Five-component trigonal nanoprism with six dynamic corners

Article abstract of DOI:10.1039/c7cc04078d

The metallo-supramolecular trigonal prism P is based on five different components and three unlike dynamic coordination motifs: the heteroleptic phenanthroline-terpyridine complex [Zn(1)(4)]²⁺ (HETTAP), the heteroleptic phenanthroline-pyridine

Full text of DOI:10.1039/c7cc04078d

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Marilyn M. Olmstead, Alan L. Balch, Josep M. Poblet, Luis Echegoyenet al.
Reactivity differences of Sc3N@C2n (2n 68 and 80). Synthesis of the
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Five-component trigonal nanoprism with six dynamic corners
Sudhakar Gaikwad, Manik Lal Saha, Debabrata Samanta and Michael Schmittel*
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
www.rsc.org/
The metallo-supramolecular trigonal prism P is based on five different dynamic coordination motifs requires non-interfering
different components and three unlike dynamic coordination binding algorithms to prevent the formation of alternative 2D
motifs: the heteroleptic phenanthroline-terpyridine complex and 3D assemblies.15 For this purpose, we capitalised on the
[Zn(1)(4)]2+ (HETTAP), the heteroleptic phenanthroline-pyridine HETTAP (HETeroleptic Terpyridine And Phenanthroline)16 and
complex [Cu(2)(5A)]+ (HETPYP-I), and the pyridine → zinc(II)- HETPYP-I (HETeroleptic PYridine and Phenanthroline-I)17 algo-
porphyrin interaction.
rithms, which are fully orthogonal to each other18 if properly
instructed, as well as on the well-known pyridine zinc(II)
porphyrin (Npy ZnPor) interaction. To avoid any interference
between the Npy ZnPor
[Cu(phen)]+ (=HETPYP-I)17 and Npy
→
Nature combines structurally different components to develop
functional three-dimensional assemblies that have inspired
chemists to design, synthesise and study artificial heteroleptic
assemblies through self-sorting.1-4 While most of them repre-
sent two-dimensional objects, the state-of-art being defined
by seven-component assemblies,5,6 recently Clever7 and
Crowley8 independently reported on sophisticated 3D hetero-
leptic coordination cages comprising three different compo-
nents. Furthermore, Nitschke identified the unprecedented
guest(G)-induced transformation of the three-component ho-
→
→
→
motifs, we selected 2,6-lutidine and pyridine. 2,6-Lutidine has
a weak binding to ZnPor (log K = 1.82 in DCM to zinc(II)
tetraphenylporphyrin)19 and thus is not able to compete with
the parent pyridine ligand (log K = 3.78) at ZnPor.19
To investigate the fidelity of self-sorting, equimolar quan-
tities of ligands
heated to reflux for 3 h. The selective formation of complexes
C1
C2 and C3, as verified by 1H‒NMR (Figure 1 and Scheme 1)
1‒5
, Cu+ and Zn2+ in CH2Cl2‒CH3CN (1:3) were
,
mometallic G
coordination cage G
⊂
FeII L6 into the four-component heterometallic
4
and for C1 and C2 by electrospray ionisation mass spectroscopy
(ESI‒MS), is guided by maximum site occupancy20 and coordi-
nation preferences of the metal ions (Figure S52, ESI†).18,21
⊂
CuIFeII L4 after addition of copper(I)
2
ions.9 As there is a lot of interest to increase the number of
components for implementing intricate functions in supra-
molecular 3D assemblies that go beyond guest complexation,
such as demonstrated in multi-component rotors,10-12 we are
inspired to push the limits of 3D multi-component assembly.
Increasing the number of components in a dynamic self-
assembly process, however, means that also the number of
counter-productive interactions is augmented often leading to
undesired chemical species.13 Benefiting from our experience
with multi-component self-assembly,5,6,14 we report herein on
the synthesis of a five-component heterometallic supra-
molecular trigonal prism that encompasses six dynamic
cornerstones using three different coordination motifs.
Formation of the strong HETTAP complex C1 = [Zn(
due to additional dipole interactions between the –OMe group
and Zn2+ (log 1418). The complexes [Cu( )(5A)]+ and C3
[( )(5B)] are formed preferably over [Cu( )(5A)]
)(5B)]+ and [(
1)(4
)]2+ is
β
≅
2
=
3
2
3
To construct a five-component trigonal prism with three
Center of Micro and Nanochemistry and Engineering, Organische Chemie I,
Universität Siegen, Adolf-Reichwein-Str. 2, D-57068 Siegen, Germany
E-mail: schmittel@chemie.uni-siegen.de; Tel: +49(0) 2717404356
Electronic Supplementary Information (ESI†) available: Synthetic procedures,
compound characterisations, NMR and ESI-MS spectra and UV-vis titrations. See
DOI: 10.1039/x0xx00000x
Scheme 1. Representation of 3‒fold completive mixture of complexes C1, C2 and C3
self-sorted from eight components.
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deprotected under aqueous basic conditions in THF / MeOH to
CDHCl2
5 6
furnish compound 15 in good yield.
B'
3 8
7 4
F D
Synthesis of 2,6-lutidine segment 17 was accomplished by
25
treating 4-ethynyl-2,6-dimethylpyridine (5A
of 1626 in presence of Pd(0) as a catalyst in a mixture of DMF,
benzene and triethylamine. Finally, the terminal alkyne 15 was
reacted with 4.0 equiv of aryl iodide 17 in DMF and triethyl-
C
A
B
E
(A)
)
with 5.0 equiv
4' 7'
3' 8'
R' O'
N
5' 6'
Ph
(B)
(C)
Ph
β
''
β
'
α'
amine at 80 °C affording the desired panel
6 in 32% yield
(Scheme 3A). Synthesis of the bipyridine pillar 727 was
achieved in 89% yield by treating 4-ethynylpyridine hydrochlo-
ride and 16 under optimised reaction conditions (Scheme 3B).
(D)
9.4
9.0
8.6
8.2
7.8
7.4
7.0
6.6
6.2
5.8
5.4
5.0
4.6
4.2
Figure 1. Partial 1H NMR spectra (400 MHz, 298 K, CD2Cl2:CD3CN, v/v, 9:1) for
comparison (A) C1, (B) C2, (C) C3 and (D) equimolar mixture of 1, 2, 3, 4, 5A, 5B,
[Cu(MeCN)4]B(C6F5)4 and [Zn(OTf)2] = C.
The synthesis of pillar 8 was completed in three steps.
Arene 1928 was subjected to iodination by reaction with iodine
monochloride in MeOH to furnish compound 20 28
. Afterwards,
phenanthroline 2129 was cross-coupled with 20 in presence of
Pd(0) as a catalyst to yield 22, which was reacted with
(Figure S32, ESI†) because of (i) the sterically inhibited binding
of lutidine 5A to ZnPor and (ii) the strong binding of lutidine 5A
to [Cu(
to that of 5B to [Cu(
After these model studies, we designed the dynamic five-
component supramolecular prism (Scheme 2) making use of
the three different coordination motifs and molecular model-
ling (vide infra): prism comprises twice (i) the C1 (HETTAP),
(ii) the C2 (HETPYP-I), and (iii) the C3 (Npy ZnPor) motifs.
As building blocks for , we conceived the trisubstituted
panel (Scheme 3A) with its three distinct binding sites, i.e.
the ZnPor, terpyridine and 2,6-lutidine terminals. The two
pillars and were designed for complexation at the respect-
tive corners (C1 C2 and C3-type) of ligand (Scheme 3B,C).
For affixing the different coordination terminals to panel
we decided to sequentially connect the terpyridine, ZnPor and
2,6-lutidine units to 1,3,5-tribromobenzene ( ) by applying a
2
)]+ (log K = 4.50 in DCM, ESI†, Figure S54) as compared
2
)]+ (log K = 3.00 in DCM).18
P
P
→
P
6
7
8
,
6
6,
9
series of Pd-catalysed Sonogashira cross-coupling reactions.
Initially, the reaction of trimethylsilylacetylene with 5.0 equiv
of
9
in triethylamine afforded the mono-coupled product 1022
in 87% yield. Thereafter, the ethynyl-substituted terpyridine
1123 and zinc porphyrin 1324 were sequentially reacted with
dibromo compound 10 by applying standard Sonogashira
cross-coupling conditions to yield the ZnPor-terpyridine hybrid
14 in 75% yield (over two steps). Compound 14 was then
Scheme 3. (A) Synthesis of tris-substituted ligand
(C) ligands
6, (B) synthesis of ligands 7 and
8.
Scheme 2. Five-component nanoprism
2 | J. Name., 2012, 00, 1-3
P.
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phenanthroline 2330 in DMF and triethylamine at 60 °C
8
being upfield shifted from δ = 6.25 to 5.61 ppm collectively
corroborate the formation of the HETTAP corner, (ii) the slight
)2]X2Y4 (X = downfield shifts of mesityl protons q'-H and t'-H of ligand
OTf), which represents prism from δ = 6.97 and 6.95 to 6.90 and 6.86 ppm reveal the forma-
)2]X2Y4 without pillar between the two zinc tion of the HETPYP-I corner, and (iii) the broad singlets at δ =
porphyrin sites (Scheme 4A). Ligands , Zn(OTf)2 and 6.14 (ββ-H) and 3.65 ppm (αα-H) suggest sandwich type com-
[Cu(CH3CN)4]B(C6F5)4 were thus refluxed for 3.5
CH3CN/DCM (v/v, 3:1) furnishing in 95% yield.
furnishing pillar
At first, we prepared tweezer
B(C6F5)4;
[Zn2Cu2(
8
in 86% yield (Scheme 3C).
T
= [Zn2Cu2(
6)2(
8
8
Y
=
P
=
6
)2(
7
)(
8
7
6, 8
h
in plexation of ligand
(Scheme 2).
7 between two ZnPor units of two panels 6
T
In the UV-vis spectrum of
P (in DCM), the Soret band is
situated at 428 nm, which confirms the presence of C3-type
complexaꢀon units (ESI†, Figure S55).32 As the Soret band of
C3 shows a shoulder when the complex is partially dissociated,
the shoulder-free absorption band of
P at 428 nm indicates a
fully closed prism structure (ESI†, Figure S55). In addition 1H-1H
COSY and diffusion-ordered spectroscopy (DOSY) NMR corro-
borate the formation of the intact trigonal prism with a single
Scheme 4. (A) Synthesis of four-component tweezer T and (B) five-component
supramolecular nanoprism P. Anions: X = B(C6F5)4; Y = OTf.
diffusion coefficient of D = 3.1 × 10–10 m2 s–1 (r
~ 17.1 Å, ESI†,
After evaporation of the solvents, tweezer T was analysed by
1H, 1H–1H COSY NMR, UV-vis and ESI‒MS spectroscopy. The
1
diagnostic H NMR signals of terpyridine protons a-H, b-H and
Figure S40). Without any further purification the resultant
greenish-purple solution was then characterised by ESI‒MS
spectroscopy. The ESI-MS data of the mixture exhibit signals at
c-H of
7.66, 7.52 and 8.32 ppm, respectively, together with an upfield
shift of proton b -H of ligand from δ = 6.25 to 5.60 ppm
6 are shifted from δ = 8.73, 7.39 and 7.92 ppm to δ =
1298.3 and 1403.8 Da denoting [Zn2Cu2(
[Zn2Cu2( )2( )(
)2 B(C6F5)4]5+, respectively, providing strong evi-
dence for the formation of nanoprism (Figure 3), while other
signals (e.g. at 1231.2 Da) are derived from fragmentation of
The MM+-minimised
(Figure 4) shows a slightly distorted
prism structure because the pillars and have a different
length so that both panels are slightly tilted against each
6)2(7)(8
)2(OTf)]5+ and
6
7 8
ꞌ
8
P
crisply confirming the formation of HETTAP complex (Figure 2B
and ESI†, Figures S36 and S37).31 The ESI‒MS of the final
reaction mixture exhibits peaks at 1576.2 and 1231.3 Da that
correspond to [Zn2Cu2(6)2(8
)2]6+ with two or one counter
P.
P
7
8
6
anion(s), respectively (ESI†, Figure S53). The experimental
isotopic splitting pattern of the peak at 1231.3 Da is in good
agreement with the theoretical isotopic splitting.
other: the Cu+(HETPHEN)-Zn2+(HETTAP) distance is 1.77/1.79
nm, the ZnZnPor-ZnZnPor distance is 2.05 nm (ESI†, Figure S41).
Table 1. Comparison of selected 1H NMR chemical shifts (CD2Cl2:CD3CN = 9:1, 400 MHz,
298 K) of model complexes C1, C2 and C3 with prism P. C = C1+C2+C3. For complete
data see ESI†.
Terpyridine-
H
Dimesityl
Phen-H
Trimethoxyphenyl-
Phen-H
Pyridine
λmax
/nma
α’/αα β’/ββ
Unit
A/a
7.67
–
B/b
7.55
–
O’/t’ R’/q’
B’/b’
5.61
–
7
9.00
–
4
8.96
–
C1
C2
C3
6/8
C
–
6.95
–
–
6.95
–
–
–
–
–
–
–
–
–
–
–
–
427
421b
426
421
428
4.25
–
6.55
–
8.73b 7.39b 6.95c 6.97c 6.25c 8.46c 8.27c
Figure 2. Partial 1H NMR spectra (400 MHz, CD2Cl2:CD3CN, v/v, 9:1, 298 K) for
comparison: (A) prism P. (B) tweezer T.
7.62
7.66
7.67
7.49
7.52 6.80
7.53 6.86
6.96
6.96
6.87
6.90
5.58
5.60
5.61
8.96
8.96
9.00
8.94
8.94
8.98
4.20
–
6.58
–
T
P
3.65
6.14
a Absorption maximum of Soret band. b Ligand
6
.
c Ligand
8.
Although formation of tweezer
not fully completive, we decided to implement it into the one-
pot synthesis of (Scheme 4B), expecting that the prism would
profit from cooperative effects. Indeed, a ꢀtraꢀon (ESI†, Figure
S57) revealed a strong binding of to tweezer (log K = 9.29 ±
0.04). All components ( , [Cu(CH3CN)4]B(C6F5)4 and
T as a subpart of prism P was
[Zn2Cu2(6)2(8)2(OTf)2]4+
P
[Zn2Cu2(6)2(8)2(OTf)]5+
1231.2
1575.5
100
1298.3
[Zn2Cu2(6)2(7)(8)2(OTf)]5+
7
T
[ZnCu(6)(8)]3+
6, 7, 8
1001.2
75
50
1741.9
Zn(OTf)2 were thus mixed in a 2:1:2:2:2 ratio and refluxed for
3.5 h (4:1, v/v, CH3CN/DCM). After evaporation of the solvents,
the resultant mixture was analysed by 1H, 1H-1H COSY,
diffusion-ordered (DOSY) NMR and ESI‒MS spectroscopy. The
presence of all three complexation motifs C1-C3 in the
metallo-supramolecular nanoprism was confirmed on the basis
[ZnCu(6)(7)(8)(OTf)]2+
[Zn2Cu2(6)2(7)(8)2B(C6F5)4)]5+
1403.8
25
1
of H‒NMR spectroscopy (Table 1, ESI†, Figures S38, S39). For
200
400
600
800
1000 1200 1400 1600 1800 2000
instance, (i) the characteristic downfield shifts of terpyridine
m/z
protons b-H, c-H and d-H (ligand
6) from δ = 7.39, 7.92 and
Figure 3. ESI-MS spectra of P = [Zn2Cu2(
= 9:1.
6
)2(
7)(
8)2](B(C6F5)4)2(OTf)4 in DCM:CH3CN
8.69 to 7.53, 8.32 and 8.78 ppm, and the upfield shift of a-H
from δ = 8.73 to 7.67 ppm together with proton bꞌ-H of ligand
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15 M. Schmittel, Chem. Commun., 2015, 51, 14956.
16 M. Schmittel, V. Kalsani, R. S. K. Kishore, H. Cölfen and J. W.
Bats, J. Am. Chem. Soc., 2005, 127, 11544.
17 S. Neogi, G. Schnakenburg, Y. Lorenz, M. Engeser and M.
Schmittel, Inorg. Chem., 2012, 51, 10832.
18 M. L. Saha, J. W. Bats and M. Schmittel, Org. Biomol. Chem.,
2013, 11, 5592 .
19 C. H. Kirksey, P. Hambright and C. B. Storm, Inorg. Chem.,
1969, 8, 2141.
20 R. Krämer, J.-M. Lehn and A. Marquis-Rigault, Proc. Natl. Acad.
Sci. U. S. A., 1993, 90, 5394.
21 E. A. Medlycott and G. S. Hanan, Chem. Commun., 2007, 4884.
22 W. Zhao, L. Huang, Y. Guan and W. D. Wulff, Angew. Chem. Int.
Ed. 2014, 53, 3436.
Figure 4. MM+ minimised structure of
P.
23 C. Haensch, M. Chiper, C. Ulbricht, A. Winter, S. Hoeppener and
U. S. Schubert, Langmuir, 2008, 24, 12981.
24 W. J. Youngblood, D. T. Gryko, R. K. Lammi, D. F. Bocian, D.
Holten and J. S. Lindsey, J. Org. Chem., 2002, 67, 2111.
25 D. Winkelhaus, B. Neumann, H.-G. Stammler and N. W. Mitzel,
Dalton Trans., 2012, 41, 9143.
26 M. S. Yusubov, T. V. Funk, K.-W. Chi, E.-H. Cha, G. H. Kim, A.
Kirschning and V. V. Zhdankin, J. Org. Chem., 2008, 73, 295.
27 R. S. K. Kishore, T. Paululat and M. Schmittel, Chem. – Eur. J.
2006, 12, 8136
In conclusion, we have blended three orthogonal binding mo-
tifs, i.e. HETTAP (C1-type), HETPYP-I (C2-type) and py ZnPor
C3-type) complexation to build the dynamic heterometallic
→
(
(M2M’2L2L’2L’’) nanoprism
P. This five-component assembly
adds a new facet to the large family of trigonal two-
component (M2L3),33 (M3L2),34 (M6L2)35 or (M6L3),36 three-
component (M3L2L’6)37 or (M6L2L’3)38 and four-component
(M6L3L’2L’’)39 prisms.40 To the best of our knowledge, the
assembly
P is the first five-component heterometallic supra-
28 C. Villegas, M. Wolf, D. Joly, J. L. Delgado, D. M. Guldi and N.
Martín, Org. Lett., 2015, 17, 5056.
29 M. Schmittel, C. Michel, A. Wiegrefe and V. Kalsani, Synthesis,
2001, 10, 1561.
molecular nanoprism with three different dynamic corners.
Such heteroleptic structures should allow tailoring of smart
compartments for selective reactions and extractions.41
30 A. Goswami, I. Paul and M. Schmittel, Chem. Commun., 2017,
53, 5186.
31 Derived from H NMR integration of mesityl protons of ligand 8
and mesityl protons of porphyrin unit of ligand 6.
32 M. Schmittel, S. De and S. Pramanik, Angew. Chem. Int. Ed.,
2012, 51, 3832.
33 S. Ghosh and P. S. Mukherjee, Organometallics, 2008, 27, 316.
34 M. Stickel, C. Maichle-Moessmer and H. A. Mayer, Eur. J. Inorg.
Chem., 2014, 518.
We are indebted to the DAAD (Deutscher Akademischer
Austauschdienst), DFG (Deutsche Forschungsgemeinschaft,
Schm 647/20-1) and Universität Siegen for financial support.
1
Notes and references
1
2
Z. He, W. Jiang and C. A. Schalley, Chem. Soc. Rev., 2015, 44,
779.
M. L. Saha and M. Schmittel, Org. Biomol. Chem., 2012, 10,
4651.
35 S. Shanmugaraju and P. S. Mukherjee, Chem. - Eur. J., 2015, 21,
6656.
36 (a) S. Bivaud, S. Goeb, J.-Y. Balandier, M. Chas, M. Allain and M.
Sallé, Eur. J. Inorg. Chem., 2014, 2440. (b) D. Samanta and P. S.
Mukherjee, Dalton Trans., 2013, 42, 16784. (c) A. K. Bar, S.
Mohapatra, E. Zangrando and P. S. Mukherjee, Chem. - Eur. J.,
2012, 18, 9571.
37 (a) M. Ikeda, K. Ohno, Y. Kasumi, S. Kuwahara and Y. Habata,
Inorg. Chem., 2014, 53, 24. (b) B. Icli, E. Sheepwash, T. Riis-
Johannessen, K. Schenk, Y. Filinchuk, R. Scopelliti and K. Severin,
Chem. Sci., 2011, 2, 1719.
3
4
K. Osowska and O. Š. Miljanić, Synlett, 2011, 12, 1643.
M. M. Safont-Sempere, G. Fernández and F. Würthner, Chem.
Rev., 2011, 111, 5784.
5
6
7
8
9
N. Mittal, M. L. Saha and M. Schmittel, Chem. Commun., 2015,
51, 15514.
M. L. Saha and M. Schmittel, J. Am. Chem. Soc., 2013, 135,
17743.
W. M. Bloch,Y. Abe, J. J. Holstein, C. M. Wandtke, B. Dittrich and
G. H. Clever, J. Am. Chem. Soc., 2016, 138, 13750.
D. Preston, J. E. Barnsley, K. C. Gordon and J. D. Crowley, J. Am.
Chem. Soc. 2016, 138, 10578.
38 (a) B. M. Schmidt, T. Osuga, T. Sawada, M. Hoshino and M.
Fujita, Ang. Chem. Int. Ed., 2016, 55, 1561. (b) T. Wu, Y.-J. Lin
and G.-X. Jin, Dalton Trans., 2013, 42, 82.
D. M. Wood, W. Meng, T. K. Ronson, A. R. Stefankiewicz, J. K. 39 M. Schmittel, B. He and P. Mal, Org. Lett., 2008, 10, 2513.
M. Sanders and J. R. Nitschke, Angew. Chem. Int. Ed. 2015,
54, 3988.
10 S. K. Samanta and M. Schmittel, J. Am. Chem. Soc., 2013,
135, 18794.
11 S. K. Samanta, J. W. Bats and M. Schmittel, Chem. Commun.,
2014, 50, 2364.
40 (a) T. R. Cook and P. J. Stang, Chem. Rev., 2015, 115, 7001. (b)
Y.-F. Han, W.-G. Jia, W.-B. Yu and G.-X. Jin, Chem. Soc. Rev.,
2009, 38, 3419.
41 P. Howlader, P. Das, E. Zangrando and P. S. Mukherjee, J. Am.
Chem. Soc., 2016, 138, 1668.
12 S. K. Samanta, A. Rana and M. Schmittel, Angew. Chem. Int.
Ed., 2016, 55, 2267.
13 E. R. Draper and D. J. Adams, Nat. Chem. 2016, 8, 737.
14 M. L. Saha and M. Schmittel, Inorg. Chem., 2016, 55, 12366.
4 | J. Name., 2012, 00, 1-3
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