Geometrically Complementary Self-Assembly of a Hexarhomboid

8 hours ago - g wave velocity. and height were set as 683 m/s and 26.3 V,. respectively. Data were collected and analyzed by using MassLynx 4.1 and ...
0 downloads 0 Views 2MB Size
Download PDF
Communication pubs.acs.org/IC

Cite This: Inorg. Chem. XXXX, XXX, XXX−XXX

Geometrically Complementary Self-Assembly of a Hexarhomboid Architecture from Two Ruthenium(II)−Organic Building Blocks Jun Wang,†,‡ Xiaobo Xue,†,‡ Mingzhao Chen,*,† Tun Wu,§ Shi-Cheng Wang,⊥ He Zhao,† Zhiyuan Jiang,† Jun Yan,† Zhilong Jiang,§ Yi-Tsu Chan,⊥ and Pingshan Wang*,†,§ †

Downloaded by UNIV OF SOUTHERN INDIANA at 18:01:47:273 on May 31, 2019 from https://pubs.acs.org/doi/10.1021/acs.inorgchem.9b00867.

Department of Organic and Polymer Chemistry, College of Chemistry and Chemical Engineering, Central South University (CSU), Changsha, Hunan 410083, China § Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Institute of Environmental Research at Greater Bay Area, Guangzhou University, Guangzhou 510006, China ⊥ Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan S Supporting Information *

shape, a quadrilateral whose four sides all have the same length. Fujita and Stang have obtained several [2 + 2] rhomboids,32−34 whereas a terpyridine-based rhombus has rarely been reported.35,36 Besides, the multirhomboid polygons were even countable.20,37 Herein, we report a shape-persistent metallosupramolecular multirhomboid (Figure 1), which inlays

ABSTRACT: A shape-persistent metallosupramolecular multirhomboid that inlays a hexarhomboid polygon in a three-lobed flat structure was prepared by means of coordination-driven self-assembly. The key ligands were synthesized by a “reaction on complex” strategy that becomes accessible to troublesome metalloorganic ligand L3. The formation here consists of four different starting components and two metal ions. Complementarity of the shape and size drives molecular puzzling and results in the multicomponent, quantitative self-assembled construct.

C

ontrollable preparation of a distinctive supramolecular structure with precise size and shape has always been the pursuit of scientists. Over the past decades, plenty of design principles have been demonstrated to achieve intricate and functional architectures1−3 and endow them with unique and fascinating property applications, such as in sensing, photoelectricity, catalysis, biomedicine, and energy conversion fields.4−6 Pioneering work on coordination-driven supramolecular constructs was conducted by Lehn et al.,7 Sauvage et al.,8 Stang and Olenyuk,9 and Fujita,10 who reported the formation of a great number of delicate circular helicates, grids, knots, metallomacrocycles, and related species.11−14 In the area of tridentate terpyridyl (tpy) self-assembly chemistry,15−17 Newkome and Moorefield,18,19 Li et al.,20,21 Chan et al.,22,23 and others24−26 have documented plenty of terpyridine-based metallosupramolecules. For the purposes of constructing more intricate shape-persistent architectures, stepwise assembly27,28 and multicomponent self-assembly29,30 have been introduced. However, preparation of the desired and pure target compounds through multicomponent self-assembly is often challenging, and the design of a metalloorganic ligand (MOL) appears important to lead assembly trends.31 Over the years, 2D polygon-based metalloarchitectures have represented an important class of assemblies because the metal−ligand coordination interaction provides a predictable and tenacious connection. In particular, 2D dominates a great number of elegant patterns, such as rhomboids,11 pentagrams,4 hexagrams,24 self-similar fractal sets,19 wreaths,21 etc. In plane Euclidean geometry, the rhombus typically has a diamond © XXXX American Chemical Society

Figure 1. Illustration of a hexarhomboid pattern built from two selfcomplementary multiterpyridines.

a molecular hexarhomboid polygon in a three-lobed flat structure from self-complementary subunits (Scheme 1). Two novel tetratopic MOLs, L2 and L3, were designed and synthesized. In shape, each MOL ligand bears two homologous half-parallelograms and their own two planes could form an open orientation, which could avoid the self-assembly of the ligand itself. More importantly, the complementarity of the ligand shape and size drives molecular puzzling and results in the multicomponent, quantitative-assembled multirhomboid constructs.38−40 Meanwhile, the self-assembly of a multirhomboid was an exiguous example of two types of MOLs that successfully spliced in quantitative yield. The original design involved a sample rhomboid (Scheme 1A) that was assembled by a parallelogram-shape MOL L1 through a one-step methodology. The heteroleptic L1 with two free terpyridines was achieved in 60% yield by a 2-fold coupling reaction of the dibromo-substituted ruthenium(II) compound C1 and 4′-(4-boronophenyl)-terpyridine, where Received: March 26, 2019

A

DOI: 10.1021/acs.inorgchem.9b00867 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry Scheme 1. Syntheses of (A) Rhomboid S1 and (B) Hexarhomboid S2

Figure 2. 1H NMR spectra (500 MHz, 298 K) of (A) L1 in CDCl3 (the asterisk represents the trichloromethane signal peak), (B) rhomboid structure S1 in CD3CN, (C) L2 in CD2Cl2, (D) hexarhomboid S2 in CD3CN (the asterisk represents the methanol signal peak), and (E) L3 in CD2Cl2.

Pd0 was used as the catalyst (Scheme 1). As might be expected, the coordination dimer metallomacrocyclic rhomboid S1 was quantitatively formed, which was fully characterized by 1D and 2D NMR and electrospray ionization mass spectrometry (ESIMS; Figure 2B and the Supporting Information, SI). To gain an additional understanding of the self-complementary rhombic geometry, two novel MOLs L2 and L3 were redesigned and synthesized (Scheme 1B). Both of these two were similar to the one above L1 but contain four parallel free

terpyridines, which were composed of two homologous openorientation parallelograms. Similarly, they were synthesized in multiple steps starting from simple organic compounds, and the final steps were conducted by palladium-mediated coupling reactions of tetrabromo-substituted ruthenium(II) compounds C2 and C3 and 4′-(4-boronophenyl)terpyridine in good yield (Schemes S2 and S3). It is worth mentioning that the “reaction on complex” here seems difficult for complex L3, which needs a tough purification process. B

DOI: 10.1021/acs.inorgchem.9b00867 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry The 1H NMR spectrum of L2 (Figure 2C) displays four singlets at 9.03, 8.83, 8.78, and 8.73 ppm with a 1:2:1:2 integration ratio attributed to the four kinds of tpy-H3′,5′ protons, and the nonaromatic region exhibits two singlets at 4.10 and 3.80 ppm with a 1:2 ratio corresponding to the protons of −OCH3. Sharp and distinguished signal peaks are also clearly observed in the 1H NMR spectrum of L3 (Figure 2E), which displays four singlets at 9.10, 9.03, 8.86, and 8.80 ppm with a 1:1:1:1 integration ratio attributed to the four kinds of tpy-H3′,5′ protons and three −OCH3 proton singlets with a 2:1:1 ratio at 4.03, 3.20, and 3.14 ppm, respectively. In addition, the spectral assignments of all ligands were confirmed by 2D COSY and NOESY experiments (see the SI). After ligands L2 and L3 were mixed with Zn2+ ions in a ratio of 1:1:4, the multiple components were accurately assembled into a single molecular hexarhomboid polygon S2 in quantitative yield. In a comparison of the 1H NMR spectra of substrates L2 and L3 with that of hexarhomboid S2 (Figure 2D), all tpy-H6,6′′ protons from uncomplexed tpy units were significantly shifted upfield after coordination with ZnII ions due to the electron shielding effects. In particular, all kinds of methoxy groups were well differentiated at 4.21, 4.09, 3.93, 3.38, and 3.28 ppm with a ratio of 1:2:2:1:1 in the nonaromatic region, which were consistent with the expected architectures. Other assignments of all protons were confirmed by 2D COSY and NOESY experiments (Figures S7 and S8). Convincing proof of the hexarhomboid architecture S2 was gained based on high-resolution ESI-MS and traveling-wave ion-mobility mass spectrometry (TWIM-MS). As shown in Figure 3A, the ESI-MS spectra display a series of signal peaks

of hexarhomboid S2, a reaction with ligands L2 and L3 and Zn2+ in a 1:1:2 ratio was conducted. The product was characterized by ESI-MS, showing the presence of a major intermediate Zn2L2L3 with four uncoordinated terpyridines (Figure S58). The narrow drifting time band of S2 in the TWIM-MS spectra at charge states from 25+ to 14+ indicated that no isomers or conformers existed (Figure 2B). Furthermore, considering that the structural characteristic of a rhomboid is relatively stable, the stability of the hexarhomboid architecture was investigated by ESI-MS collision-induced dissociation experiments (Figure S59). The formation of S2 was also evidenced by 2D diffusionordered NMR spectroscopy (DOSY). The 2D DOSY spectrum displayed a narrow band with a diffusion coefficient of 1.20 × 10−10 m2 s−1, suggesting that a single product was obtained (Figure S10). According to the Stokes−Einstein Formula, the hydrodynamic radius of S2 is 4.84 nm, which is in accordance with the molecular modeling simulated data. Transmission electron microscopy (TEM) was further employed to confirm the shape and size of the multirhomboid structure. The product was dissolved in acetonitrile at a concentration of ∼10−6 M and then dripped onto the carboncoated grids (copper, 400 mesh). Under the 20 nm scale, the shape of S2 can be roughly observed. The molecules are evenly distributed on the carbon film, and the hexarhomboid architecture was measured to have a size of about 9.1 ± 0.2 nm, which is closed to the energy minimization structure (Figure 4).

Figure 4. (A) TEM image and (B) energy-minimized structure of S2.

In summary, a C3-symmetric hexarhomboid architecture, S2, has been designed and synthesized from two ruthenium(II)− organic building blocks. Both of complementary MOLs L2 and L3 were obtained by a stepwise procedure. This is an exiguous example of two types of terpyridine-based MOLs that were successfully spliced in quantitative yield. 1D and 2D NMR, high-resolution ESI-MS, 2D TWIM-MS, and TEM measurements unambiguously supported formation of the desired product. In addition, this multirhomboid structure keeps good stability under a voltage of 30 V in the ESI-MS collisioninduced dissociation experiments. More investigations on the metallomacrocyclic properties are ongoing. The strategy using complementary building blocks to construct uncommon metallosupramolecules is expected to provide a facile avenue for future research.

Figure 3. (A) ESI-MS spectra (inset: calculated and experimental isotopic patterns for 19+ moieties) and (B) 2D TWIM-MS plots (m/ z vs drift time) for the hexarhomboid structure S2. The charge states are marked.

with normal distribution for charge states from 22+ to 12+ due to a loss of the corresponding PF6− anions, and their values were consistent with the theoretical ones derived from the assembled composition of S2 with a molecular weight of ca. 22 621 Da. The available experimental isotopic pattern agrees well with the corresponding simulated isotope pattern of the proposed structure. In order to gain insight into the formation

■

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.inorgchem.9b00867. C

DOI: 10.1021/acs.inorgchem.9b00867 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry

(13) Danon, J. J.; Krüger, A.; Leigh, D. A.; Lemonnier, J. F.; Stephens, A. J.; Vitoricayrezabal, I. J.; Woltering, S. L. Braiding a molecular knot with eight crossings. Science 2017, 355, 159−162. (14) Howlader, P.; Das, P.; Zangrando, E.; Mukherjee, P. S. UreaFunctionalized Self-Assembled Molecular Prism for Heterogeneous Catalysis in Water. J. Am. Chem. Soc. 2016, 138, 1668−1676. (15) Hofmeier, H.; Schubert, U. S. Recent developments in the supramolecular chemistry of terpyridine-metal complexes. Chem. Soc. Rev. 2004, 33, 373−399. (16) Pal, A. K.; Hanan, G. S. Design, synthesis and excited-state properties of mononuclear Ru(II) complexes of tridentate heterocyclic ligands. Chem. Soc. Rev. 2014, 43, 6184−6197. (17) Chakraborty, S.; Newkome, G. R. Terpyridine-based metallosupramolecular constructs: tailored monomers to precise 2D-motifs and 3D-metallocages. Chem. Soc. Rev. 2018, 47, 3991−4016. (18) Xie, T. Z.; Wu, X.; Endres, K. J.; Guo, Z.; Lu, X.; Li, J.; Manandhar, E.; Ludlow, J. M., 3rd; Moorefield, C. N.; Saunders, M. J.; Wesdemiotis, C.; Newkome, G. R. Supercharged, Precise, Megametallodendrimers via a Single-Step, Quantitative, Assembly Process. J. Am. Chem. Soc. 2017, 139, 15652−15655. (19) Newkome, G. R.; Moorefield, C. N. From 1 3 dendritic designs to fractal supramacromolecular constructs: understanding the pathway to the Sierpinski gasket. Chem. Soc. Rev. 2015, 44, 3954−3967. (20) Zhang, Z.; Wang, H.; Wang, X.; Li, Y.; Song, B.; Bolarinwa, O.; Reese, R. A.; Zhang, T.; Wang, X. Q.; Cai, J.; Xu, B.; Wang, M.; Liu, C.; Yang, H. B.; Li, X. Supersnowflakes: Stepwise Self-Assembly and Dynamic Exchange of Rhombus Star-Shaped Supramolecules. J. Am. Chem. Soc. 2017, 139, 8174−8185. (21) Wang, M.; Wang, C.; Hao, X. Q.; Liu, J.; Li, X.; Xu, C.; Lopez, A.; Sun, L.; Song, M. P.; Yang, H. B.; Li, X. Hexagon wreaths: selfassembly of discrete supramolecular fractal architectures using multitopic terpyridine ligands. J. Am. Chem. Soc. 2014, 136, 6664− 6671. (22) Wang, S. Y.; Fu, J. H.; Liang, Y. P.; He, Y. J.; Chen, Y. S.; Chan, Y. T. Metallo-Supramolecular Self-Assembly of a Multicomponent Ditrigon Based on Complementary Terpyridine Ligand Pairing. J. Am. Chem. Soc. 2016, 138, 3651−3654. (23) Fu, J. H.; Lee, Y. H.; He, Y. J.; Chan, Y. T. Facile Self-Assembly of Metallo-Supramolecular Ring-in-Ring and Spiderweb Structures Using Multivalent Terpyridine Ligands. Angew. Chem., Int. Ed. 2015, 54, 6231−6235. (24) Jiang, Z.; Li, Y.; Wang, M.; Song, B.; Wang, K.; Sun, M.; Liu, D.; Li, X.; Yuan, J.; Chen, M.; Guo, Y.; Yang, X.; Zhang, T.; Moorefield, C. N.; Newkome, G. R.; Xu, B.; Li, X.; Wang, P. Selfassembly of a supramolecular hexagram and a supramolecular pentagram. Nat. Commun. 2017, 8, 15476−15484. (25) Liu, D.; Chen, M.; Li, Y.; Shen, Y.; Huang, J.; Yang, X.; Jiang, Z.; Li, X.; Newkome, G. R.; Wang, P. Vertical Assembly of Giant Double- and Triple-Decker Spoked Wheel Supramolecular Structures. Angew. Chem., Int. Ed. 2018, 57, 14116−14120. (26) Carbonell, E.; Bivona, L. A.; Fusaro, L.; Aprile, C. Silsesquioxane-Terpyridine Nano Building Blocks for the Design of Three-Dimensional Polymeric Networks. Inorg. Chem. 2017, 56, 6393−6403. (27) Preston, D.; Tucker, R. A.; Garden, A. L.; Crowley, J. D. Heterometallic [MnPtn(L)2n](x+) Macrocycles from Dichloromethane-Derived Bis-2-pyridyl-1,2,3-triazole Ligands. Inorg. Chem. 2016, 55, 8928−8934. (28) Newkome, G. R.; Wang, P.; Moorefield, C. N.; Cho, T. J.; Mohapatra, P. P.; Li, S.; Hwang, S. H.; Lukoyanova, O.; Echegoyen, L.; Palagallo, J. A.; Iancu, V.; Hla, S. W. Nanoassembly of a fractal polymer: a molecular ″Sierpinski hexagonal gasket″. Science 2006, 312, 1782−1785. (29) Li, Y.; Jiang, Z.; Wang, M.; Yuan, J.; Liu, D.; Yang, X.; Chen, M.; Yan, J.; Li, X.; Wang, P. Giant, Hollow 2D Metalloarchitecture: Stepwise Self-Assembly of a Hexagonal Supramolecular Nut. J. Am. Chem. Soc. 2016, 138, 10041−10046.

Detailed synthetic protocols and characterization data for ligands and complexes, Schemes S1−S3, and Figures S1−S59 (PDF)

■

AUTHOR INFORMATION

Corresponding Authors

*E-mail: [email protected] (M.C.). *E-mail: [email protected] (P.W.). ORCID

Jun Yan: 0000-0002-6158-0614 Yi-Tsu Chan: 0000-0001-9658-2188 Pingshan Wang: 0000-0002-1988-7604 Author Contributions ‡

J.W. and X.X. contributed equally to this work.

Notes

The authors declare no competing financial interest.

■

ACKNOWLEDGMENTS Y.-T.C. acknowledges support from the Ministry of Science and Technology of Taiwan (Grant MOST106-2628-M-002007-MY3). The authors acknowledge the NMR measurements from The Modern Analysis and Testing Center of CSU.

■

REFERENCES

(1) Lehn, J. M. Toward complex matter: supramolecular chemistry and self-organization. Proc. Natl. Acad. Sci. U. S. A. 2002, 99, 4763− 4768. (2) Chakrabarty, R.; Mukherjee, P. S.; Stang, P. J. Supramolecular coordination: self-assembly of finite two- and three-dimensional ensembles. Chem. Rev. 2011, 111, 6810−6918. (3) Smulders, M. M.; Riddell, I. A.; Browne, C.; Nitschke, J. R. Building on architectural principles for three-dimensional metallosupramolecular construction. Chem. Soc. Rev. 2013, 42, 1728−1754. (4) Marcos, V.; Stephens, A. J.; Jaramillogarcia, J.; Nussbaumer, A. L.; Woltering, S. L.; Valero, A.; Lemonnier, J. F.; Vitoricayrezabal, I. J.; Leigh, D. A. Allosteric initiation and regulation of catalysis with a molecular knot. Science 2016, 352, 1555−1559. (5) Yam, V. W.; Au, V. K.; Leung, S. Y. Light-Emitting SelfAssembled Materials Based on d(8) and d(10) Transition Metal Complexes. Chem. Rev. 2015, 115, 7589−7728. (6) Ward, M. D.; Raithby, P. R. Functional behaviour from controlled self-assembly: challenges and prospects. Chem. Soc. Rev. 2013, 42, 1619−1636. (7) Baxter, P.; Lehn, J. M.; Decian, A.; Fischer, J. Multicomponent Self-Assembly: Spontaneous Formation of a Cylindrical Complex from Five Ligands and Six Metal Ions. Angew. Chem., Int. Ed. Engl. 1993, 32, 69−72. (8) Collin, J. P.; Dietrich-Buchecker, C.; Gaviña, P.; JimenezMolero, M. C.; Sauvage, J. P. Shuttles and muscles: linear molecular machines based on transition metals. Acc. Chem. Res. 2001, 34, 477− 487. (9) Stang, P. J.; Olenyuk, B. Self-Assembly, Symmetry, and Molecular Architecture: Coordination as the Motif in the Rational Design of Supramolecular Metallacyclic Polygons and Polyhedra. Acc. Chem. Res. 1997, 30, 502−518. (10) Fujita, M. Metal-directed self-assembly of two- and threedimensional synthetic receptors. Chem. Soc. Rev. 1998, 27, 417−425. (11) Cook, T. R.; Stang, P. J. Recent Developments in the Preparation and Chemistry of Metallacycles and Metallacages via Coordination. Chem. Rev. 2015, 115, 7001−7045. (12) Wood, C. S.; Ronson, T. K.; Belenguer, A. M.; Holstein, J. J.; Nitschke, J. R. Two-stage directed self-assembly of a cyclic [3]catenane. Nat. Chem. 2015, 7, 354−358. D

DOI: 10.1021/acs.inorgchem.9b00867 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry (30) Schmittel, M.; He, B.; Mal, P. Supramolecular multicomponent self-assembly of shape-adaptive nanoprisms: wrapping up C(60) with three porphyrin units. Org. Lett. 2008, 10, 2513−2516. (31) Chen, M.; Wang, J.; Liu, D.; Jiang, Z.; Liu, Q.; Wu, T.; Liu, H.; Yu, W.; Yan, J.; Wang, P. Highly Stable Spherical Metallo-Capsule from a Branched Hexapodal Terpyridine and Its Self-Assembled Berry-type Nanostructure. J. Am. Chem. Soc. 2018, 140, 2555−2561. (32) Fujita, M.; Aoyagi, M.; Ogura, K. Macrocyclic dinuclear complexes self-assembled from (en)Pd(NO3)2 and pyridine-based bridging ligands. Inorg. Chim. Acta 1996, 246, 53−57. (33) Yang, H.; Das, N.; Huang, F.; Hawkridge, A. M.; Díaz, D. D.; Arif, A. M.; Finn, M. G.; Muddiman, D. C.; Stang, P. J. Incorporation of 2,6-di(4,4’-dipyridyl)-9-thiabicyclo[3.3.1]nonane into discrete 2D supramolecules via coordination-driven self-assembly. J. Org. Chem. 2006, 71, 6644−6647. (34) Northrop, B. H.; Zheng, Y. R.; Chi, K. W.; Stang, P. J. Selforganization in coordination-driven self-assembly. Acc. Chem. Res. 2009, 42, 1554−1563. (35) Lu, X.; Li, X.; Wang, J. L.; Moorefield, C. N.; Wesdemiotis, C.; Newkome, G. R. From supramolecular triangle to heteroleptic rhombus: a simple bridge can make a difference. Chem. Commun. 2012, 48, 9873−9875. (36) Wang, S. Y.; Huang, J. Y.; Liang, Y. P.; He, Y. J.; Chen, Y. S.; Zhan, Y. Y.; Hiraoka, S.; Liu, Y. H.; Peng, S. M.; Chan, Y. T. Multicomponent Self-Assembly of Metallo-Supramolecular Macrocycles and Cages through Dynamic Heteroleptic Terpyridine Complexation. Chem. - Eur. J. 2018, 24, 9274−9284. (37) Lee, J.; Ghosh, K.; Stang, P. J. Stoichiometric control of multiple different tectons in coordination-driven self-assembly: preparation of fused metallacyclic polygons. J. Am. Chem. Soc. 2009, 131, 12028−12029. (38) Acharyya, K.; Mukherjee, P. S. Shape and size directed selfselection in organic cage formation. Chem. Commun. 2015, 51, 4241− 4244. (39) Bloch, W. M.; Abe, Y.; Holstein, J. J.; Wandtke, C. M.; Dittrich, B.; Clever, G. H. Geometric Complementarity in Assembly and Guest Recognition of a Bent Heteroleptic cis-[Pd2L(A)2L(B)2] Coordination Cage. J. Am. Chem. Soc. 2016, 138, 13750−13755. (40) Saha, M. L.; Mittal, N.; Bats, J. W.; Schmittel, M. A sixcomponent metallosupramolecular pentagon via self-sorting. Chem. Commun. 2014, 50, 12189−12192.

E

DOI: 10.1021/acs.inorgchem.9b00867 Inorg. Chem. XXXX, XXX, XXX−XXX