Spectroscopic studies and crystal structure of 1-(morpholino (phenyl) methyl) pyrrolidine-2,5-dione

Article abstract of DOI:10.1007/s10870-009-9674-1

A new mannich base 1-(morpholino(phenyl)methyl)pyrrolidine-2,5-dione formed by the direct condensation of morpholine, 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, UV-Visible Techniques and Mass. The crystal structure of the title compound C₁₅ H₁₈ N₂ O₃ was determined. It crystallizes in the triclinic system, space group P - 1, with a = 8.8122(13) A, b = 9.2794(14) A, c = 9.814 (3) A, α = 107.154(9)°, β = 97.936(9)°, γ = 110.197(7)°,V = 693.4(2) A³, D _x = 1.314 Mg/m³. The structure was solved by the full-matrix least squares on F² and had a refined R value of 0.0486 for 8567 observed reflections. The six membered heterocyclic ring of the morpholino moiety adopts a chair conformation. The crystal structure is stabilized by weak intermolecular C-H???O interactions that link the molecules into inversion dimers.

Full text of DOI:10.1007/s10870-009-9674-1

J Chem Crystallogr (2010) 40:437–442
DOI 10.1007/s10870-009-9674-1
ORIGINAL PAPER
Spectroscopic Studies and Crystal Structure of 1-(Morpholino
(Phenyl) Methyl) Pyrrolidine-2,5-Dione
•
S. Rajeswari G. Venkatesa Prabhu
•
•
D. Tamilvendan V. Ramkumar
Received: 31 October 2008 / Accepted: 24 December 2009 / Published online: 19 January 2010
Ó Springer Science+Business Media, LLC 2010
Abstract A new mannich base 1-(morpholino(phenyl)
methyl)pyrrolidine-2,5-dione formed by the direct conden-
sation of morpholine, 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, UV–Visible Techniques and Mass. The
crystal structure of the title compound C15 H18 N2 O3 was
determined. Itcrystallizesin the triclinic system, space group
important use is as a chemical intermediate in the prepa-
ration of pesticides [1]. Morpholine has many important
applications. It is used as an intermediate in the manufac-
ture of rubber chemicals and optical brighteners. It is also
used extensively as a corrosion inhibitor in steam boiler
systems. Fatty acid derivatives of morpholine are used as
emulsifiers in the manufacture of waxes and polishes.
Drugs containing a morpholine ring have established
activities that include the reduction of blood sugar and lipid
levels [2] and amelioration of obesity and insulin resistance
[3]. The physiological activity of the morpholine nucleus is
attested by the number of pharmaceutical applications
which have been found for it. The hydroperiodide is suit-
able for incorporation in ointments for the treatment of skin
disorders, such as athlete’s foot. A number of morpholine
derivatives have been described as analgesics and local
anesthetics. Several morpholine-derived chemicals are
useful as respiratory and vasomotor stimulants. Other
pharmaceutical fields in which morpholine has found
application include choleretics, antispasmodics, analeptics,
and antimalarials. In addition, the use of morpholine as a
peptizing agent for preparing aqueous dispersions of phe-
nothiazines for anthelmintic purposes has been claimed.
Owing to their pharmacological activities these com-
pounds have received a great deal of attention in respect of
their synthesis and conformation. A number of morpholine
derivatives have been shown to possess bactericidal
activity. For example, morpholinium salts of certain acyl-
ated sulfonamides possess strong bacteriostatic or bacteri-
cidal properties, and morpholine hydroperiodide has been
used as a water disinfectant. The reaction of morpholine
˚
P - 1, with a = 8.8122(13) A, b = 9.2794(14) A, c = 9.814
˚
˚
(3) A, a = 107.154(9)°, b = 97.936(9)°, c = 110.197(7)°,
3
3
˚
V = 693.4(2) A , Dx = 1.314 Mg/m . The structure was
solved by the full-matrix least squares on F2 and had a refined
R value of 0.0486 for 8567 observed reflections. The six
membered heterocyclic ring of the morpholino moiety
adopts a chair conformation. The crystal structure is stabi-
lized by weak intermolecular C–HÁÁÁO interactions that link
the molecules into inversion dimers.
Keywords Mannich base Á Spectroscopy Á Crystal
structure Á Triclinic 1-(morpholino(phenyl)methyl)
pyrrolidine-2,5-dione
Introduction
Morpholine is a multipurpose chemical which is used as a
solvent for resins, dyes and waxes. One of its most
S. Rajeswari Á G. V. Prabhu Á D. Tamilvendan
Department of Chemistry, National Institute of Technology,
Tiruchirappalli, Tamilnadu 620 015, India
with 3,4,5-trichloro-2,6-pyridinedicarbonitrile yields
a
V. Ramkumar (&)
product which is useful in the control of fungi. Morpholine
is used in preparing compounds that are excellent herbi-
cides and that can be applied either to the soil before the
Department of Chemistry, Indian Institute of Technology,
Chennai, Tamilnadu 600 036, India
e-mail: vramkumar@iitm.ac.in
123

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J Chem Crystallogr (2010) 40:437–442
weeds emerge or to the growing plants. The morpholi-
nomethyl derivative of pyrizinamide (morphozinamide)
has been found to be more effective in the treatment of
tuberculosis than pyrizinamide [4].
Experimental
Reagents and Techniques
Succinimide is a diketopyrrolidine that is prepared by
heating succinic anhydride with aqueous ammonia, fol-
lowed by rapid distillation of ammonium succinate [5, 6].
Succinimide and other cyclic carboximides are used as
starting materials in organic synthesis. Their nitranions are
also important intermediates in many chemical reactions
[5–8]. Derivatives of succinimide are of important bio-
logical and pharmacological interest. In addition, succini-
mide itself is a hypooxaluric agent [9]. Succinimide
oxidises in various substrates in different media [10–15].
Extensive work has been reported on the kinetics of oxi-
dation of amino acids and peptides with various metal ions
and several other oxidants [15–17]. The comparative
studies on the kinetics of oxidation of amino acids and
tetrapeptides by N-bromosuccinimide have been reported
[18]. The crystal structures of several succinimide deriva-
tives have been reported with respect to their biological
properties, e.g. antiepileptic and anticonvulsive [19–22],
fungicidal [19] and other pharmacological [23] activities.
In each of these compounds, the ring nitrogen is substituted
either by methyl group, or differently substituted phenyl
and pyridine rings or morpholinomethyl moiety [24]. The
succinimide derivatives are useful as anti-anxiety drugs.
A group of phenylsuccinimides [25, 26] proved to have
strong anticonvulsive activity. A search through the litera-
ture firmly revealed that no work has been carried out on the
synthesis of Mannich bases employing succinimide, mor-
pholine and benzaldehyde as the reactants for condensation.
Therefore it was thought worthwhile to synthesize this
condensation product through Mannich condensation reac-
tion and investigate its molecular structure. Mannich reac-
tion is a three component condensation reaction consisting
of a compound with active hydrogen, an aldehyde (gener-
ally formaldehyde) and a secondary amine [27, 28]. In
continuation with the earlier reported work on the synthesis
of 1-[(2,5-dioxopyrrolidin-1-yl)(phenyl)methyl] urea using
urea, succinimide and benzaldehyde [29], we herein report
the synthesis, spectroscopic studies and crystal structure of
the title compound (Fig. 1).
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
1
instrument. H NMR spectrum was recorded in DMSO-d6
and 13C NMR spectrum was recorded in CDCl3 using a
Bruker 300 MHz instrument. UV–Visible spectrum was
recorded in DMF on a EZ301 Perkin Elmer spectropho-
tometer. FAB Mass spectrum was recorded on a JEOL SX
102 Mass Spectrometer.
Synthesis
Succinimide (19.8 g, 0.2 M), morpholine (18 mL, 0.2 M)
and benzaldehyde (22 mL, 0.2 M) were taken in equimolar
ratio. Morpholine was added slowly to succinimide taken
in a 250 mL beaker. Sufficient amount of ethanol was
added to make the contents a homogeneous solution.
Benzaldehyde was added slowly in drops with continuos
stirring of the solution. A yellowish white powdery sub-
stance was formed immediately. After 10 days the product
was washed several times with distilled water. The product
was dried in the air oven at 60 °C and recrystallised from
ethanol by slow evaporation. Colorless crystals suitable for
X-ray diffraction study were obtained m.p. 100–105 °C,
yield 85.4%. Found: C, 63.68; H, 6.52; N, 10.43. Calc. For
C15H18N2O3; C, 65.69; H, 6.57; N, 10.22%.
Crystallography
A crystal of dimensions 0.40 9 0.28 9 0.22 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 [30] data collection software. The collection
method involved phi and x-scans of width 0.5° with an
exposure time of 10 s/frame. Data reduction was carried
out using the program SAINT? [31]. The crystal structure
was solved by direct methods using SHELXTL [32]. Non-
hydrogen atoms were first refined isotropically followed by
anisotropic refinement by full matrix least-squares calcu-
lations 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. Hydrogen atoms involved in hydrogen-bonding
were located in the difference map and refined freely.
Diagrams and publication material were generated using
Fig. 1 The Mannich reaction scheme
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J Chem Crystallogr (2010) 40:437–442
439
Table 1 The crystal structure
data for 1-(morpholino(phenyl)
methyl)pyrrolidine-2,5-dione
CCDC no.
705027
Empirical formula
Formula weight
C15 H18 N2 O3
274.31
Temperature
298(2) K
Wavelength
0.71073 A
Crystal system, space group
Unit cell dimensions
Triclinic, P - 1
a = 8.8122(13) A a = 107.154(9)°
b = 9.2794(14) A b = 97.936(9)°
c = 9.814(3) A c = 110.197(7)°
693.4(2) A3
Volume
Z, Calculated density
Absorption coefficient
F(000)
2, 1.314 Mg/m3
0.092 mm-1
292
Crystal size
0.40 9 0.28 9 0.22 mm
Theta range for data collection
Limiting indices
2.25 to 31.87°
-7 B h B 12, -13 B k B 11, -12 B l B 14
8,567/3,384 [R(int) = 0.0238]
0.9800 and 0.9640
Reflections collected/unique
Max. and min. transmission
Refinement method
Data/restraints/parameters
Goodness-of-fit on F2
Full-matrix least-squares on F2
3,384 / 0 / 182
0.956
Final R indices [I [ 2r (I)] R1 = 0.0483,
wR2 = 0.1493
R indices (all data)
R1 = 0.0889, wR1 = 0.1869
0.008(9)
0.223 and -0.198 e.A-3
Extinction coefficient
Largest diff. peak and hole
SHELXTL, PLATON [33] and ORTEP-3 [34]. 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 chemical diagram of the title com-
pound is given in Fig. 2. The molecular structure with the
atom numbering scheme is shown in Fig. 3. Crystallo-
graphic data for the structure reported in this paper has
been deposited with the Cambridge Crystallographic Data
Centre as supplementary publication No. CCDC 705027.
2,852 cm-1 and the corresponding bending vibration
occurs at 1,421 cm-1 .The mC=O stretching vibration of the
amide occurs at 1,704 cm-1. The mC–N–C and mC–O–C
stretching vibration appears at 1,175 and 1,037 cm-1. The
aromatic monosubstituted vibration occurs at 699 cm-1
.
1
The H NMR data for the title compound in DMSO-d6
reveal the aromatic protons as multiplets at d 7.35 ppm.
The O–CH2 and N–CH2 protons of morpholine appear as a
multiplet at d 3.69 and d 2.66 ppm respectively. The signal
for the CH2 protons of succinimide appear at d 2.76 ppm
while the signal for the methine CH proton appears at d
5.88 ppm. The signals of the CH2 protons of succinimide
are shifted downfield on substitution.
Results and Discussion
The 13C NMR data for the title compound in CDCl3
shows that the signals for the aromatic carbon atoms appear
as a multiplet at d 138 ppm. The signal for the C=O carbon
of succinimide appears at d 178, 177 ppm. The doublet and
triplet signals observed at d 50 and d 67 ppm is due to the
N–CH2 and O–CH2 carbons of morpholine. The doublet
signal for the CH2 carbon of succinimide appears at d
29 ppm while the signal for the CH carbon occurs at d
89 ppm respectively.
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
succinimide and morpholine. This favorably indicates the
substitution on succinimide and morpholine and the for-
mation of a new compound. The aromatic mC–H stretching
vibration appears at 3,091 cm-1. The asymmetric and
Saturated compounds containing heteroatoms such as
nitrogen, oxygen etc, have non-bonding electrons in addition
symmetric stretching vibration of mCH occurs at 2,945 and
2
123

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J Chem Crystallogr (2010) 40:437–442
Table 2 Atomic coordinates (9104) and equivalent isotropic dis-
placement parameters (A2 9 103) for new. U(eq) is defined as one
third of the trace of the orthogonalized Uij tensor
Table 3 Selected bond lengths [A] and angles [°]
C(1)–O(1)
1.210(2)
1.390(2)
1.496(2)
1.505(3)
1.500(3)
1.204(2)
1.395(2)
1.4439(19)
1.4875(19)
1.528(2)
0.9800
C(1)–N(1)
x
y
z
U(eq)
C(1)–C(2)
C(2)–C(3)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
N(1)
N(2)
O(1)
O(2)
O(3)
6,340(2)
4,901(2)
4,973(3)
6,573(2)
8,839(2)
1,496(2)
1,460(2)
561(3)
6,582(2)
7,241(2)
8,282(3)
8,327(2)
6,920(2)
9,492(2)
35(1)
45(1)
58(1)
42(1)
31(1)
44(1)
58(1)
63(1)
46(1)
33(1)
44(1)
51(1)
47(1)
52(1)
44(1)
34(1)
34(1)
46(1)
61(1)
70(1)
C(3)–C(4)
C(4)–O(2)
C(4)–N(1)
316(2)
C(5)–N(2)
786(2)
C(5)–N(1)
10,659(2)
12,449(3)
12,496(3)
10,706(2)
8,808(2)
7,335(2)
7,334(2)
8,766(2)
10,230(2)
10,250(2)
7,290(2)
10,385(2)
6,649(2)
7,149(2)
12,783(2)
2,347(2)
3,563(3)
4,860(2)
3,684(2)
-934(2)
C(5)–C(10)
10,302(2)
8,602(3)
7,750(2)
6,648(2)
5,863(2)
5,528(2)
5,965(2)
6,724(2)
7,056(2)
7,300(2)
7,921(1)
5,579(1)
9,087(2)
10,123(2)
C(5)–H(5)
C(6)–N(2)
1.462(2)
1.513(3)
1.427(3)
1.414(3)
1.513(3)
1.464(2)
1.375(2)
1.389(2)
1.386(3)
0.9300
C(6)–C(7)
C(7)–O(3)
-2,327(2)
-3,887(2)
-4,083(2)
-2,709(2)
-1,145(2)
880(2)
C(8)–O(3)
C(8)–C(9)
C(9)–N(2)
C(10)–C(15)
C(10)–C(11)
C(11)–C(12)
C(11)–H(11)
C(12)–C(13)
C(12)–H(12)
C(13)–C(14)
C(13)–H(13)
C(14)–C(15)
C(14)–H(14)
C(15)–H(15)
O(1)–C(1)–N(1)
O(1)–C(1)–C(2)
N(1)–C(1)–C(2)
C(4)–C(3)–C(2)
O(2)–C(4)–N(1)
O(2)–C(4)–C(3)
N(1)–C(4)–C(3)
N(2)–C(5)–N(1)
N(2)–C(5)–C(10)
N(1)–C(5)–C(10)
N(2)–C(5)–H(5)
N(1)–C(5)–H(5)
C(10)–C(5)–H(5)
N(2)–C(6)–C(7)
O(3)–C(7)–C(6)
O(3)–C(8)–C(9)
N(2)–C(9)–C(8)
C(15)–C(10)–C(11)
C(15)–C(10)–C(5)
C(11)–C(10)–C(5)
C(12)–C(11)–C(10)
C(12)–C(11)–H(11)
2,099(2)
1,955(2)
-279(2)
5,105(2)
1.366(3)
0.9300
1.373(3)
0.9300
to r electrons. The UV spectrum of the title compound in
DMF solution registers intense split bands centered at
280 nm and 264 nm which is presumably due to n ? p*
transition of the carbonyl group and p ? p* transition of
the carbonyl and the aromatic ring.
1.384(2)
0.9300
0.9300
124.19(15)
127.20(16)
108.61(15)
105.84(15)
125.04(17)
127.13(17)
107.82(15)
114.70(13)
113.23(13)
111.10(12)
105.6
The FAB Mass spectrum shows a weak molecular ion
peak at m/z 274 which confirms the assigned molecular
mass for the title compound. Thereupon on fragmentation it
records intense signals at m/z 197, 187, 99, 90, 76 which
?
are due to C9H13N2O3?, C11H10NO2?, C5H9NO?, C7H6
C6H5?, respectively.
,
Crystallographic Study
The title compound C15 H18 N2 O3 crystallizes in the tri-
clinic system with space grouping P-1. The title compound
contains three ring systems, the succinimido ring, the
phenyl ring and the morpholino ring. The phenyl ring is
linked by the succinimido and the morpholino ring. The
C–N bond distances [C(1)–N(1) = 1.390; C(4)–N(1) =
1.395] in the succinimido ring is considerably shorter than
105.6
105.6
108.95(14)
111.00(17)
111.55(17)
108.37(16)
118.45(16)
121.27(14)
120.05(15)
120.06(17)
120.0
˚
the C–N single bond value of 1.47 A as suggested by
˚
Pauling [35]. The C2–C3 distances are 1.505 A. The
C–C distances [C(1)–C(2) = 1.496; C(3)–C(4) = 1.500]
between the carbon atoms adjacent to the carbonyl groups
are found to be shorter than the normal values. The value
of C=O bond distances [C(1)–O(1) = 1.210; C(4)–
123

J Chem Crystallogr (2010) 40:437–442
441
Table 3 continued
C(10)–C(11)–H(11)
C(13)–C(12)–C(11)
C(13)–C(12)–H(12)
C(11)–C(12)–H(12)
C(12)–C(13)–C(14)
C(12)–C(13)–H(13)
C(14)–C(13)–H(13)
C(13)–C(14)–C(15)
C(13)–C(14)–H(14)
C(15)–C(14)–H(14)
C(10)–C(15)–C(14)
C(10)–C(15)–H(15)
C(14)–C(15)–H(15)
C(1)–N(1)–C(4)
120.0
120.99(17)
119.5
119.5
119.18(17)
120.4
120.4
120.36(19)
119.8
119.8
120.94(16)
119.5
119.5
112.12(14)
121.83(13)
125.98(13)
117.40(12)
113.10(14)
109.35(14)
109.78(15)
C(1)–N(1)–C(5)
C(4)–N(1)–C(5)
C(5)–N(2)–C(6)
C(5)–N(2)–C(9)
Fig. 3 The atom numbering scheme
C(6)–N(2)–C(9)
C(8)–O(3)–C(7)
Symmetry transformations used to generate equivalent atoms
Table 4 List of intermolecular hydrogen bonds
Donor-HÁÁÁacceptor
C(2)–H(2B)ÁÁÁO(3)a
Symmetry: a = -x, 1 - y, -z
D–H
HÁÁÁA
DÁÁÁA
D–HÁÁÁA
0.97(3)
2.46(3)
3.194(3)
132(2)
Fig. 2 The chemical diagram of the title compound
O(2) = 1.204] are found to be shorter than the C=O bond
˚
distances 1.24 and 1.26 A found by Mason [36] in
succinimide.
Fig. 4 Packing diagram showing C–HÁÁÁO interaction
In the morpholine ring the C–C distances [C6–C7=C8–
˚
C9] and C–N distances [C6–N2] and [C9–N2] are 1.513 A,
˚
1.462 and 1.464 A respectively. The C–O distances [C7–
agreement with the structural data available from Version
5.14 of the Cambridge Structural Database [38]. The study
of the torsion angle, asymmetry parameters and least
square calculations shows that the six membered morpho-
line ring adopts a chair conformation with a deviation of
˚
O3] and [C8–O3] are 1.427 and 1.414 A respectively. The
C–C, C–N and C–O distances in morpholine are found to
be less than the normal values [C–C = 1.53, C–N = 1.47,
˚
C–O = 1.45 A] reported by Alekseev [37]. This is in
˚
O3 and N2 from the C6/C7/C8/C9 plane by 0.652(2) A and
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J Chem Crystallogr (2010) 40:437–442
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-0 .687(2) A respectively, Q(2) = 0.019(2) A, U = 8(7)°,
˚
QT = 0.587(2) A, h = 178.8(2)° [39]. The sum of the
angles around N1 is 359.93° indicating sp2 hybridization.
The [C1–N1–C5] angle between the succinimide and the
phenyl moiety is 121.83° whereas the [C5–N2–C9] angle
between the phenyl and morpholino moiety is 113.10°. The
angle linking the three units [N1–C5–N2] is 114.70° which
is less compared with the [N1–C5–N2] angle of 116.94° for
1-(Morpholin-4-ylmethyl)pyrrolidine-2,5-dione [40] and
[N1–C9–N2] angle of 116.95° for 2-(Morpholin-4-
ylmethyl)isoindole-1,3-dione [41]. The [N1–C5–N2] angle
for the title compound may be less due to the presence of
the bulky phenyl group linking the other two units.
The torsion angle of N(1)–C(5)–N(2)–C(6) is 55.34°.
The structure is stabilized by weak intermolecular C–HÁÁÁO
interactions that link the molecule into a pair around a
center (Fig. 4).
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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, SASTRA University,
Thanjavur, Tamilnadu, India for recording the NMR spectrum.
28. Tramontini M (1973) Synthesis 12:703. doi:10.1055/s-1973-
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