A piperidinium-carbodithioate salt: Synthesis, crystal structure, spectral, cation-interaction and electrochemical studies

Article abstract of DOI:10.1016/j.molstruc.2019.04.024

An ionic compound 4-methyl-piperidinium 4-methyl-piperidinecarbodithioate (MPMP) C₆H₁₄N⁺·C₇H₁₂NS₂ ^ˉ has been synthesized from the one pot reaction of 4-methylpiperidine and carbon disulfide. The compound is well characterized on the basis of elemental analysis, IR, NMR, UV–visible and single crystal X-ray diffraction data. The compound introduces the concept of hydrogen bonding interactions in two ionic species and its effect on crystal packing. The asymmetric unit of the compound consists of 4-methyl-piperidinium cation and 4-methyl-piperidinecarbodithioate anion. Inter and intramolecular N[sbnd]H?S contacts link piperidinium cation and carbodithioate anion and stabilize the crystal packing in solid state. The compound crystallizes in monoclinic system with space group P 2₁/c. The interaction of the compound with different metal ion solutions is studied and it shows interesting red shifts with Co²⁺, Cu⁺, Cu²⁺ and Ni²⁺ ions which suggests that MPMP may be a useful probe for sensing of these ions. Cyclic voltammetric analysis of the compound exhibits quasi-reversible redox behaviour.

Full text of DOI:10.1016/j.molstruc.2019.04.024

Accepted Manuscript
A piperidinium-carbodithioate salt: Synthesis, crystal structure, spectral, cation-
interaction and electrochemical studies
Paras Nath, M.K. Bharty, L.B. Prasad, R.J. Butcher, J.P. Jesinski
PII:
S0022-2860(19)30419-3
DOI:
https://doi.org/10.1016/j.molstruc.2019.04.024
MOLSTR 26396
Reference:
To appear in: Journal of Molecular Structure
Received Date: 27 September 2018
Revised Date: 4 April 2019
Accepted Date: 4 April 2019
Please cite this article as: P. Nath, M.K. Bharty, L.B. Prasad, R.J. Butcher, J.P. Jesinski, A piperidinium-
carbodithioate salt: Synthesis, crystal structure, spectral, cation-interaction and electrochemical studies,
Journal of Molecular Structure (2019), doi: https://doi.org/10.1016/j.molstruc.2019.04.024.
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to
our customers we are providing this early version of the manuscript. The manuscript will undergo
copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please
note that during the production process errors may be discovered which could affect the content, and all
legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT
Graphical Abstract (Picture)

ACCEPTED MANUSCRIPT
Re-revised Manuscript
A piperidinium-carbodithioate salt: Synthesis, crystal structure,
spectral, cation-interaction and electrochemical studies
a,
a,
a
b
c
Paras Nath , M. K. Bharty *, L.B. Prasad , R. J. Butcher , J. P. Jesinski
a
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221 005, India
b
Department of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA
Department of Chemistry, Keene State College, 229 Main Street, Keene, NH, 03435-2001, USA
c
*
Corresponding author. Tel.: +91-5426702447, Fax: 0542-2368127, E-mail: mkbharty@bhu.ac.in
ABSTRACT
An ionic compound 4-methyl-piperidinium 4-methyl-piperidinecarbodithioate
+
¯
(
MPMP) C H N ·C H NS has been synthesized from the one pot reaction of 4-
6 14 7 12 2
methylpiperidine and carbon disulfide. The compound is well characterized on the basis of
elemental analysis, IR, NMR, UV-visible and single crystal X-ray diffraction data. The
compound introduces the concept of hydrogen bonding interactions in two ionic species and
its effect on crystal packing. The asymmetric unit of the compound consists of 4-methyl-
piperidinium cation and 4-methyl-piperidinecarbodithioate anion. Inter and intramolecular
N–H···S contacts link piperidinium cation and carbodithioate anion and stabilize the crystal
packing in solid state. The compound crystallizes in monoclinic system with space group P
21
/c. The interaction of the compound with different metal ion solutions is studied and it
2+
+
2+
2+
shows interesting red shifts with Co , Cu , Cu and Ni ions which suggests that MPMP
may be a useful probe for sensing of these ions. Cyclic voltammetric analysis of the
compound exhibits quasi-reversible redox behaviour.
Keywords: piperidinium; carbodithioate; salt; ionic compound; cation interaction;
1.
Introduction
Dithiocarbamate represents an interesting class of dithio compounds with a strong chelating
ability towards various transition metal ions and forms interesting coloured complexes. The
dithiocarbamate derivatives have been widely used in analytical chemistry as complexing
1

ACCEPTED MANUSCRIPT
agents [1]. The qualitative analysis of metal complexes can be spectrophotometrically
performed on the basis of their UV-Vis absorptions [2]. Dithiocarbamates have been used as
pesticide since long ago but attracted the interests of medicinal chemists due to their metal
binding capacity and exhibit a broad-spectrum of biological activities such as antimicrobial,
anticancer, etc. [3]. They are also applicable as anti-tubercular [4] anti-alcoholic drug [5]
and agent for the treatment of Alzheimer's disease [6]. Piperidine is an important
pharmacophore and an excellent heterocyclic scaffold in the field of drug discovery which
provides numerous opportunities exploring this moiety as an anticancer and antimicrobial
agent by acting on various receptors [7,8]. Dithiocarbamates can serve as antioxidants for
increasing the durability and photo-stability of a variety of polymers, oils and other
materials [9]. The piperidine dithiocarbamato ligands generally form four membered S,S-
chelate ring and bridge two metal centres due to the dominant contribution of the resonance
form III (Scheme 1) [10-13].
The study of the 4-methyl-piperidinium 4-methyl-piperidine-carbodithioate is
interesting because it introduces the concept of hydrogen bonding in two ionic species and
its effect on crystal packing. A few ionic compounds of piperidine with CO , NO and SO
2
2
2
are reported but no single crystal X-ray analysis is yet available on compound having
piperidinium-carbodithioate cation-anion pair [14-16]. In view of the above importance, we
report herein the synthesis, spectral and structural characterization of an ionic compound
containing a piperidinium cation and a piperidine-dithiocarbamate anion.
S
S
S
S
S
S
N
N
N
H C
I
H C
II
H C
III
3
3
3
Scheme 1. Resonance structures of 4-methyl-piperidine-carbodithioate
2

ACCEPTED MANUSCRIPT
2.
Experimental
2.1. Chemicals and starting materials
Commercial reagents were used without further purification. 4-Methyl-piperidine was
purchased from Sigma Aldrich. Other chemicals were of reagent grade and used as
purchased without further purification. All the synthetic manipulations were carried out in
open atmosphere and at room temperature. The solvents were dried and distilled before use
following the standard procedure.
2.2. Physical measurements
The carbon, hydrogen, nitrogen and sulfur contents were determined on a CHN Model CE-
40 Analyzer and on an Elementar Vario EL III Carlo Erba 1108. Infrared spectra were
4
-1
recorded in the 4000–400 cm region as KBr pellets on a Varian Excalibur 3100 FT-IR
1
13
spectrophotometer. H and C NMR spectra were recorded in CDCl on a JEOL JNM-
3
ECZ500R/S1 FT NMR spectrometer using TMS as an internal reference. The UV-vis
-5
absorption spectra were recorded at 2x10 M solution in MeOH on a SIMADZU 1700 UV–
Vis spectrophotometer and emission spectrum was recorded on Agilent Technologies Cary
Eclipse Fluorescence Spectrophotometer. Electrochemical studies were performed on a
Metrohm (Netherlands) Instrument (Autolab PGSTAT204) attached with NOVA 1.11
software at room temperature under N atmosphere. A three electrode, one compartment cell
2
with solid Pt electrode as working electrode, platinum wire as counter electrode and
Ag/AgCl as reference electrode was used.
2.3. X-ray crystallography
+
-
Single crystal X-ray diffraction data collection for C H N ·C H NS were
6
14
7
12
2
performed on an Xcalibur, Eos, Gemini diffractometer equipped with CrysAlis Pro., using a
3

ACCEPTED MANUSCRIPT
Copper monochromated Cu Kα (λ = 1.54178 Å) radiation source at 173(2) K was used.
Multi-scan absorption correction was applied to the X-ray data of both compounds. The
structure was solved by direct methods (SHELXL-2013) and refined by full matrix least-
2
square on F (SHELXL) using anisotropic displacement parameters for all non-hydrogen
atoms. All hydrogen atoms were included in calculated position and refined with a riding
model [17-19]. Figures were drawn using the programs MERCURY and ORTEP-3 [20,21].
2.4. Synthesis of 4-methyl-piperidinium 4-methyl-piperidine-carbodithioate (MPMP)
4-Methyl-piperidinium 4-methyl-piperidine-carbodithioate was prepared by the drop-wise
addition of carbon disulfide (0.7 mL, 10 mmol) into a cold ethanolic solution of 4-
methylpiperidine (2.4 mL, 20 mmol). The mixture stirred for 1 h in an ice bath. The white
solid obtained was filtered off, washed with ethanol and dried under reduced pressure. The
compound was dissolved in methanol and kept for crystallization. Colourless crystals
suitable for X-ray analysis were obtained after the slow evaporation of the solvent over a
period of 15 days (Scheme 2). MPMP is easily soluble in common solvents including water.
Yield: 80%; Mp. 188-190 °C. Anal. Calc. for C H N S 274.48 (%): C, 56.88; H, 9.54; N,
13
26
2 2
-
1
1
2
1
2
0.20; S, 23.36. Found: C, 56.55; H, 9.40; N, 10.56; S, 23.42. IR (KBr, cm ): 3187 ν(N–H),
1
952-2906 ν(C–H), 1586 ν(C–N), 1015 ν(C=S). H NMR (δ, ppm): 0.92 (two d, 6H, CH ,),
3
.12–1.22 (m, 2H, H-3, H-6), 1.54–1.72 (m, 8H, H-2, H-5), 2.79 (t, 2H, H-1axial, J = 12 Hz),
.99 (t, 2H, H-4axial J = 12 Hz), 3.72 (d, 2H, H-1equatorial, J = 12.5 Hz), 5.62 (d, 2H, H-
1
3
4equatorial, J = 12.5 Hz), 7.45 (2H, NH) (Scheme 2). C NMR (δ, ppm): 21.4 (CH ), 29.0
3
(C2), 30.8 (C3, C5), 34.2 (C6), 44.5 (C1), 51.1 (C4), 208.6 (C=S) (Scheme 2).
4

ACCEPTED MANUSCRIPT
-
S
S
+
H
N
H
N
2
1
1
2
EtOH
N
2
+ CS2
4
5
4
5
Ice bath, 1 h
2
3
6
CH3
CH3
CH3
+
¯
Scheme 2. Synthesis of C H N ·C H NS (MPMP)
6
14
7
12
2
3.
Result and discussion
3.1.
IR spectrum
+
¯
2
The IR spectrum of C H N ·C H NS showed absorptions due to the stretching modes of
6
14
7
12
N-H ν(3187), C-N ν(1586) and C=S ν(1015), respectively. The absorption bands around
-1
2
925 cm are attributed to aliphatic C–H stretches (Supplementary Fig. 1). Compound
shows a slight lower stretching vibration in ν N-H (3187) as compared to other compound,
indicating that the dithio sulfur is involved in hydrogen bonding [16]. The compound
-1
-1
exhibits a band at 1586 cm with a positive shift of 115 cm for C-N stretching, when
compared to 4-methyl piperidine which confirms the conjugation of CS with piperidine
2
-1
nitrogen [12]. Compound showed two absorptions bands at 1462 and 1379 cm due to
asymmetric symmetric bending vibrations of CH group.
3
3.2. NMR spectra
1
+
¯
The H NMR spectrum of C H N ·C H NS showed double doublet signals at δ
6
14
7
12
2
0.92 ppm due to methyl protons. The multiplet signals were observed in the range of δ 1.12–
1.22 and 1.54–1.72 ppm due to H-3, H-6 and H-2, H-5 protons, respectively (Scheme 2). In
the carbdithioate anion the axial and equatorial H-4 protons appeared at 2.99 (t) and 5.62 (d)
ppm, respectively while the axial and equatorial protons (H-1) in the piperidinium cation
appeared at 2.79 (t) and 3.72 (d) ppm. For the axial protons both the geminal coupling with
5

ACCEPTED MANUSCRIPT
the equatorial protons as well as the vicinal coupling with the adjacent axial protons were
large but in case of equatorial protons, only the geminal coupling with the axial protons was
large. The deshielding of equatorial and axial protons was due to high electron density at
nitrogen atom [22, 23]. However, the equatorial protons were more deshielded than the axial
protons (Supplementary Fig. 2) [24]. A small broad signal at δ 7.45 ppm for N-H protons is
observed which is highly deshielded when compared to N-H protons of 4-methyl piperidine
(δ 2.32 ppm). This suggests strong interaction between N-H protons and dithio sulfur atoms.
1
3
+
¯
The C NMR spectrum of C H N ·C H NS showed a signal at δ 208.6 ppm due
6
14
7
12
2
to the CS carbon attributed to the considerable double bond character in the C-N bond of
2
the dithiocarbamato group which supports the formation of the compound (MPMP). In the
piperidine ring, carbon atoms adjacent to the nitrogen were more deshielded than other
carbon atoms. The signals for C1, C2 and C3 in cation were observed at δ 44.5, 29.0 and
3
0.8 ppm, respectively (Scheme 2). Whereas the signals for C4, C5, C6 in anion appeared at
δ 51.1, 30.8 and 34.2 ppm, respectively. The methyl carbons appear δ 21.4 at ppm
Supplementary Fig. 3) [11, 12].
(
3.3. Electronic absorption and emission spectra
-1
The compound MPMP displays two high energy bands at at 34800 and 39000 cm which
may be assigned to n→π* and π→π* transitions which are attributed to the NCS2
-1
chromophore (Fig. 1). Upon excitation at 34800 cm , the compound MPMP exhibited
-1
maximum emission at 30500 cm (Fig. 3).
3.4. Cation Interaction Behaviour
-5
UV-Vis absorption spectra were recorded at 2 x 10 M in methanol. The absorption spectral
-1
bands observed for MPMP at 34850 and 39050 cm may be assigned to n → π* and π → π*
transitions due to NCS moiety (Fig. 1). The potassium derivative of the same anion
6

ACCEPTED MANUSCRIPT
(potassium 4-methylpiperidine-carbodithioate) showed absorption maxima at 33650 and
-1
-1
3
7700 cm . Thus MPMP shows blue shift of 1800 and 1650 cm , respectively regarding its
potassium derivative. We detected the colour change and new d-d absorption bands upon
addition of different metal(II) acetates due to coordination between metal ion and sulfur
donor atom (Fig. 1.a). Upon addition of cobalt acetate solution the colour changed to green
-1
and a new band was observed at 30800 cm whereas upon addition of copper(II) acetate
-1
solution showed brown colour and absorption band at 23000 cm . These values are close to
the absorption maxima reported in their metal complexes with 4-methylpiperidine-
-1
carbodithioate [12]. The band around 23000 cm for Cu-MPMP may be assigned to the
2
2
2
2
envelope of the B → A , B and E transitions and suggests a square planar geometry
1
g
1g
2g
g
for the complex [12,25]. Upon adition of manganese(II) acetate in MPMP solution colour
-1
changed to brown and a band was observed at 21900 cm which is the characteristic of six
5
5
coordinate Mn(III) and may be assigned to the E → T transition [24,26]. Ni-MPMP
g
2g
-1
solution gives spectral bands at 25550 and 18350 cm and it is the characteristic of square-
planar Ni(II) complex [24,27]. The diamagnetic Zn(II) complex did not show d-d transition.
The interaction behaviour was also studied with cuprous chloride, ferrous chloride, ferric
sulphate, chromium acetate and mercuric chloride besides above metal(II) acetates (Fig.
1.b). Upon addition of Cu(I) chloride in MPMP, colour changed into greenish-brown and a
-1
new broad band at 26000 cm was observed. Ferrous chloride and ferric sulphate gave dark
red and brown colour, respectively in MPMP solution, while Cr(III) acetate and Hg(II)
chloride ions did not showed any significant colour change (Fig. 2). This study suggests that
2
+
+
2+
2+
Co , Cu , Cu and Ni ions showed significant red shift in UV-visible spectra, hence
MPMP may be a good probe for sensing these ions in solution [2].
-1
The high energy absorption maxima in the range of 39000-30800 cm can be
attributed to the NCS chromophore. It is noteworthy that free MPMP showed two bands at
2
7

ACCEPTED MANUSCRIPT
-1
3
4850 and 39050 cm due to NCS moiety while upon addition of metal ions the former
2
band either disappeared or its intensity decreased. It also suggests the interaction of metal
ions with NCS moiety. Some possible modes of cation interactions are depicted in scheme
2
2
+
3+
3
. M and M are at the border line of hard and soft lewis acid, therefore they may exist
with slight different in their stability (Scheme 3, III).
S
S
S
S
M
N
N
N
M
M
S
S
H C
H C
H C
3
3
3
I
II
III
Scheme 3. Possible modes of interactions of MPMP with various cations
+
¯
3
.5. Crystal structure description of C H N ·C H NS
6
14
7
12
2
+
¯
2
The molecular structure of C H N ·C H NS with atom numbering scheme is
6
14
7
12
shown in Fig. 4. The details of data collection, structure solution and refinement are listed in
Table 1. Selected bond lengths and angles are given in Tables 2 and hydrogen bonding
parameters are given in Table 3.
+
¯
2
The molecule C H N ·C H NS consists of 4-methyl-piperidinium and 4-methyl-
6
14
7
12
piperidinecarbodithioate cation-anion pair. In the piperidinium cation, the C–C and C–N
single bonds are similar to those reported in other piperidinium cation [14,15] while in anion
the C–N bond lengths [C8–N2 = 1.487(3), C12–N2 = 1.485(3) Å] are shorter than C–N
single bond suggesting partial double bond character [12,28]. The C–S bond lengths [C1–S1
=
1.717(2) and C1–S2 = 1.721(2) Å] have well agreement with other reported
piperidinecarbodithioate anion [12,29]. These C–S bond distances are intermediate between
C–S single and C=S double bond distances which attribute to the delocalization of the π-
electrons in the NCS moiety [12,30].
2
In the crystal structure, N2–H2D···S1 [2.53 Å] and N2–H2D···S2 [2.65 Å] contacts
link the dithiocarbamate anion to the piperidinium cation in the asymmetric unit (Fig. 4). In
8

ACCEPTED MANUSCRIPT
addition, intermolecular N–H···S [N2-H2C···S1#1 = 2.54 Å; N2-H2C···S2#1 = 2.75 Å]
2
contacts generating R1 (4) ring motifs are also observed (Fig. 5). These hydrogen bonding
cantacts are working between cationic and anionic species and stabilize the crystal structure
of compound in solid state. The hydrogen bonds between S···H successfully disperse the
energy-rich electronic density at the sulfur atoms of the dithiocarbamate ion in combination
+
with the electronic attraction between N ···S; thus the dithiocarbamate ion in the complex
acquires a stable state. The crystal structure of the compound is also stabilized by
intramolecular C–H···S contacts (Table 3).
3.6
Electrochemical characterization
+
¯
The electrochemical behaviour of the compound MPMP {C H N ·C H NS } was studied
6
14
7
12
2
using cyclic voltammetry and is depicted as Fig. 6 and 7. The cyclic voltammograms were
-3
recorded in 10 M MPMP solution in CH CN at a platinum electrode using 0.1M TBAP as
3
supporting electrolyte. MPMP exhibited two sets of cathodic-anodic peaks at 0.530 V, 0.460
-1
V and -0.100 V, -0.250 V, respectively at 0.020 V.s scan rate and the separation between
the cathodic and anodic peak potentials (ꢀE = E - E ) of 0.070 V and 0.150 V indicate
p
pa
pc
quasi-reversible redox behaviours. The peack separation potential of 0.070 V for cathodic
and anodic peak at 0.536 V, 0.460 V is slightly high as compared to that expected for one-
electron process and hence it can be assumed that the redox process is coupled with some
chemical reaction accompanied with the charge transfer from piperidinium to carbodithioate
moiety with a formal redox potential E = (E + E )/2 = 0.495 V (Fig. 7). On scaning at
pa
pc
higher scan rates the cathodic peak potential slightly shifted and separation between
cathodic and anodic peaks increased which indicated that the redox process is not
completely reversible. At scan rates 0.020, 0.050, 0.100, 0.150 and 0.200 V, the peak
separation was 0.070, 0.076, 0.080, 0.092 and 0.100 V, respectively (Fig. 6) [12,31].
9

ACCEPTED MANUSCRIPT
4.
Conclusions
+
¯
In this paper we reports the synthesis and structure of an organic salt C H N ·C H NS .
6
14
7
12
2
The compound was synthesized using 4-methylpiperidine and carbon sulfide in one step.
The compound is characterised by various physicochemical methods. The molecule
crystallizes in monoclinic system with space group P 2 /c. The asymmetric unit of molecule
1
+
¯
C H N ·C H NS
2
consists
of
4-methyl-piperidinium
and
4-methyl-
6
14
7
12
piperidinecarbodithioate cation-anion pair which are linked via inter and intramolecular
piperidinium N-H···S carbodithioate interactions. In the UV-Vis absorption spectrum of the
-1
compound bands observed at 34800 and 39000 cm may be assigned to n → π* and π → π*
-1
transitions in NCS moiety. While upon excitation at 34800 cm it exhibited maximum
-1
emission at 30500 cm . The behaviour of the compound in different metal ion solutions is
2
+
+
2+
2+
studied and it shows interesting red shifts with Co , Cu , Cu and Ni ion which suggests
+
¯
that the compound C H N ·C H NS may be useful in sensing of these ions in solution.
6
14
7
12
2
-1
Cyclic voltammetric analysis of the compond at 20 mV.s showed peak separation potential
of 0.070 V between cathodic and anodic peak with a formal redox potential E = (E + E )/2
pa
pc
=
0.495 V which is slightly high as compared to that expected for one-electron process and
hence the compound exhibits a quasi-reversible redox behaviour.
5.
Supplementary material
+
¯
CCDC 1543175 contains the supplementary crystallographic data for C H N ·C H NS
2
6
14
7
12
which can be obtained free of charge from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
Supplementary data associated with this article can be found, in the online version,
at https://doi.org/.................
Acknowledgements
1
0

ACCEPTED MANUSCRIPT
Dr M. K. Bharty thanks the Science and Engineering Research Board, India for the award of
a Project (No. SB/EMEQ-150/2014). Prof. J. P. Jesinski acknowledges the NSF-MRI
program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer.
References
[
[
[
[
[
1] G. Hogarth, Prog. Inorg. Chem. 53 (2005) 71-561.
2] Z. Valicsek, Ottó Horváth, Microchem. J. 107 (2013) 47-62.
3] V. Bala, G. Gupta, V.L. Sharma, Mini Rev. Med. Chem. 14 (2014) 1021-1032.
4] E.N. Petersen, Acta Psychiat. Scand. 8 (1962) 7.
5] G.D. Thorn, R.A. Ludwig, The Dithiocarbamates and Related Compounds, Elsevier,
Amsterdam 1962.
[
[
[
6] N. Jiang, Q. Huang, J. Liu, N. Liang, Q. Li, Q. Li, S. Xie, Eur. J. Med. Chem. 146
(
2018) 287-298.
7] P. Parthiban, S. Balasubramanian, G. Aridoss, S. Kabilan, Med. Chem. Res. 14
2005) 523-538.
8] P. Goel, O. Alam, M.J. Naim, F. Nawaz, M. Iqbal, M.I. Alam, Eur. J. Med. Chem.
57 ( 2018) 480-502.
(
1
[
[
9] R. Becker, A. Knorr, Lubr. Sci. 8 (1996) 95-117.
10] A.N. Gupta, V. Kumar, V. Singh, A. Rajput, L.B. Prasad, M.G.B. Drew, N. Singh, J.
Organomet. Chem. 787 (2015) 65.
[
[
11] P. Nath, M.K. Bharty, S.K. Kushawaha, B. Maiti, Polyhedron, 151 (2018) 503.
12] P. Nath, M.K. Bharty, B. Maiti, A. Bharti, R.J. Butcher, J.L. Wikaira, N.K. Singh,
RSC Adv. 6 (2016) 93867.
[
13] N. Srinivasan, S. Thirumaran, S. Ciattini, J. Mol. Struct. 936 (2009) 234.
1
1

ACCEPTED MANUSCRIPT
[
[
[
14] H. Jiang, S. Zhang, Y. Xu, African Journal of Pure and Applied Chemistry, 3 (2009)
126-130.
15] N.S. Sowmya, S. Sampathkrishnan, S. Sudhahar, G. Chakkaravarthi, R.M. Kumar,
Acta Crystallogr. Section E, 70 (2014) 559-561.
16] N. Maier, J. Schiewe, H. Matschiner, C. Maschmeier, R. Boese, Phosphorus Sulfur
Silicon Relat. Elem. 91 (1994) 179-188. DOI: 10.1080/10426509408021944
17] G.M. Sheldrick Acta Crystallogr. Section A, 71 (2015) 3-8.
[
[
[
[
18] G.M. Sheldrick Acta Crystallogr. Section C, 71 (2015) 3-8.
19] G.M. Sheldrick, Acta Crystallogr. Section A, 64 (2008) 112.
20] C.F. Macrae, I.J. Bruno, J.A. Chisholm, P.R. Edgington, P. McCabe, E. Pidcock, L.
Rodriguez-Monge, R. Taylor, J. van de Streek, P.A. Wood, J. Appl. Cryst. 41 (2008)
466.
[
[
21] L.J. Farrugia, J. Appl. Cryst. 49 (2012) 849.
22] B.A. Prakasam, K. Ramalingam, G. Bocelli, A. Cantoni, Polyhedron 26 (2007)
4
489-4493.
23] N. Srinivasan, S. Thirumaran, S. Kohli, Rajnikant, J. Chem. Crystallogr. 40 (2010)
05-509.
24] N. Srinivasan, P.J. Rani, S. Thirumaran, J. Coord. Chem. 62 (2009) 1271-1277.
[
5
[
[
nd
25] A.B.P. Lever, Inorganic Electronic Spectroscopy, Elsevier, Amsterdam, 2 edn
1984)
26] A.C. Fabretti, G.C. Franchini, C. Preti, G. Toshi, P. Zannini, Transition Met. Chem.
0 (1985) 284-287.
(
[
[
1
27] B.S. Manhas, M.P. Kaur, K. Kaur, B.C. Verma, S.B. Kalia, Synth. React. Inorg.
Met. –Org. Chem. 29 (1999) 1009-1021.
1
2

ACCEPTED MANUSCRIPT
[
28] N.K. Singh, A.K. Pandey, M. Singh, M.K. Bharty, R.J. Butcher, Acta Crystallogr.
Section E, 63 (2007) o4327-o4327.
[
[
29] A.C. Mafud, MT.P. Gambardella, Acta Crystallogr. Section E, 67 (2011) o879-o879.
30] U.K. Chaudhari, A. Bharti, P. Nath, U.P. Azad, R. Prakash, R. J. Butcher, M.K.
Bharty, J. Mol. Struct. 1177 (2019) 260-268.
[
31] R.K. Dani, M.K. Bharty, O. Prakash, R.K. Singh, B. Prashanth, S. Singh, N.K. Singh
J. Coord. Chem. 68 (2015) 2666-2681.
1
3

ACC
+
EPTED MANUSCRIPT
Table 1. Crystallographic data for C H N ·C H NS
2
¯
6
14
7
12
Empirical formula
Formula weight
Crystal system
Space group
T ( K)
C H N S
13 26 2 2
274.48
Monoclinic
P 2 /c
1
173(2)
λ, Cu Kα (Å)
a (Å)
1.54178
11.2982(7)
15.5679(6)
9.5884(5)
90
b (Å)
c (Å)
α, γ(º)
β (º)
110.593(6)
7
7.597(7)
3
V, (Å )
1578.73(15)
Z
4
3
ρ calcd (g/cm )
1.155
2.91
600
-
1
ꢀ
(mm )
F(000)
3
Crystal size(mm )
0.30×0.20×0.15
4.180-71.306
θ range for data collections(º)
Index ranges
-13≤h≤13, -18≤k≤11, -11≤l≤10
5641
No. of reflections collected
No. of independent reflections(Rint)
No. of data/restrains/parameters
2996 (Rint = 0.044)
2996 / 0 / 156
1.102
2
Goodness-of-fit on F
a
b
R , wR [(I>2σ(I)]
0.0518, 0.1364
0.0604, 0.1445
1
2
a
b
R , wR (all data)
1
2
-
3
Largest difference in peak /hole (e.Å ) 0.44, −0.33
CCDC 1543175
a
b
2
2
2
2 2 1/2
o
R = Σ||F | – |Fc||Σ|F |; R = [Σw (|F | – |F |) /Σw|F | ]
1
o
o
2
o
c
+
¯
Table 2 Selected bond lengths and angles for C H N ·C H NS
2
6
14
7
12
Bond lengths (Å)
S1-C1
Bond angles (°)
C1-N1-C6
C1-N1-C2
C6-N1-C2
C12-N2-C8
N1-C1-S1
1.717(2)
1.721(2)
1.349(3)
1.463(3)
1.465(3)
1.485(3)
1.487(3)
1.509(3)
1.521(3)
1.520(3)
1.526(4)
1.527(4)
1.516(3)
123.30(19)
123.69(19)
112.78(18)
112.11(17)
120.29(16)
120.21(16)
119.49(12)
111.9(2)
S2-C1
N1-C1
N1-C6
N1-C2
N2-C12
N2-C8
N1-C1-S2
S1-C1-S2
C2-C3
C3-C4-C7
C10-C13
C3-C4
C3-C4-C5
109.00(19)
110.8(2)
C7-C4-C5
C4-C7
C13-C10-C11
C13-C10-C9
C11-C10-C9
111.3(2)
C4-C5
111.5(2)
C5-C6
108.80(17)

ACCEPTED MANUSCRIPT
+
¯
Table 3. Inter and intramolecular hydrogen bonds [Å and º] for C H N ·C H NS
6
14
7
12
2
D-H···A
d(D-H)
0.91
0.91
0.91
0.91
0.99
0.99
d(H···A)
2.54
d(D···A)
<(DHA)
149.9
140.7
148.8
140.5
114.5
114.6
N2-H2C···S1#1
N2-H2C···S2#1
N2-H2D···S1
N2-H2D···S2
C2-H2B···S2
C6-H6A···S1
3.3570(19)
3.499(2)
2.75
2.53
3.3423(18)
3.4018(18)
3.040(2)
2.65
2.49
2.48
3.030(2)
Symmetry transformations used to generate equivalent atoms: #1 -x+1,-y+1,-z+1

ACCEPTED MANUSCRIPT
(
a)
(b)
+
−
Fig. 1. UV-Vis absorption spectra of C H N ·C H NS (MPMP) and interaction with
different metal ions (a) Co , Cu +, Mn , Ni , Zn (b) Cu , Fe , Fe , Cr and Hg in
MeOH.
6
14
7
12
2+
2
2
+
2
2+
2+
+
2+
3+
3+
2+
(a)
(b)
Fig. 2. Colour change of MPMP in presence of different metal ions to show the sensing
behaviour

ACCEPTED MANUSCRIPT
+
−
2
-5
Fig. 3. Emission spectrum of C H N ·C H NS in MeOH at 10 M is displayed in black,
6
14
7
12
excitation wave length was 287 nm. Corresponding excitation spectrum is shown in red.
+
̶
Fig. 4. Molecular structure of C H N ·C H NS
2
6
14
7
12
+
−
Fig. 5. Molecular packing of C H N ·C H NS viewed along the c axis. Dashed lines
6
14
7
12
2
indicate piperidinium N-H···S carbodithioate interactions

ACCEPTED MANUSCRIPT
+
−
Fig. 6. The cyclic voltammograms obtained for C H N ·C H NS at different scan rates
6
14
7
12
2
+
−
-1
Fig. 7. The cyclic voltammogram obtained for C H N ·C H NS at 20 mVs scan rates
6
14
7
12
2

ACCEPTED MANUSCRIPT
Research Highlights
•
•
•
•
•
Crystal structure of an ionic compound piperidinium-carbodithioate is reported.
+
¯
2
The compound consists of C H N cation and C H NS anion pair.
6
14
7
12
Cyclic voltammetric study of the compound shows quasi-reversible redox behaviour.
2
+
+
2+
2+
The compound showed interesting red shifts with Co , Cu , Cu and Ni ions.
Inter and intramolecular N–H···S contacts link cation-anion pairs.

ACCEPTED MANUSCRIPT
Graphical Abstract (Synopsis)
The
ionic
compound
4-methyl-piperidinium
4-methyl-piperidinecarbodithioate
+
¯
C H N ·C H NS has been synthesized from the one pot reaction of 4-methylpiperidine
6
14
7
12
2
and carbon disulfide. The asymmetric unit of the compound consists of 4-methyl-
piperidinium cation and 4-methyl-piperidinecarbodithioate anion which are linked via inter
and intramolecular N–H···S contacts. The compound is well characterized on the basis of IR,
NMR, UV-visible and single crystal X-ray diffraction data. The behaviour of the compound
2
+
+
in different metal ion solutions is studied and it shows interesting red shifts with Co , Cu ,
2
+
2+
+
¯
2
Cu and Ni ions which suggests that C H N ·C H NS may be useful in sensing of
6
14
7
12
these ions in solution. Cyclic voltammetric analysis of the compond exhibits quasi-reversible
redox behaviour.