Short and Linear Intermolecular Tetrel Bonds to Tin. Cocrystal Engineering with Triphenyltin Chloride

Article abstract of DOI:10.1021/acs.cgd.9b01681

Group 14 (tetrel) elements potentially provide a region of low electronic density (σ-hole) and elevated electrostatic potential, which acts as an electrophilic site to form attractive interactions with electron-rich moieties. Tetrel bonds are the result of net attractive interaction between an electrophilic region associated with a tetrel atom in a molecular entity and a nucleophilic region in another, or the same, molecular entity. Here, we describe a systematic study of the potential utility of tetrel bonds to tin for engineering novel cocrystalline architectures. We report the preparation of 10 new tetrel-bonded cocrystals of triphenyltin chloride with various Lewis bases featuring oxygen and nitrogen electron donor atoms. Single-crystal X-ray diffraction studies reveal that the formation of short and directional Sn···O and Sn···N tetrel bonds along the extension of the Cl-Sn covalent bond is chiefly responsible for the self-assembly of the two complementary components. Normalized contact parameters of approximately 0.6, tetrel bond angles of approximately 170-180°, and lengthening of the covalent Sn-Cl bond by 6-9% upon cocrystallization are all characteristic of the observed tetrel bonds to tin. Substantial changes in the isotropic ¹¹⁹Sn chemical shifts suggest the persistence of the tin tetrel bond in solution.

Full text of DOI:10.1021/acs.cgd.9b01681

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Article
Short and Linear Intermolecular Tetrel Bonds to Tin. Cocrystal
Engineering with Triphenyltin Chloride
Published as part of a Crystal Growth and Design virtual special issue on Crystalline Molecular Materials: From
Structure to Function
Vijith Kumar, Carl Rodrigue, and David L. Bryce*
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ABSTRACT: Group 14 (tetrel) elements potentially provide a
region of low electronic density (σ-hole) and elevated electrostatic
potential, which acts as an electrophilic site to form attractive
interactions with electron-rich moieties. Tetrel bonds are the result
of net attractive interaction between an electrophilic region
associated with a tetrel atom in a molecular entity and a
nucleophilic region in another, or the same, molecular entity.
Here, we describe a systematic study of the potential utility of
tetrel bonds to tin for engineering novel cocrystalline architectures.
We report the preparation of 10 new tetrel-bonded cocrystals of triphenyltin chloride with various Lewis bases featuring oxygen and
nitrogen electron donor atoms. Single-crystal X-ray diffraction studies reveal that the formation of short and directional Sn···O and
Sn···N tetrel bonds along the extension of the Cl−Sn covalent bond is chiefly responsible for the self-assembly of the two
complementary components. Normalized contact parameters of approximately 0.6, tetrel bond angles of approximately 170−180°,
and lengthening of the covalent Sn−Cl bond by 6−9% upon cocrystallization are all characteristic of the observed tetrel bonds to tin.
Substantial changes in the isotropic 119Sn chemical shifts suggest the persistence of the tin tetrel bond in solution.
the donor atom increases the latter’s Lewis acidity and
consequently the overall bond strength.
INTRODUCTION
■
Research into noncovalent interactions beyond traditional
hydrogen bonds1 and the now well-known π−π,2 cation−π,3
anion−π,4 and aurophilic bonds5 continues apace. The σ-hole
concept6 has led to the discovery and rediscovery7 of several
additional classes of element-based electrophilic interactions.8
σ-hole interactions are of particular fundamental and applied
interest due to the tunability of their strength and their robust
directionality. The halogen bond (XB) is the now prototypical
example of a σ-hole interaction.9 It is now established that
elements of groups 14, 15, and 16 of the periodic table may act
as electrophilic sites and form attractive interactions with
electron-rich partners, giving rise to tetrel,10,11 pnictogen,12,13
and chalcogen bonds,14−16 respectively. All of these σ-hole
bonds, along with hydrogen bonds, may be described
qualitatively using a simple AX···B motif, where X bears
the electrophilic site (bond donor atom) and B designates the
Lewis base center (bond acceptor atom). The strength of the
σ-hole interaction scales with the polarizability of the donor
atom, and the atomic polarizability increases down each group
of the periodic table,17 e.g., C < Si < Ge < Sn < Pb for the
group 14 elements (C = 11.5 au, Si = 38.1 au, Ge = 40.3 au,
and Sn = 55.6 au; au = atomic units). Furthermore, the
presence of an electron-withdrawing substituent (A) bonded to
Mani and Arunan suggested that the carbon atom could act
as an electrophilic center, which can interact noncovalently
with nucleophilic atoms, leading to “carbon bonding”18 by
using Atoms In Molecule (AIM) theoretical calculations; this
idea was substantiated via experimental charge density analysis
by Guru Row and co-workers.19 Frontera and co-workers
coined the term tetrel bonding (TB) within the context of σ-
hole interactions to describe the tendency of heavier tetrel
atoms to interact with electron-rich groups.10 An official
IUPAC definition to describe such inter-/intramolecular
interactions formed by the tetrel atoms, wherein the Group
14 element is the electrophilic site, is currently being
discussed.20 A useful working definition, which follows from
those established for the halogen bond21 and the chalcogen
bond,22 is as follows: tetrel bonds are the result of net
attractive interaction between an electrophilic region asso-
Received: December 17, 2019
Revised: January 13, 2020
Published: January 28, 2020
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ciated with a tetrel atom in a molecular entity and a
nucleophilic region in another, or the same, molecular entity.
Recently, tetrel bonding has received much attention due to
its stabilizing role in SN2 reactions.23 A survey of the recent
literature reveals there are a number of theoretical and
experimental works describing the ability of the lighter tetrels
carbon24,25 and silicon26,27 to act as electrophilic sites, whereas
experimental investigations of the heavier group 14 elements
such as tin, germanium, and lead are relatively limited and less
systematic.28 We note the recent work of Baker and co-workers
which describes the construction of supramolecular assemblies
via the rational utilization of Sn···O tetrel bonds involving a
series of tin complexes of the Schiff’s base salicylaldehyde
acyldihydrazone with a methylene spacer.29 We have
previously reported a solid-state NMR spectroscopy and X-
ray diffraction study of tetrel bonds to lead in a series of lead
coordinated nicotinoyl hydrazine metal organic frameworks.30
However, ultimately Scilabra et al. noted in 2018 that “to the
best of our knowledge, [experimental studies of TBs] have
never focused on interactions involving germanium or tin.”28
There is a substantial body of computational work examining
tetrel bonds to Sn and Ge.31−43 It is in this context that we
report here the design and preparation of 10 new cocrystals of
triphenyltin chloride (1, see Figure 1) with a series of Lewis
discussed. The normalized contact parameter, Nc, is defined as
the ratio of the distance between the two atoms involved in the
interaction to the sum of their van der Waals radii.
Aromatic N-oxides, molecules possessing carbonyl and
sulfoxide moieties, and nitrogen-containing heterocycles were
considered as TB acceptors (Figure 2). The complexes were
Figure 2. Molecular structures of the tetrel bond acceptor molecules
used in this study.
prepared by refluxing TPTCl and Lewis bases in anhydrous
dichloromethane or ethanol under argon and dried under
reduced pressure (see Supporting Information (SI)). The
amount of TB acceptor added was chosen to result in
equimolar numbers of TB donor and acceptor atoms. Single
crystals suitable for X-ray diffraction were obtained by
redissolving the solid material in a combination of solvents
such as ethanol/dichloromethane (1:1) or in pure anhydrous
dichloromethane at 0−5 °C, and allowing slow evaporation of
the solvents (see SI). Complex formation is preliminarily
confirmed by PXRD analysis (see Figure 3 for an example;
selected other examples are presented in the SI) and changes
in the melting point of the complex in comparison with pure
individual tectons.
Solid-State Structural Studies of the Tetrel-Bonded
Complexes. The single-crystal X-ray structure of 1 (CSD
entry: TPSNCl) reveals that there are two symmetry
independent molecules present in the asymmetric unit and
that the crystal packing is mainly stabilized by C−H···π and
C−H···Cl hydrogen bonds. Molecular electrostatic surface
potential (MESP) plots were investigated to assess the general
features related to the TB donor ability of 1. ESP maps were
visualized and traced over electron density surfaces with an
isodensity of 0.002 au (electron per bohr3). The Sn atom has
one associated electropositive region positioned along the
extension of the Sn−Cl covalent bond (Figure 1, right).
Because of the electron-withdrawing character of chlorine, the
σ-hole is clearly positive (42.6 kcal/mol). We have observed
similar behavior for chalcogen-based systems, where an
electron-withdrawing nitrile group promotes the formation of
a strong σ-hole on the chalcogen atom along the prolongation
of NC−Se/Te bonds and results in stronger interactions with
electron donors.44
Figure 1. (A) Molecular structure of triphenyltin chloride (TPTCl,
1). (B) Computed electrostatic potential on the 0.002 au molecular
surface of TPTCl. The red region indicates negative charge density,
and blue indicates positive charge density (B3LYP with Def2TZVP,
GaussView 4.1). The most positive region (blue) is along the
extension of a Cl−Sn covalent bond with a maximum value of 42.6
kcal mol−1. The rotated image on the right depicts the view straight
into the σ-hole, with the chlorine atom out of view behind the tin
atom at the center of the molecule.
bases featuring Sn···O and Sn···N tetrel bonds. All the
cocrystals were characterized by single crystal X-ray diffraction
techniques. This work provides new perspectives into the role
of tin tetrel bonds in determining supramolecular architectures
and demonstrates their potential value for crystal engineering
applications.
RESULTS AND DISCUSSION
■
Preparation of the Tetrel-Bonded Complexes. Com-
mercially available triphenyltin chloride was used as a tetrel
bond donor. This simple molecule was chosen as a viable TB
donor based on literature precedent summarized in ref 28,
where intermolecular and intramolecular tetrel-bonded struc-
tures featuring analogous donors including, e.g., 2,6-bis-
(methoxymethyl)phenyl triphenyltin, 2,6-bis(ethoxymethyl)-
phenyl dichlorophenyltin, chloro(trimethyl)tin, and other
triphenyltin derivatives, featuring normalized contacts in the
range of 60−70% of the sum of the van der Waals’ radii, were
X-ray crystallographic parameters and structural refinement
details of the 10 new cocrystals of 1 are tabulated in the
Supporting Information. The relevant intermolecular TB
geometries, including distances (Sn···X; (X = O, N)) and
angles (Cl−Sn···X), are listed in Table 1. The Sn···X bonds are
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Figure 3. Comparison of the experimental PXRD pattern of 1·DPSO obtained by solution crystallization (top, red) and the simulated pattern
generated from the single-crystal X-ray structure (bottom, blue).
Table 1. Summary of the Cl−Sn···A (A = Acceptor) Tetrel Bonding Geometries Observed via SCXRD
a
compound
Cl−Sn···A (Å)
∠Cl−Sn···A (deg)
Cl−Sn···A Nc
Cl−Sn (Å)
ref code
1 (site 1)
1 (site 2)
1·DPSO
1·PPNO (site 1)
1·PPNO (site 2)
1·DPNO
2.315
2.321
2.480
2.512
2.509
2.501
2.509
2.490
2.478
2.506
2.508
2.527
2.468
2.488
2.517
TPSNCL
2.479 (2)
2.328 (3)
2.346 (3)
2.387 (3)
2.366 (2)
2.350 (2)
2.370 (2)
2.367 (3)
2.393 (3)
2.313 (1)
2.452 (3)
2.525 (4)
2.446 (5)
175.82 (4)
176.56 (9)
171.50 (9)
178.20 (7)
177.66 (5)
169.38 (5)
178.94 (5)
175.41 (8)
175.55 (8)
175.90 (4)
175.04 (9)
174.88 (1)
175.18 (1)
0.63
0.59
0.60
0.61
0.60
0.60
0.61
0.60
0.61
0.59
0.63
0.61
0.62
this work
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1·PNO
1·26DMPNO·H2O
1·35DMPNO
1·2MPNO (site 1)
1·2MPNO (site 2)
1·DMU
1·DABCO·MeOH
1·BP·CH2Cl2 (site 1)
1·BP·CH2Cl2 (site 2)
this work
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this work
a
Nc = dSn···A/Σ rvdW, where dSn···A is the distance between Sn and the electron donor atom and where Σ rvdW is the sum of the van der Waals radii of
tin and of the donor atom.
relatively short as quantified by the normalized contact
parameter (Nc). The covalent Sn−Cl bond of 1 lengthens by
6−9% upon cocrystallization (Table 1), consistent with the
formation of a TB to tin. Moreover, the Cl−Sn···X angles are
close to 180°, illustrating the strong directionality of the
observed TB interactions. Data for each cocrystal will be
discussed in further detail below.
Initially, the supramolecular assembly capability of 1,
namely, the ability to form TBs, was tested using pure and
substituted pyridine N-oxides as TB acceptors. Aromatic N-
oxides have been well acknowledged in heterocyclic chemistry
for functionalized pyridine synthesis and for their electronic
push−pull properties.45 Electron-donating and withdrawing
substituents on the aromatic ring can result in different
hybridization states for the oxygen of the N−O group, thereby
allowing for tuning of the complexation behavior of these
molecules toward metals.46 Such molecules have been
successfully utilized as supramolecular building blocks and as
halogen and hydrogen bond acceptors.47,48 With this as
inspiration, we investigated the cocrystallization of TB donor 1
with various ditopic and monotopic methyl substituted
pyridine N-oxide derivatives (see SI for details of crystallization
conditions). Single crystal X-ray analyses confirmed that the
cocrystals obtained featured tetrel bonds between tin and
oxygen (Figure 4). The X-ray structures reveal 1:1 adducts of
new tetrel-bonded systems 1·PNO (PNO = pyridine N-oxide)
and 1·2MPNO (2MPNO = 2-methylpyridine N-oxide) which
crystallize in monoclinic systems with the P21/n space group
and complex 1·35DMPNO (35DMPNO = 3,5-dimethylpyr-
idine N-oxide) which crystallizes in the P2/c space group,
respectively. These cocrystals possess similar interaction
patterns around the tin atoms. The short and directional
Sn···O− (Sn···O− Nc ranges from 0.60 to 0.61, the Cl−Sn···O−
angle ranges from 175.41° to 178.94°) TBs are principally
responsible for the self-assembly of the two components. In
these three structures, the strong linearity of the TB is clear as
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Figure 4. Partial ball and stick representations (Mercury 4.10.2) show the Cl−Sn···O− tetrel bonds in a series of cocrystals containing monotopic
and ditopic pyridine N-oxides. (A) Cocrystal 1·PNO; (B) 1·2MPNO; (C) 1·35DMPNO; (D) 1·PPNO; and (E) 1·DPNO. Color codes: gray,
carbon; blue, nitrogen; white, hydrogen; green, chlorine; dark green, tin; red, oxygen (dashed black lines denote TB).
Figure 5. Partial ball and stick representation (Mercury 4.10.2) show the Cl−Sn···O tetrel bonds with sulfoxide and carbonyl acceptors. (A)
Cocrystal 1·DPSO and (B) cocrystal 1·DMU. Color codes: gray, carbon; blue, nitrogen; white, hydrogen; green, chlorine; dark green, tin; red,
oxygen; yellow, sulfur (dashed black lines denote TB).
quantified by Cl−Sn···O− angles of 177.66°, 175.41°, and
178.94°, respectively.
TPTCl units. The observed TBs are quite short, linear, and
approximately aligned with the Cl−Sn covalent bond in both
cocrystals. The Sn···O− normalized contact is 0.61, and the
Cl−Sn···O− angle is 178.20°.
1·PPNO (PPNO = 4-phenylpyridine N-oxide) crystallizes in
the monoclinic P21/c space group with two molecules in the
asymmetric unit. Similar short and linear tetrel bonds were
observed; the Cl−Sn···O− separations are 2.33 and 2.35 Å (Nc
are 0.59 and 0.60, respectively) with Cl−Sn···O− angles of
176.56° and 171.50°, respectively. In the two symmetry
independent molecules, one of the 4-phenylpyridine N-oxide
molecules is linear, while the other is in a slightly twisted
conformation. We further tested the ditopic TB acceptor, 4′4-
dipyridyl N,N′-dioxide (DPNO) with TB donor 1. The linker
molecule was prepared by oxidation of 4,4-bypyridine
according to the previously reported literature.49 1·DPNO
crystallizes in the monoclinic space group P21/n with Z = 2.
The single-crystal X-ray analysis confirmed the formation of a
tetrel bonded complex and highlighted that the assembly of the
molecules was mainly driven by the Sn···O− synthon where
DPNO acts as a ditopic linker (Figure 4). The dipyridyl
dioxide is positioned on an inversion center and bridges two
A survey of the Cambridge Structural Database shows that
there are a few examples of sulfoxide,50 phosphine oxide,51 and
carbonyl oxygens52 which act as a tetrel bond acceptors. To
test the generality and the robustness of TB toward various
oxygen-containing moieties, we have challenged 1 with
diphenyl sulfoxide and dimethyl urea as TB acceptors.
Tetrel-bonded complexes 1·DPSO and 1·DMU crystallize in
monoclinic systems with P21/c and P21/n space groups,
respectively, with Z = 4 (Figure 5). Once again X-ray analysis
demonstrates the assembly process is mainly driven by Sn···O
close contacts. Specifically, the Sn···O normalized contacts are
0.59 and 0.63, and the Cl−Sn···N angles are 175.90° and
175.82° for 1·DPSO and 1·DMU, respectively.
The ability of amine and pyridine nitrogen atoms to form
close contacts with Sn derivatives is well documented.53,54 The
tetrel-bonded complex 1·BP·CH2Cl2 crystallizes in a triclinic
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crystal system and the P1 space group (Figure 6). There are
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Article
̅
molecules as tetrel bond acceptors is attributed to the potential
steric hindrance associated with the two methyl groups
adjacent to the oxygen atom in the N-oxide moiety. This
appears to be consistent with the findings of Scheiner, who has
examined the influence of steric crowding on the formation of
tetrel bonds using computational chemistry.41 This hydrated
structure is obtained even though it was prepared under
nominally anhydrous conditions. A similar effect is also
observed in the case of the well-known bidentate electron
donor 1,4-diazabicyclo[2.2.2]octane (DABCO). Complex 1·
DABCO·CH3OH cocrystallizes in an orthorhombic system
with the space group Pbca (Z = 8). Because of the small size of
the TB acceptor, there is insufficient space to bring two TPTCl
molecules together; therefore, the crystallization solvent
methanol enters the crystal lattice via Sn···O tetrel bonds
(the Sn···O normalized contact is 0.63, and the Cl−Sn···O
angle is 175.04°). The ditopic acceptor DABCO further
interacts with methanol via O−H···N hydrogen bonds and
bridges the two TPTCl molecules (O−H···N distance 1.763
Å).
two symmetry independent molecules present in the
Figure 6. Partial ball and stick representation (Mercury 4.10.2)
showing Cl−Sn···N tetrel bonds in 1·BP·CH2Cl2. Color codes: gray,
carbon; blue, nitrogen; white, hydrogen; green, chlorine; dark green,
tin; red, oxygen (dashed black lines denote TB, the solvent molecule
was omitted for clarity).
Having demonstrated the role of tetrel bonds to tin in 1 in
the solid state, we used 119Sn NMR to qualitatively assess the
persistence of these interactions in solution. 119Sn chemical
shifts are highly sensitive to changes in the electronic and
structural environments of a molecule. NMR spectra of
selected complexes in CDCl3 shows significant changes in
the 119Sn chemical shift compared to TPTCl (pure 1, δ119Sn:
−44.8 ppm; 1·BP: Δδ 119Sn = −22.7 ppm; 1·DABCO·
CH3OH:Δδ 119Sn = −21.3 ppm; 1·PNO Δδ119Sn = −28.0
ppm; 1·DPSO: Δδ119Sn = −17.6 ppm; 1·DMU: Δδ 119Sn =
−16.8 ppm). A detailed quantum chemical investigation is
underway to characterize the origins of these shifts; however,
they strongly suggest that tetrel bonding to tin persists, at least
to some extent, in solution.
asymmetric unit, and in one of these the bipyridine is located
on an inversion center. The self-assembly process is mainly
driven by Sn···N tetrel bonds; specifically, the Sn···N
normalized contacts are 0.61 and 0.62, and the Cl−Sn···N
angles are 174.88° and 175.18° (Figure 6). The CH2 group in
the solvent molecule engages in H···H and C−Cl···H short
contacts and bridges the neighboring 1·BP molecules. The
interaction features are similar to those seen in the previously
reported 1·BP benzene solvate (CSD entry code FEJFOQ)55
and in the complex of 1 with 1,2-di(4-pyridyl)ethane (CSD
entry code JAGSIU).56
On the basis of the observed Sn···O interactions with various
substituted pyridine N-oxides, we attempted to cocrystallize 1
with 2,6-dimethylpyridine N-oxide (26DMPNO). The result-
CONCLUSIONS
■
ing complex, 1·26DMPNO, crystallizes in the triclinic P1
̅
space
Triphenyltin chloride (1) has been examined as a prototypical
tin tetrel bond donor for crystal engineering applications. X-ray
crystallography and molecular electrostatic surface potential
analyses of pure donor 1 have revealed a region of depleted
electron density along the extension of the Sn−Cl covalent
bond. A series of 10 new cocrystals of 1 featuring tetrel bonds
to tin has been prepared and characterized via single-crystal
and powder X-ray diffraction. These triphenyltin chloride
group with Z = 2. More interestingly, the X-ray structure
demonstrates that water molecules enter into the crystal lattice
via strong Sn···O tetrel bonds (the Sn···O Nc value is 0.60, and
the Cl−Sn···O angle is 169.38°). Further, these water
molecules are hydrogen bonded to two molecules of
26DMPNO (O−H···O distances of 2.716 and 1.821 Å) and
form a tetrameric synthon (Figure 7). The appearance of water
Figure 7. Partial ball and stick representations (Mercury 4.10.2) show the Cl−Sn···O tetrel bonds in (A) 1·26DMPNO·H2O and (B) 1·DABCO·
CH3OH. Color codes: gray, carbon; blue, nitrogen; white, hydrogen; green, chlorine; silver green, tin; red, oxygen (dashed black lines denote TB;
the solvent molecule was omitted for clarity).
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Accession Codes
complexes exhibit moderately strong and directional close
contacts to oxygen and nitrogen. The σ-hole of TB donor 1
thus demonstrates a remarkable ability to promote the
formation of a diversity of supramolecular solid-state
architectures depending on the site selectivity/availability of
the electron donor systems. Normalized contact parameters of
approximately 0.6, tetrel bond angles of approximately 170−
180°, and lengthening of the covalent Sn−Cl bond by 6−9%
upon cocrystallization are all characteristic of the observed
tetrel bonds to tin. Substantial changes in the isotropic 119Sn
chemical shifts suggest the persistence of the tin tetrel bond in
solution.
To conclude, the cocrystalline architectures studied herein
provide new insight into the role of tetrel bonds to tin. These
bonds are strong and highly linear, resulting in the formation of
stable, rigid supramolecular structures with a range of acceptor
groups. In concert with a growing body of literature data,11,28 it
is clear that the TB holds great potential for future crystal
engineering and supramolecular assembly applications. The
present work provides a clear body of experimental evidence
supporting the concepts proffered in the concluding remarks of
Resnati and co-workers,28 i.e., (i) that tin tetrel bonds tend to
be very highly linear and (ii) that steric congestion can
influence the final structures as observed presently in the cases
of 1·26DMPNO·H2O and 1·DABCO·CH3OH, where solvent
molecules intervene to form tetrel-bonded “bridges” between
the tin donor molecules and the intended TB acceptor
molecules.
CCDC 1969055−1969064 contain the supplementary crys-
tallographic data for this paper. These data can be obtained
free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by
emailing data_request@ccdc.cam.ac.uk, or by contacting The
Cambridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336033.
AUTHOR INFORMATION
■
Corresponding Author
David L. Bryce − Department of Chemistry and Biomolecular
Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5,
Canada; orcid.org/0000-0001-9989-796X; Phone: 613-
562-5800; Email: dbryce@uottawa.ca
Authors
Vijith Kumar − Department of Chemistry and Biomolecular
Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5,
Canada
Carl Rodrigue − Department of Chemistry and Biomolecular
Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5,
Canada
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.cgd.9b01681
Notes
The authors declare no competing financial interest.
EXPERIMENTAL SECTION
ACKNOWLEDGMENTS
■
■
Preparation of the Tetrel-Bonded Complexes. In a typical
procedure, triphenyltin chloride (1) and an electron donor were
placed in a round-bottom flask, and ethanol was added. The resulting
solution was refluxed for 1 h under argon. The solution was cooled to
room temperature, and solvent was removed under reduced pressure.
The white solid material was further dissolved in 1:1 diethyl ether/
dichloromethane or diethyl ether/methanol and filtered. The
supernatant was held at 0−5 °C for 48 h to obtain the pure
crystalline tetrel bonded product. Detailed synthetic procedures and
characterization for each cocrystal are described in the SI.
Powder X-ray Diffraction. Data sets were collected on a Rigaku
Ultima IV powder diffractometer at 298 K ( 2) (CuKα1 radiation
with a wavelength of 1.54056 Å). The measurements were carried out
in a focused beam geometry with a step-scan technique over a 2θ
range of 5 to 50°. Data were acquired using a scintillation counter
detector in continuous scanning mode with a step size of 0.02°. The
experimental PXRD patterns of pure 1 and of selected cocrystals, and
simulated patterns generated from the single crystal data, are shown in
Figure 3 and in the SI.
D.L.B. thanks the Natural Sciences and Engineering Research
Council of Canada for funding. V. K., C. R., and D. L. B. are
grateful to Yijue Xu for assistance with the electrostatic surface
potential calculations.
REFERENCES
■
(1) Desiraju, G. R.; Steiner, T. The Weak Hydrogen Bond in
Structural Chemistry and Biology; OUP: Oxford, 1999.
(2) Neel, A. J.; Hilton, M. J.; Sigman, M. S.; Toste, F. D. Exploiting
Non-Covalent π Interactions For Catalyst Design. Nature 2017, 543,
637−646.
(3) Mahadevi, A. S.; Sastry, G. N. Cation−π Interaction: Its Role
and Relevance in Chemistry, Biology, and Material Science. Chem.
Rev. 2013, 113, 2100−2138.
́
(4) Zhao, Y.; Cotelle, Y.; Liu, L.; Lopez-Andarias, J.; Bornhof, A.-B.;
Akamatsu, M.; Sakai, N.; Matile, S. The Emergence of Anion−π
Catalysis. Acc. Chem. Res. 2018, 51, 2255−2263.
(5) Schmidbaur, H.; Schier, A. Aurophilic Interactions as a Subject
of Current Research: An Up-Date. Chem. Soc. Rev. 2012, 41, 370−
412.
Single Crystal X-ray Diffraction. The data were collected on a
Bruker AXS Smart Apex and Kappa Apex diffractometer equipped
with MoKα radiation (wavelength 0.7103 Å) with an APEX II CCD
detector. The raw data collection and processing were performed with
the Bruker APEX II software package. Structure solution, disorder
treatment, and refinement details are provided in the SI.
(6) Politzer, P.; Murray, J. S.; Clark, T. Halogen Bonding And Other
σ-Hole Interactions: A Perspective. Phys. Chem. Chem. Phys. 2013, 15,
11178−11189.
(7) Alcock, N. W. Secondary Bonding to Nonmetallic Elements.
Adv. Inorg. Chem. Radiochem. 1972, 15, 1−58.
ASSOCIATED CONTENT
(8) Cavallo, G.; Metrangolo, P.; Pilati, T.; Resnati, G.; Terraneo, G.
Naming Interactions from the Electrophilic Site. Cryst. Growth Des.
2014, 14, 2697−2702.
■
sı
* Supporting Information
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/acs.cgd.9b01681.
(9) Cavallo, G.; Metrangolo, P.; Milani, R.; Pilati, T.; Priimagi, A.;
Resnati, G.; Terraneo, G. The Halogen Bond. Chem. Rev. 2016, 116,
2478−2601.
Experimental details, synthetic details, experimental and
simulated powder X-ray diffractograms, single-crystal X-
ray data (PDF)
́
(10) Bauza, A.; Mooibroek, T. J.; Frontera, A. Tetrel-Bonding
Interaction: Rediscovered Supramolecular Force? Angew. Chem., Int.
Ed. 2013, 52, 12317−12321.
2032
https://dx.doi.org/10.1021/acs.cgd.9b01681
Cryst. Growth Des. 2020, 20, 2027−2034

Crystal Growth & Design
pubs.acs.org/crystal
Article
́
(11) Bauza, A.; Seth, S. K.; Frontera, A. Tetrel Bonding Interactions
(29) Ullah, H.; Twamley, B.; Waseem, A.; Khawar Rauf, M.; Tahir,
M. N.; Platts, J. A.; Baker, R. J. Tin···Oxygen Tetrel Bonding: A
Combined Structural, Spectroscopic, and Computational Study. Cryst.
Growth Des. 2017, 17, 4021−4027.
At Work: Impact on Tin And Lead Coordination Compounds. Coord.
Chem. Rev. 2019, 384, 107−125.
(12) Lee, L. M.; Tsemperouli, M.; Poblador-Bahamonde, A. I.; Benz,
S.; Sakai, N.; Sugihara, K.; Matile, S. Anion Transport with Pnictogen
Bonds in Direct Comparison with Chalcogen and Halogen Bonds. J.
Am. Chem. Soc. 2019, 141, 810−814.
(30) Southern, S. A.; Errulat, D.; Frost, J. M.; Gabidullin, B.; Bryce,
D. L. Prospects for 207Pb Solid-State NMR Studies of Lead Tetrel
Bonds. Faraday Discuss. 2017, 203, 165−186.
(31) Matczak, P. Assessment of Various Density Functionals for
Intermolecular N→ Sn Interactions: the Test Case of Poly-
(Trimethyltin Cyanide). Comput. Theor. Chem. 2015, 1051, 110−122.
(32) Matczak, P. Theoretical investigation of the N → Sn
coordination in (Me3SnCN)2. Struct. Chem. 2015, 26, 301−318.
(33) Li, Q.-Z.; Zhuo, H.-Y.; Li, H.-B.; Liu, Z.-B.; Li, W.-Z.; Cheng,
J.-B. Tetrel−Hydride Interaction between XH3F (X = C, Si, Ge, Sn)
and HM (M = Li, Na, BeH, MgH). J. Phys. Chem. A 2015, 119,
2217−2224.
(13) Scilabra, P.; Terraneo, G.; Resnati, G. Fluorinated Elements of
Group 15 as Pnictogen Bond Donor Sites. J. Fluorine Chem. 2017,
203, 62−74.
(14) Vogel, L.; Wonner, P.; Huber, S. M. Chalcogen Bonding: An
Overview. Angew. Chem., Int. Ed. 2019, 58, 1880−1891.
(15) Scilabra, P.; Terraneo, G.; Resnati, G. The Chalcogen Bond in
Crystalline Solids: A World Parallel to Halogen Bond. Acc. Chem. Res.
2019, 52, 1313−1324.
(16) Nayak, S. K.; Kumar, V.; Murray, J. S.; Politzer, P.; Terraneo,
G.; Pilati, T.; Metrangolo, P.; Resnati, G. Fluorination Promotes
Chalcogen Bonding in Crystalline Solids. CrystEngComm 2017, 19,
4955−4959.
(34) Marín-Luna, M.; Alkorta, I.; Elguero, J. Theoretical Study of the
Geometrical, Energetic and NMR Properties of Atranes. J. Organomet.
Chem. 2015, 794, 206−215.
(35) Liu, M.; Li, Q.; Cheng, J.; Li, W.; Li, H.-B. Tetrel bond of
pseudohalide anions with XH3F (X = C, Si, Ge, and Sn) and its role in
́
(17) Bauza, A.; Mooibroek, T. J.; Frontera, A. The Bright Future of
Unconventional σ/π-Hole Interactions. ChemPhysChem 2015, 16,
2496−2517.
2
SN reaction. J. Chem. Phys. 2016, 145, 224310.
(36) Scheiner, S. Highly Selective Halide Receptors Based on
Chalcogen, Pnicogen, and Tetrel Bonds. Chem. - Eur. J. 2016, 22,
18850−18858.
(37) Ghara, M.; Pan, S.; Kumar, A.; Merino, G.; Chattaraj, P. K.
Structure, Stability, and Nature of Bonding in Carbon Monoxide
Bound EX3+ Complexes (E = Group 14 Element; X = H, F, Cl, Br, I).
J. Comput. Chem. 2016, 37, 2202−2211.
(38) Liu, M.; Li, Q.; Scheiner, S. Comparison of tetrel bonds in
neutral and protonated complexes of pyridineTF3 and furanTF3 (T =
C, Si, and Ge) with NH3. Phys. Chem. Chem. Phys. 2017, 19, 5550−
5559.
(18) Mani, D.; Arunan, E. The X−C···Y (X = O/F, Y = O/S/F/Cl/
Br/N/P) ‘Carbon Bond’ and Hydrophobic Interactions. Phys. Chem.
Chem. Phys. 2013, 15, 14377−14383.
(19) Thomas, S. P.; Pavan, M. S.; Guru Row, T. N. Experimental
Evidence for ‘Carbon Bonding’ in the Solid State From Charge
Density Analysis. Chem. Commun. 2014, 50, 49−51.
(20) Bryce, D. L.; Desiraju, G. R.; Frontera, A.; Krossing, I; Legon,
A. C.; Nicotra, F.; Rissanen, K.; Scheiner, S.; Terraneo, G.;
Metrangolo, P.; Resnati, G. Categorizing Chalcogen, Pnictogen, and
Tetrel Bonds, And Other Interactions Involving Groups 14−16
Elements. IUPAC Project No.: 2016-001-2-300. https://iupac.org/
projects/project-details/?project_nr=2016-001-2-300.
(21) Desiraju, G. R.; Ho, P. S.; Kloo, L.; Legon, A. C.; Marquardt,
R.; Metrangolo, P.; Politzer, P.; Resnati, G.; Rissanen, K. Definition of
the Halogen Bond (IUPAC Recommendations 2013). Pure Appl.
Chem. 2013, 85, 1711−1713.
(39) Scheiner, S. Systematic Elucidation of Factors That Influence
the Strength of Tetrel Bonds. J. Phys. Chem. A 2017, 121, 5561−5568.
(40) Esrafili, M. D.; Mousavian, P. Strong Tetrel Bonds: Theoretical
Aspects and Experimental Evidence. Molecules 2018, 23, 2642.
(41) Scheiner, S. Steric Crowding in Tetrel Bonds. J. Phys. Chem. A
2018, 122, 2550−2562.
(22) Aakeroy, C. B.; Bryce, D. L.; Desiraju, G. R.; Frontera, A.;
Legon, A. C.; Nicotra, F.; Rissanen, K.; Scheiner, S.; Terraneo, G.;
Metrangolo, P.; Resnati, G. Definition of the Chalcogen Bond
(IUPAC Recommendations 2019). Pure Appl. Chem. 2019, 91, 1889−
1892.
(23) Grabowski, S. J. Tetrel Bond−σ-hole Bond as a Preliminary
Stage of the SN2 reaction. Phys. Chem. Chem. Phys. 2014, 16, 1824−
1834.
(24) Karim, A.; Schulz, N.; Andersson, H.; Nekoueishahraki, B.;
Carlsson, A.-C. C.; Sarabi, D.; Valkonen, A.; Rissanen, K.;
Grafenstein, J.; Keller, S.; Erdelyi, M. Carbon’s Three-Center, Four-
Electron Tetrel Bond, Treated Experimentally. J. Am. Chem. Soc.
2018, 140, 17571−17579.
(25) Southern, S. A.; Bryce, D. L. NMR Investigations of
Noncovalent Carbon Tetrel Bonds. Computational Assessment and
Initial Experimental Observation. J. Phys. Chem. A 2015, 119, 11891−
11899.
(26) Chipanina, N. N.; Lazareva, N. F.; Oznobikhina, L. P.;
Shainyan, B. A. Tetrel Bonding along the Pathways of Transsilylation
and Alkylation of N-Trimethylsilyl-N-methylacetamide with Bifunc-
tional (Chloromethyl)fluorosilanes. J. Phys. Chem. A 2019, 123,
5178−5189.
(27) Taylor, P. G.; Bassindale, A. R.; El Aziz, Y.; Pourny, M.;
Stevenson, R.; Hursthouse, M. B.; Coles, S. J. Further Studies of
Fluoride Ion Entrapment In Octasilsesquioxane Cages; X-Ray Crystal
Structure Studies and Factors That Affect Their Formation. Dalton
Trans. 2012, 41, 2048−2059.
(28) Scilabra, P.; Kumar, V.; Ursini, M.; Resnati, G. Close Contacts
Involving Germanium and Tin in Crystal Structures: Experimental
Evidence of Tetrel Bonds. J. Mol. Model. 2018, 24, 37.
́
(42) Frontera, A.; Bauza, A. S···Sn Tetrel Bonds in the Activation of
Peroxisome Proliferator-Activated Receptors (PPARs) by Organotin
Molecules. Chem. - Eur. J. 2018, 24, 16582−16587.
́
(43) Zierkiewicz, W.; Michalczyk, M.; Wysokinski, R.; Scheiner, S.
Dual Geometry Schemes in Tetrel Bonds: Complexes between TF4
(T = Si, Ge, Sn) and Pyridine Derivatives. Molecules 2019, 24, 376.
(44) Kumar, V.; Leroy, C.; Bryce, D. L. Halide Ion Recognition Via
Chalcogen Bonding in the Solid State and in Solution. Directionality
and Linearity. CrystEngComm 2018, 20, 6406−6411.
(45) Adriaenssens, L.; Ballester, P. Hydrogen Bonded Supra-
molecular Capsules With Functionalized Interiors: The Controlled
Orientation of Included Guests. Chem. Soc. Rev. 2013, 42, 3261−
3277.
(46) Puttreddy, R.; Steel, P. J. 4-Methoxypyridine N-oxide: An
Electron-Rich Ligand That Can Simultaneously Bridge Three Silver
Atoms. Inorg. Chem. Commun. 2014, 41, 33−36.
́
(47) Puttreddy, R.; Topic, F.; Valkonen, A.; Rissanen, K. Halogen-
Bonded Co-Crystals of Aromatic N-oxides: Polydentate Acceptors for
Halogen and Hydrogen Bonds. Crystals 2017, 7, 214.
̈
̈
(48) Puttreddy, R.; Rautiainen, J. M.; Makela, T.; Rissanen, K.
Strong N-X···O-N Halogen Bonds: A Comprehensive Study on N-
Halosaccharin Pyridine N-Oxide Complexes. Angew. Chem., Int. Ed.
2019, 58, 18610−18618.
(49) Toma, O.; Mercier, N.; Allain, M.; Meinardi, F.; Botta, C.
Lead(II) 4,4′-Bipyridine N-Oxide Coordination Polymers − Highly
Phosphorescent Materials with Mechanochromic Luminescence
Properties. Eur. J. Inorg. Chem. 2017, 2017, 844−850.
̈
(50) Reeske, G.; Schurmann, M.; Costisella, B.; Jurkschat, K.
Organotin-Substituted Crown Ethers for Ditopic Complexation of
Anions and Cations. Eur. J. Inorg. Chem. 2005, 2005, 2881−2887.
2033
https://dx.doi.org/10.1021/acs.cgd.9b01681
Cryst. Growth Des. 2020, 20, 2027−2034

Crystal Growth & Design
pubs.acs.org/crystal
Article
(51) Shariatinia, Z.; Mirhosseini Mousavi, H. S.; Bereciartua, P. J.;
Dusek, M. Structures of a Novel Phosphoric Triamide and Its
Organotin(IV) Complex. J. Organomet. Chem. 2013, 745−746, 432−
438.
(52) Lorberth, J.; Shin, S.-H.; Donath, H.; Wocadlo, S.; Massa, W.
Metalorganic diazoalkanes: XX. Crystal Structure of Trimethyltin
Diazoacetic Ester, Me3SnC(N2)CO2Et. J. Organomet. Chem. 1991,
407, 167−171.
(53) Zhu, C.; Yang, L.; Li, D.; Zhang, Q.; Dou, J.; Wang, D.
Synthesis, Characterization, Crystal Structure and Antitumor Activity
of Organotin(IV) Compounds Bearing Ferrocenecarboxylic Acid.
Inorg. Chim. Acta 2011, 375, 150−157.
(54) Ma, C.; Han, Y.; Li, D. Synthesis And Crystal Structures Of
Diorganotin Dicyanoethylene-1,2-Dithiolate Compounds and Their
Derivatives With 4,4′-Bipy or Phen. Polyhedron 2004, 23, 1207−1216.
(55) Ma, C.; Zhang, J.; Zhang, R. Syntheses, Characterizations, and
Crystal Structures of Organotin(IV) Chloride Complexes With 4,4′-
Bipyridine. Heteroat. Chem. 2004, 15, 338−346.
(56) Bajue, S. A.; Lewis, C.; Clarke, K.; Bramwell, F. B.; Patrick, B.
O.; Brock, C. P. Isostructural or Not? Adducts of Some ArylTin
Halides With (E)-1,2-Bis(4-Pyridyl)Ethene. Acta Crystallogr., Sect. C:
Cryst. Struct. Commun. 2003, 59, m207−211.
2034
https://dx.doi.org/10.1021/acs.cgd.9b01681
Cryst. Growth Des. 2020, 20, 2027−2034