortening of the C–S bond can be attributed to the
presence of intramolecular hydrogen bonding [C(5)–
˚
H(5)ÁÁÁS(1) = 2.55 A]. The C12–N2 (imino) bond in the
˚
title compound is 0.028 A longer than the C12–N3 (amino)
bond. Significant difference between the C–N (amino) and
C–N (imino) bonds also exist in fluorophenylthiourea
˚
(0.026 (3) A) [27], chlorophenylthiourea (0.022 (4) A)
˚
˚
[28], bromophenylthiourea (0.024 (4) A) [29]. The N(3)–
C(12)–N(2) angle is 115.5(2)° which is relatively less in
comparison with the N(2)–C(1)–N(1) angle of 117.93(15)°
for phenylthiourea [30]. There is a strong intermolecular
hydrogen bonding between O1 atom of succinimide with
the N2 and N3 atoms of thiourea [O(1)–N(2) = 2.932
˚
˚
(3) A; O (1)–N (3) = 3.031(3) A] while the NÁÁÁH distance
˚
is 0.85(3) and 0.80 (4) A, respectively. The O1–N2 and
Fig. 3 The packing diagram showing S–S and N–HÁÁÁO interactions
123

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J Chem Crystallogr (2009) 39:650–654
˚
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˚
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˚
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˚
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˚
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˚
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˚
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˚
(3) A] is exactly in accordance with the theoretical value.
˚
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compound is shorter than the C=O bond distances 1.24 and
˚
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between the succinimide moiety and the phenyl ring is
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is 114.49(19)° and the dihedral angle N2–C5–N1 is
109.85(18)°. The torsional angles C1–N1–C5–N2, C4–N1–
C5–N2 linking the succinimide, phenyl and thiourea moi-
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C5–N2 and C11–C6–C5–N2 angles are 178.5(2)° and
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Acknowledgments The first author wishes to acknowledge the
Department of Chemistry, Indian Institute of Technology, Chennai for
the single crystal XRD analysis, Regional Sophisticated Instrument
Facility, Central drug Research Institute, Lucknow, India for
recording the CHN values and Mass spectrum, Indian Institute of
Science, Bangalore for recording the NMR and Technical Education
Quality Improvement Program (TEQIP), of Government of India for
the financial assistance.
References
1. Concise International chemical Assessment Document 49, World
Health Organisation, Geneva 2003
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