Synthesis and crystal structure of 1-(2-nitro-benzenesulfonyl)-piperidin-4- yl-diphenyl-methanol

Article abstract of DOI:10.1080/15421400801914988

The title compound 1-(2-nitro-benzenesulfonyl)-piperidin-4-yl-diphenyl- methanol was synthesized by the condensation of [piperidin-4-yl]-diphenyl- methanol with 2-nitro benzene sulfonylchloride in methylene dichloride as solvent and triethylamine as the b

Full text of DOI:10.1080/15421400801914988

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Synthesis and Crystal Structure
of 1-(2-Nitro-benzenesulfonyl)-
piperidin-4-yl-diphenyl-
methanol
S. B. Benaka Prasad a , S. Naveen b , C. S.
Anandakumar a , K. Vinaya a , N. S. Linge Gowda a
, M. A. Sridhar b , J. Shashidhara Prasad b & K. S.
Rangappa a
a Department of Studies in Chemistry , University of
Mysore , Mysore, India
b Department of Studies in Physics , University of
Mysore , Mysore, India
Published online: 22 Sep 2010.
To cite this article: S. B. Benaka Prasad , S. Naveen , C. S. Anandakumar , K. Vinaya ,
N. S. Linge Gowda , M. A. Sridhar , J. Shashidhara Prasad & K. S. Rangappa (2008)
Synthesis and Crystal Structure of 1-(2-Nitro-benzenesulfonyl)-piperidin-4-yl-diphenyl-
methanol, Molecular Crystals and Liquid Crystals, 482:1, 145-154
To link to this article: http://dx.doi.org/10.1080/15421400801914988
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Mol. Cryst. Liq. Cryst., Vol. 482, pp. 145–154, 2008
Copyright # Taylor & Francis Group, LLC
ISSN: 1542-1406 print=1563-5287 online
DOI: 10.1080/15421400801914988
Synthesis and Crystal Structure of 1-(2-Nitro-
benzenesulfonyl)-piperidin-4-yl-diphenyl-methanol
S. B. Benaka Prasad1, S. Naveen2, C. S. Anandakumar1,
K. Vinaya1, N. S. Linge Gowda1, M. A. Sridhar2,
J. Shashidhara Prasad2, and K. S. Rangappa1
1Department of Studies in Chemistry, University of Mysore,
Mysore, India
2Department of Studies in Physics, University of Mysore, Mysore, India
The title compound 1-(2-nitro-benzenesulfonyl)-piperidin-4-yl-diphenyl-methanol
was synthesized by the condensation of [piperidin-4-yl]-diphenyl-methanol with
2-nitro benzene sulfonylchloride in methylene dichloride as solvent and triethyla-
mine as the base. The product obtained was characterized by spectroscopic techni-
ques and the structure was investigated by X-ray crystallography. The compound
crystallizes in the monoclinic crystal class ꢀin the space groupꢀPc with cell para-
ꢀ
meters a ¼ 9.2360(4) A, b ¼ 10.7750(8) A, c ¼ 13.4110(8) A, b ¼ 124.162(4)ꢀ,
ꢀ
V ¼ 1104.35(12)A3 for Z ¼ 2. The structure reveals that the piperidine ring is in
a chair conformation. There is a large discrepancy around the bond angles of
the piperidine N atom. The geometry around the S atom is distorted tetrahedron.
Keywords: conformation; distorted tetrahedron; hydrogen bond; nitrobenzene sulfonyl
piperidine
INTRODUCTION
In the last decade, combinational chemistry has represented the most
promising approach to allow entry to a great number of biological tar-
gets arising from molecular biology and genomic studies [1]. In fact,
the possibility of synthesizing libraries of hundreds of compounds in
a suitable scalable fashion has determined an epochal change in
medicinal chemistry, especially in the fundamental processes of lead
Received October 4, 2007; accepted November 8, 2008.
Address correspondence to Dr. K. S. Rangappa, Department of Studies in Chemistry,
Manasagangotri, University of Mysore, Mysore 570 006, India. E-mail: rangappaks@
gmail.com
145

146
S. B. Benaka Prasad et al.
discovery and optimization [2]. The importance of synthesizing the
organic compounds nitrogen heterocycles, especially of the piperidine
type as subunits of bioactive molecular stimulate the chemist for the
development of new synthetic methods [3]. Piperidine is among the
most important heterocyclic compounds, which exhibits its therapeutic
activity due to its conformationally flexible nature. The accentuated
interest in the piperidine class of opiate analgesics continues to be
expressed in the pharmaceutical community and biological properties
of these agents have been the subject of on-going investigations [4].
Piperidine derivatives possess broad pharmacological action on
central nervous system (CNS), especially on dopaminergic neurotrans-
mission and HIV transcriptase and protease inhibitors [5]. Piperidine
is a key structural component of successful anti-Parkinsons drugs [6]
and displays antipsychotic, antiviral [7], metabolic [8], antimicrobial
[9], antidepresants [10], acetylcholinesterase inhibitors [11], anticon-
vulsants [12], and antimalarial activity [13]. In continuation of our
work on the synthesis of bioactive heterocycles and their biological
evaluation [14], the title compound was synthesized. The compound
obtained was characterized spectroscopically and finally confirmed
by X-ray crystallography.
FIGURE 1 Reaction scheme.

Synthesis and Crystal Structure
147
EXPERIMENTAL
Melting points were determined using SELACO-650 hot stage melting
point apparatus and were uncorrected. The Infrared (IR) spectra were
recorded using a Jasco FTIR-4100 series. Nuclear magnetic resonance
(1H NMR) spectra were recorded on a Shimadzu AMX 400-Bruker,
400 MHz spectrometer using CDCl3 as a solvent and TMS as internal
standard (chemical shift in d ppm). Spin multiplets are given as s
(singlet), d (doublet), t (triplet), dd (doublet of doublet), and m (multi-
plet). Mass and purity were recorded on a LC-MSD-Trap-XCT.
Elemental (CHNS) analyses were obtained on Vario EL III Elementar.
Silica gel column chromatography was performed using Merck 7734
silica gel (60–120 mesh) and Merck made TLC plates. The reaction
scheme is shown in Figure 1.
TABLE 1 Crystal Data and Structure Refinement Table
CCDC Deposition Number
Empirical formula
Formula weight
Temperature
Wavelength
Crystal system
Space group
CCDC 660794
24H24N2O5S
452.51
C
293(2) K
˚
0.71073 A
Monoclinic
Pc
˚
Cell dimensions
a ¼ 9.2360(4) A
˚
b ¼ 10.7750(8) A
˚
c ¼ 13.4110(8) A
b ¼ 124.162(4)ꢀ
3
˚
Volume
Z
Density (calculated)
Absorption coefficient
F000
1104.35(12) A
2
1.361 Mg=m3
0.186 mmꢁ1
476
Crystal size
Theta range for data collection
Index ranges
0.27 ꢂ 0.25 ꢂ 0.2 mm
2.63ꢀ to 25.03ꢀ
ꢁ 10 ꢃ h ꢃ 10
ꢁ 12 ꢃ k ꢃ 11
ꢁ 15 ꢃ l ꢃ 15
Reflections collected
3102
Independent reflections
Absorption correction
Refinement method
Data=restraints=parameters
Goodness-of-fit on F2
Final R indices [I > 2r(I)]
R indices (all data)
3102 [R(int) ¼ 0.0000]
None
Full-matrix least-squares on F2
3102=2=290
1.195
R1 ¼ 0.0367, wR2 ¼ 0.1000
R1 ¼ 0.0379, wR2 ¼ 0.1015
0.105(9)
Extinction coefficient
Largest diff. peak and hole
ꢁ3
˚
0.356 and ꢁ0.254 e ꢄ A

148
S. B. Benaka Prasad et al.
Synthesis of [1-(2-Nitro-benzenesulfonyl)-piperidin-4-yl]-
diphenylmethanol
The compound [1-(2-nitro-benzenesulfonyl)-piperidin-4-yl]-diphenyl-
methanol was obtained by the condensation of [piperidin-4-yl]-diphenyl-
methanol (1.0 g, 3.74 mmol). First [piperidin-4-yl]-diphenyl-methanol
was dissolved in dichloromethane (10 ml) and cooled to 0–5ꢀC in an
ice bath. Then triethylamine (1.136 g, 11.22 mmol) was added to
the cold reaction mixture and stirred for 10 minutes and then
TABLE 2 Atomic Coordinates and Equivalent Thermal Parameters of the
Nonhydrogen Atoms
Atom
x
y
z
Ueq
N1
C2
C3
C4
C5
C6
S7
O8
0.7336(2)
0.5826(3)
0.6487(3)
0.7636(3)
0.9136(3)
0.8447(3)
0.70581(7)
0.8719(3)
0.6152(3)
0.5688(3)
0.6452(3)
0.5474(4)
0.3701(4)
0.2924(4)
0.3913(3)
0.2986(3)
0.2408(4)
0.2788(4)
0.8296(3)
0.9426(2)
0.6735(3)
0.6455(4)
0.5051(5)
0.3929(4)
0.4193(4)
0.5577(4)
0.9379(3)
1.0542(4)
1.1429(5)
1.1200(5)
1.0069(4)
0.9155(4)
0.3808(2)
0.3462(2)
0.2871(2)
0.1742(2)
0.2143(2)
0.2736(3)
0.49136(5)
0.5160(2)
0.5895(2)
0.4350(2)
0.3610(2)
0.3137(3)
0.3381(3)
0.4112(3)
0.4593(3)
0.5421(3)
0.4963(3)
0.6483(2)
0.1114(2)
0.1955(2)
0.0731(2)
0.1234(3)
0.0854(4)
ꢁ0.0033(3)
ꢁ0.0558(3)
ꢁ0.0175(3)
ꢁ0.0055(2)
ꢁ0.0443(3)
ꢁ0.1551(4)
ꢁ0.2290(4)
ꢁ0.1928(3)
ꢁ0.0810(3)
0.2085(2)
0.2125(2)
0.3344(2)
0.3578(2)
0.3464(2)
0.2249(2)
0.11771(6)
0.5160(2)
0.1306(2)
ꢁ0.0324(2)
ꢁ0.0761(2)
ꢁ0.1908(3)
ꢁ0.2648(3)
ꢁ0.2247(3)
ꢁ0.1089(2)
ꢁ0.0751(2)
ꢁ0.0204(3)
ꢁ0.1077(3)
0.4801(2)
0.5766(1)
0.4862(2)
0.5682(3)
0.5719(3)
0.4975(3)
0.4156(3)
0.4106(3)
0.5030(3)
0.6229(3)
0.6479(5)
0.5587(5)
0.4410(5)
0.4125(3)
0.0510(5)
0.0529(5)
0.0514(5)
0.0458(5)
0.0543(5)
0.0551(6)
0.0525(2)
0.0709(6)
0.0681(5)
0.0493(5)
0.0575(6)
0.0676(7)
0.0749(8)
0.0720(8)
0.0547(6)
0.0693(6)
0.0986(9)
0.0957(8)
0.0487(5)
0.0634(5)
0.0467(5)
0.0708(8)
0.0882(1)
0.0684(7)
0.0761(8)
0.0695(7)
0.0569(6)
0.0773(9)
0.0985(1)
0.1010(1)
0.0874(1)
0.0686(7)
O9
C10
C11
C12
C13
C14
C15
N16
O17
O18
C19
O20
C21
C22
C23
C24
C25
C26
C27
C28
C29
C30
C31
C32
P P
Ueq ¼ ð1=3Þ
Uijðaꢅi aꢅj Þðai ꢄ ajÞ.
i
j

Synthesis and Crystal Structure
149
2-Nitrobenzenesulfonyl chloride (0.830 g, 3.74 mmol) was added to the
reaction mixture. The reaction mixture was stirred at room tempera-
ture for 5 hours. The reaction mass was monitored by thin-layer chro-
matography (TLC). After the completion of the reaction, the solvent
was removed under reduced pressure and the residue was taken in
water and extracted with ethyl acetate. The organic layer was washed
with water and dried over anhydrous sodium sulphate. White crystal-
line solid was obtained and was kept in ethyl acetate:methanol (3:1)
for three days. Pure light yellow crystals were obtained after three
days due to the slow evaporation of the solvent. MP: 226ꢀC. Yield:
15.2 g, 90%.
Anal. Calcd. for C24H24N2O5S (in %): C: 63.65, H: 5.32, N: 6.19, S:
7.06. Found C: 63.61, H: 5.29, N: 6.15, S: 7.02.
1H NMR (CDCl3, 400 MHz): d 8.34 (d, 1H, Ar-H), 8.11 (d, 1H, Ar-H),
7.81 (m, 1H, Ar-H), 7.62 (m, 1H, Ar-H), 7.2–7.4 (m,10H, Ar-H), 2.8 (t,
4H, piperidine-CH2ꢁ), 2.15 (s, ꢁOH), 1.5–1.7 (m, 5H, piperidine-CH).
IR (KBr, cm1): ꢁSO2 str 1350 (asymmetric str), ꢁSO2 1279 str
(symmetric str), ꢁOH. FAB Ms m=z (%) 453.14.
CRYSTAL STRUCTURE DETERMINATION
A
single crystal of the title compound with dimensions
0.27 ꢂ 0.25 ꢂ 0.2 mm was chosen for an X-ray diffraction study. The
˚
TABLE 3 Bond Lengths (A)
Atoms
Length
Atoms
Length
N1-C2
N1-C6
N1-S7
C2-C3
C3-C4
C4-C5
C4-C19
C5-C6
S7-O9
1.473(3)
1.478(3)
1.618(2)
1.526(3)
1.526(3)
1.538(3)
1.548(3)
1.518(3)
1.418(2)
1.435(2)
1.778(2)
1.385(3)
1.395(4)
1.372(4)
1.383(5)
1.363(5)
1.385(4)
1.474(4)
N16-O18
N16-O17
C19-O20
C19-C27
C19-C21
C21-C22
C21-C26
C22-C23
C23-C24
C24-C25
C25-C26
C27-C32
C27-C28
C28-C29
C29-C30
C30-C31
C31-C32
1.202(4)
1.227(4)
1.438(3)
1.529(3)
1.545(3)
1.374(4)
1.381(4)
1.387(5)
1.350(5)
1.373(5)
1.381(4)
1.377(5)
1.405(4)
1.379(5)
1.351(7)
1.373(7)
1.396(4)
S7-O8
S7-C10
C10-C15
C10-C11
C11-C12
C12-C13
C13-C14
C14-C15
C15-N16

150
S. B. Benaka Prasad et al.
data were collected on a DIPLabo Image Plate system equipped with a
normal focus, 3 kW sealed X-ray source (graphite monochromated
MoKa).
The crystal-to-detector distance is fixed at 120 mm with a detector
area of 441 ꢂ 240 mm2. Thirty-six frames of data were collected at
room temperature by the oscillation method. Each exposure of the
image plate was set to a period of 400 s. Successive frames were
scanned in steps of 5ꢀ per minute with an oscillation range of 5ꢀ. Image
processing and data reduction were done using Denzo [15]. The reflec-
tions were merged with Scalepack [16]. All of the frames could be
indexed using a primitive monoclinic lattice. Absorption correction
was not applied. The structure was solved by direct methods using
SHELXS-97 [17]. Least-squares refinement using SHELXL-97 [18]
with isotropic temperature factors for all the nonhydrogen atoms
converged the residual R1 to 0.1216. Subsequent refinements were
TABLE 4 Bond Angles (ꢀ)
Atoms
Angle
Atoms
Angle
C2-N1-C6
C2-N1-S7
C6-N1-S7
N1-C2-C3
C4-C3-C2
C3-C4-C5
C3-C4-C19
C5-C4-C19
C6-C5-C4
N1-C6-C5
O9-S7-O8
O9-S7-N1
O8-S7-N1
O9-S7-C10
O8-S7-C10
N1-S7-C10
C15-C10-C11
C15-C10-S7
C11-C10-S7
C12-C11-C10
C11-C12-C13
C14-C13-C12
C13-C14-C15
C10-C15-C14
C10-C15-N16
C14-C15-N16
112.9(2)
117.4(1)
119.4(2)
109.1(2)
111.5(2)
108.4(2)
112.4(2)
112.8(2)
111.5(2)
109.0(2)
119.2(1)
108.2(1)
107.7(1)
107.4(1)
105.7(1)
108.2(1)
117.6(2)
124.7(2)
117.7(2)
121.0(2)
120.2(3)
120.1(3)
119.7(3)
121.4(3)
122.4(2)
116.1(2)
O18-N16-O17
O18-N16-C15
O17-N16-C15
O20-C19-C27
O20-C19-C21
C27-C19-C21
O20-C19-C4
C27-C19-C4
C21-C19-C4
C22-C21-C26
C22-C21-C19
C26-C21-C19
C21-C22-C23
C24-C23-C22
C23-C24-C25
C24-C25-C26
C21-C26-C25
C32-C27-C28
C32-C27-C19
C28-C27-C19
C29-C28-C27
C30-C29-C28
C29-C30-C31
C30-C31-C32
C27-C32-C31
124.9(3)
117.4(3)
117.6(3)
106.0(2)
110.4(2)
107.1(2)
109.5(2)
113.4(2)
110.4(2)
116.7(3)
122.5(2)
120.7(2)
120.8(3)
121.8(3)
118.4(3)
120.0(3)
122.1(3)
118.3(3)
123.5(2)
117.9(3)
120.2(4)
121.3(4)
119.4(3)
120.8(4)
120.0(3)

Synthesis and Crystal Structure
151
FIGURE 2 ORTEP of the molecule with thermal ellipsoids drawn at 50%
probability.
carried out with anisotropic thermal parameters for nonhydrogen
atoms and isotropic temperature factors for the hydrogen atoms which
were placed at chemically acceptable positions. The hydrogen atoms
were allowed to ride on their parent atoms. After eight cycles of refine-
ment, the residual converged to 0.0367. The details of crystal data and
refinement are given in Table l.1 Table 2 gives the atomic coordinates
and equivalent thermal parameters of the nonhydrogen atoms. Table 3
and Table 4 give the list of bond lengths and bond angles, respectively,
which are in good agreement with the standard values. The ORTEP of
the molecule with thermal ellipsoids drawn at 50% probability is
shown in Figure 2.
A study of the torsion angles, asymmetric parameters, and least-
squares plane calculations reveals that the piperidine ring in the
structure is in a chair conformation with the atoms N1 and C4
˚
˚
deviating ꢁ0.243(2) A and 0.236(3) A from the Cremer and Pople
plane [19] defined by the atoms C2=C3=C5=C6. This is confirmed by
ꢀ
˚
the puckering parameters Q ¼ 0.5861(28) A, h ¼ 180.00(26) , and
u ¼ 175(27)ꢀ. The bonds N1ꢁS7 and C4ꢁC19 make an angle of
84.15(11)ꢀ and 72.96(14)ꢀ with the Cremer and Pople plane of the
1‘‘CCDC 660794 contains the supplementary crystallographic data for this article.
These data can be obtained free of charge via www.ccdc.cam.ac.uk/conts/retrieving.html
or from The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2
1EZ, UK; fax: þ44(0)1223-336033. E-mail: deposit@ccdc.cam.ac.uk’’

152
S. B. Benaka Prasad et al.
FIGURE 3 Packing of the molecules when viewed down the a axis.
piperidine ring and thus lie in the equatorial plane of the piperidine
ring. The dihedral angle between the least-squares plane of the piperi-
dine ring and the phenyl ring C21ꢁC26 is 87.40(14)ꢀ implying that the
phenyl ring is nearly perpendicular to the plane of the piperidine ring.
The other phenyl ring C27ꢁC32 makes a dihedral angle of 59.62(18)ꢀ
with the least-squares plane of the piperidine ring. The dihedral angle
between the two phenyl rings bridged by the alcoholic group is
84.74(19)ꢀ. The nitrophenyl ring is inclined at an angle of 66.91(13)ꢀ
to the sulfonyl plane. The nitro group is twisted out of the plane of
the adjacent aryl ring as indicated by the torsion angle values of
ꢁ81.0(4)ꢀ and ꢁ87.2(4)ꢀ for O18-N16-C15-C14 and O17-N16-
C15-C10, respectively. The sulfonyl atoms O8 and O9 are oriented in
ꢁsynclinal and þsynclinal conformations as indicated by the torsion
angle values of ꢁ42.0(2)ꢀ and 45.1(2)ꢀ for C6-N1-S7-O8 and
C2-N1-S7-O9, respectively.
The geometry around the S atom is distorted tetrahedron, with the
largest deviations observed for the O-S-O [O8-S7-O9 ¼ 119.2(l)ꢀ] and

Synthesis and Crystal Structure
153
O-S-N angles [O9 S7N1 ¼ 1O8.2(1)ꢀ. This widening of angles is due to
=
the repulsive interaction between the two short S O bonds. The S-N
˚
bond distance lies within the expected range of 1.60–1.69 A. The
reduction of the N1-S7-C10 angle to 108.2(1)ꢀ from the ideal tetra-
hedral value is attributed to the Thorpe-Ingold effect [20]. The struc-
ture exhibits an intermolecular hydrogen bond of the type C-H ꢄꢄꢄ O.
The intermolecular hydrogen bond C14-H14 . . . O8 between the nitro-
phenyl ring and the sulfonyl group has a length of 3.323(5)ꢀ and an
angle of 167ꢀ with a symmetry code ꢁ1 þ x, 1 ꢁy, ꢁ1 þ z. The packing
of the molecules when viewed down the a axis indicates that the
molecules are stacked in pairs and they form hydrogen bonded dimers
(Fig. 3).
ACKNOWLEDGMENTS
The authors are grateful to DST and CSIR, New Delhi for financial
support under the projects SP=I2=FOO=93 and No. 01(1904)=03=
EMR-II 2004. Also, the CHNS, IR data obtained from the instrument
granted by DST-FIST and UGC-SAP (phase I) are greatly acknowledged.
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