Abstract
We demonstrate near-infrared (NIR) absorptive and emissive poly(p-phenylene vinylene) (PPV)-type π-conjugated polymers based on hypervalent tin-fused azobenzene (TAz) complexes. Taking advantage of the inherent narrow-energy gap of TAz complexes originating from the three-center four-electron (3c-4e) bond and nitrogen–tin (N–Sn) coordination, the synthesized polymers, TAz-PPVs, showed absorption, and emission in wavelength regions of >750 and 810 nm in diluted solution, respectively. From the experimental and theoretical investigations, the elevation of the highest occupied molecular orbital (HOMO) and the reduction of the lowest unoccupied molecular orbital (LUMO) were simultaneously shown to be caused by the extension of π-conjugation. The effective conjugation length was calculated to be n > 10 (n: degree of polymerization), and the value was comparable to conventional PPV systems. Through this research, we revealed that π-conjugated systems including hypervalent bonds were able to expand π-conjugation. According to the concept of “element blocks”, the development of heteroatom-containing narrow-energy-gap monomers should be a novel approach for the construction of new NIR-absorptive and emissive bland materials.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Roggo Y, Chalus P, Maurer L, Lema-Martinez C, Edmond A, Jent N. A review of near infrared spectroscopy and chemometrics in pharmaceutical technologies. J Pharm Biomed Anal. 2007;44:683–700.
Bünzli JCG, Eliseeva SV. Lanthanide NIR luminescence for telecommunications, bioanalyses and solar energy conversion. J Rare Earths. 2010;28:824–42.
Cai Y, Wei Z, Song C, Tang C, Han W, Dong X. Optical nano-agents in the second near-infrared window for biomedical applications. Chem Soc Rev. 2019;48:22–37.
Ding F, Zhan Y, Lu X, Sun Y. Recent advances in near-infrared II fluorophores for multifunctional biomedical imaging. Chem Sci. 2018;9:4370–80.
Ning Y, Zhu M, Zhang JL. Near-infrared (NIR) lanthanide molecular probes for bioimaging and biosensing. Coord Chem Rev. 2019;399:213028.
Li Q, Guo Y, Liu Y. Exploration of near-infrared organic photodetectors. Chem Mater. 2019;31:6359–79.
Zou D, Zhang J, Cui Y, Qian G. Near-infrared-emissive metal–organic frameworks. Dalton Trans. 2019;48:6669–75.
Huang X, Zhang W, Guan G, Song G, Zou R, Hu J. Design and functionalization of the NIR-responsive photothermal semiconductor nanomaterials for cancer theranostics. Acc Chem Res. 2017;50:2529–38.
Xiang H, Cheng J, Ma X, Zhou X, Chruma JJ. Near-infrared phosphorescence: materials and applications. Chem Soc Rev. 2013;42:6128–85.
Yuan L, Lin W, Zheng K, He L, Huang W. Far-red to near infrared analyte-responsive fluorescent probes based on organic fluorophore platforms for fluorescence imaging. Chem Soc Rev. 2013;42:622–61.
Zampetti A, Minotto A, Cacialli F. Near-infrared (NIR) organic light-emitting diodes (OLEDs): challenges and opportunities. Adv Funct Mater. 2019;29:1807623.
Lu H, Mack J, Yang Y, Shen Z. Structural modification strategies for the rational design of red/NIR region BODIPYs. Chem Soc Rev. 2014;43:4778–823.
Dou L, Liu Y, Hong Z, Li G, Yang Y. Low-bandgap near-IR conjugated polymers/molecules for organic electronics. Chem Rev. 2015;115:12633–65.
Wang Y, Zhang H, Wang Z, Feng L. Photothermal conjugated polymers and their biological applications in imaging and therapy. ACS Appl Polym Mater. 2020;2:4222–40.
Jiang Y, Pu K. Multimodal biophotonics of semiconducting polymer nanoparticles. Acc Chem Res. 2018;51:1840–9.
Kage Y, Kang S, Mori S, Mamada M, Adachi C, Kim D, et al. An electron-accepting aza-BODIPY-based donor–acceptor–donor architecture for bright NIR emission. Chem Eur J. 2021;27:5259–67.
Loaeza L, Corona-Sánchez R, Castro G, Romero-Ávila M, Santillan R, Maraval V, et al. Synthesis and optical properties of 1-ethyl-indol-3-yl-substituted aza-BODIPY dyes at the 1,7-positions. Tetrahedron. 2021;83:131983.
Kawano Y, Ito Y, Ito S, Tanaka K, Chujo Y. π-conjugated copolymers composed of boron formazanate and their application for a wavelength converter to near-infrared light. Macromolecules. 2021;54:1934–42.
Sahu K, Mondal S, Mobin SM, Kar S. Photocatalytic C–H thiocyanation of corroles: development of near-infrared (NIR)-emissive dyes. J Org Chem. 2021;86:3324–33.
Zhang Q, Yu P, Fan Y, Sun C, He H, Liu X, et al. Bright and stable NIR-II J-aggregated AIE dibodipy-based fluorescent probe for dynamic in vivo bioimaging. Angew Chem Int Ed. 2021;60:3967–73.
Grimme J, Kreyenschmidt M, Uckert F, Müllen K, Scherf U. On the conjugation length in poly(para-phenylene)-type polymers. Adv Mater. 1995;7:292–5.
Rissler J. Effective conjugation length of π-conjugated systems. Chem Phys Lett. 2004;395:92–6.
Hoffmann ST, Bässler H, Köhler A. What determines inhomogeneous broadening of electronic transitions in conjugated polymers? J Phys Chem B. 2010;114:17037–48.
Tanaka K, Chujo Y. New idea for narrowing an energy gap by selective perturbation of one frontier molecular orbital. Chem Lett. 2021;50:269–79.
Watanabe H, Tanaka K, Chujo Y. Independently tuned frontier orbital energy levels of 1,3,4,6,9b-pentaazaphenalene derivatives by the conjugation effect. J Org Chem. 2019;84:2768–78.
Watanabe H, Ochi J, Tanaka K Chujo Y. Tuning the NIR absorption properties of 1,3,4,6,9b-pentaazaphenalene derivatives through the spatially separated frontier molecular orbitals. Eur J Org Chem. 2020:777–83.
Watanabe H, Kawano Y, Tanaka K, Chujo Y. Enhancing light-absorption and luminescent properties of non-emissive 1,3,4,6,9b-pentaazaphenalene through perturbation of forbidden electronic transition by boron complexation. Asian J Org Chem. 2020;9:259–66.
Chujo Y, Tanaka K. New polymeric materials based on element-blocks. Bull Chem Soc Jpn. 2015;88:633–43.
Gon M, Tanaka K, Chujo Y. Recent progress in the development of advanced element-block materials. Polym J. 2018;50:109–26.
Tanaka K, Chujo Y. Modulation of the solid-state luminescent properties of conjugated polymers by changing the connecting points of flexible boron element blocks. Polym J. 2020;52:555–66.
Gon M, Saotome S, Tanaka K, Chujo Y. Paintable hybrids with thermally stable dual emission composed of tetraphenylethene-integrated POSS and MEH-PPV for heat-resistant white-light luminophores. ACS Appl Mater Interfaces. 2021;13:12483–90.
Gon M, Sato K, Kato K, Tanaka K, Chujo Y. Preparation of bright-emissive hybrid materials based on light-harvesting POSS having radially integrated luminophores and commercial π-conjugated polymers. Mater Chem Front. 2019;3:314–20.
Gon M, Kato K, Tanaka K, Chujo Y. Elastic and mechanofluorochromic hybrid films with POSS-capped polyurethane and polyfluorene. Mater Chem Front. 2019;3:1174–80.
Ochi J, Tanaka K, Chujo Y. Recent progress in the development of solid-state luminescent o-Carboranes with stimuli responsivity. Angew Chem Int Ed. 2020;59:9841–55.
Ochi J, Tanaka K, Chujo Y. Experimental proof for emission annihilation through bond elongation at the carbon–carbon bond in o-carborane with fused biphenyl-substituted compounds. Dalton Trans. 2021;50:1025–33.
Morisue M, Kusukawa T, Watase S. Dipyrrin complexes of borasiloxane silanols with adaptive hydrogen-bonded conformations in the crystal and in solution states. Eur J Inorg Chem. 2020:1885–93.
Zhao R, Liu J, Wang L. Polymer acceptors containing B←N units for organic photovoltaics. Acc Chem Res. 2020;53:1557–67.
Nishiyama H, Zheng F, Inagi S, Fueno H, Tanaka K, Tomita I. Tellurophene-containing π-conjugated polymers with unique heteroatom–heteroatom interactions by post-element-transformation of an organotitanium polymer. Polym Chem. 2020;11:4693–8.
Imoto H, Naka K. The dawn of functional organoarsenic chemistry. Chem Eur J. 2019;25:1883–94.
Tanabe M, Hagio T, Osakada K, Nakamura M, Hayashi Y, Ohshita J. Synthesis of 4,4-dihydrodithienosilole and its unexpected cyclodimerization catalyzed by Ni and Pt complexes. Organometallics. 2017;36:1974–80.
Gon M, Tanaka K, Chujo Y. Discovery of functional luminescence properties based on flexible and bendable boron-fused azomethine/azobenzene complexes with O,N,O-type tridentate ligands. Chem Rec. https://doi.org/10.1002/tcr.202000156. In press.
Ohtani S, Gon M, Tanaka K, Chujo Y. Construction of the luminescent donor–acceptor conjugated systems based on boron-fused azomethine acceptor. Macromolecules. 2019;52:3387–93.
Gon M, Wakabayashi J, Nakamura M, Tanaka K, Chujo Y. Controlling energy gaps of π-conjugated polymers by multi-fluorinated boron-fused azobenzene acceptors for highly efficient near-infrared emission. Chem Asian J. 2021;16:696–703.
Gon M, Wakabayashi J, Nakamura M, Tanaka K, Chujo Y. Preparation of near-infrared emissive π-conjugated polymer films based on boron-fused azobenzene complexes with perpendicularly protruded aryl substituents. Macromol. Rapid Commun. 2021;42:2000566.
Gon M, Tanaka K, Chujo Y. A highly efficient near-infrared-emissive copolymer with a N=N double-bond π-conjugated system based on a fused azobenzene-boron complex. Angew Chem Int Ed. 2018;57:6546–51.
Wakabayashi J, Gon M, Tanaka K, Chujo Y. Near-infrared absorptive and emissive Poly(p-phenylene vinylene) derivative containing azobenzene–boron complexes. Macromolecules. 2020;53:4524–32.
Gon M, Wakabayashi J, Tanaka K, Chujo Y. Unique substitution effect at 5,5′-positions of fused azobenzene–boron complexes with a N=N π-conjugated system. Chem Asian J. 2019;14:1837–43.
Ohtani S, Gon M, Tanaka K, Chujo Y. A flexible, fused, azomethine–boron complex: thermochromic luminescence and thermosalient behavior in structural transitions between crystalline polymorphs. Chem Eur J. 2017;23:11827–33.
Ohtani S, Takeda Y, Gon M, Tanaka K, Chujo Y. Facile strategy for obtaining luminescent polymorphs based on the chirality of a boron-fused azomethine complex. Chem Commun. 2020;56:15305–8.
Ohtani S, Nakamura M, Gon M, Tanaka K, Chujo Y. Synthesis of fully-fused bisboron azomethine complexes and their conjugated polymers with solid-state near-infrared emission. Chem Commun. 2020;56:6575–8.
Ohtani S, Gon M, Tanaka K, Chujo Y. The design strategy for an aggregation- and crystallization-induced emission-active molecule based on the introduction of skeletal distortion by boron complexation with a tridentate ligand. Crystals. 2020;10:615.
Liu CL, Tsai FC, Chang CC, Hsieh KH, Lin JL, Chen WC. Theoretical analysis on the geometries and electronic structures of coplanar conjugated poly(azomethine)s. Polymer. 2005;46:4950–7.
Tsuji H, Nakamura E. Carbon-bridged oligo(phenylene vinylene)s: a de novo designed, flat, rigid, and stable π-conjugated system. Acc Chem Res. 2019;52:2939–49.
Meier H, Stalmach U, Kolshorn H. Effective conjugation length and UV/vis spectra of oligomers. Acta Polym. 1997;48:379–84.
Panda AN, Plasser F, Aquino AJA, Burghardt I, Lischka H. Electronically excited states in poly(p-phenylenevinylene): vertical excitations and torsional potentials from high-level ab initio calculations. J Phys Chem A. 2013;117:2181–9.
Cardozo TM, Aquino AJA, Barbatti M, Borges I, Lischka H. Absorption and fluorescence spectra of poly(p-phenylenevinylene) (PPV) oligomers: an ab initio simulation. J Phys Chem A. 2015;119:1787–95.
Kim DY, Grey JK, Barbara PF. A detailed single molecule spectroscopy study of the vibronic states and energy transfer pathways of the conjugated polymer MEH-PPV. Synth Met. 2006;156:336–45.
Padmanaban G, Ramakrishnan S. Fluorescence spectroscopic studies of solvent- and temperature-induced conformational transition in segmented poly[2-methoxy-5-(2′-ethylhexyl)oxy-1,4-phenylenevinylene] (MEHPPV). J Phys Chem B. 2004;108:14933–41.
Amrutha SR, Jayakannan M. Probing the π-stacking induced molecular aggregation in π-conjugated polymers, oligomers, and their blends of p-phenylenevinylenes. J Phys Chem B. 2008;112:1119–29.
Blayney AJ, Perepichka IF, Wudl F, Perepichka DF. Advances and challenges in the synthesis of poly(p-phenylene vinylene)-based polymers. Isr J Chem. 2014;54:674–88.
Greenham NC, Moratti SC, Bradley DDC, Friend RH, Holmes AB. Efficient light-emitting diodes based on polymers with high electron affinities. Nature. 1993;365:628–30.
Lei T, Dou JH, Cao XY, Wang JY, Pei J. Electron-deficient poly(p-phenylene vinylene) provides electron mobility over 1 cm2 V–1 s–1 under ambient conditions. J Am Chem Soc. 2013;135:12168–71.
Savagatrup S, Printz AD, O’Connor TF, Zaretski AV, Lipomi DJ. Molecularly stretchable electronics. Chem Mater. 2014;26:3028–41.
Gon M, Tanaka K, Chujo Y. Vapochromic luminescent π-conjugated systems with reversible coordination-number control of hypervalent tin(IV)-fused azobenzene complexes. Chem. Eur J. 2021;27:7561–71.
Bessler KE, dos Santos JA, Deflon VM, de Souza Lemos S, Niquet E. Organotin dyes: synthesis and structural characterization of dibutyltin and dimethyltin complexes with 2, 2′-dihydroxyazobenzene. Z Anorg Allg Chem. 2004;630:742–5.
Kosugi M, Sasazawa K, Shimizu Y, Migita T. REACTIONS OF ALLYLTIN COMPOUNDS III. ALLYLATION OF AROMATIC HALIDES WITH ALLYLTRIBUTYLTIN IN THE PRESENCE OF TETRAKIS(TRIPHENYLPHOSPHINE)PALLADIUM(O). Chem Lett. 1977;6:301–2.
Milstein D, Stille JK. A general, selective, and facile method for ketone synthesis from acid chlorides and organotin compounds catalyzed by palladium. J Am Chem Soc. 1978;100:3636–8.
Englman R, Jortner J. The energy gap law for radiationless transitions in large molecules. Mol Phys. 1970;18:145–64.
Chynwat V, Frank HA. The application of the energy gap law to the S1 energies and dynamics of carotenoids. Chem Phys. 1995;194:237–44.
Biczók L, Bérces T, Inoue H. Effects of Molecular structure and hydrogen bonding on the radiationless deactivation of singlet excited fluorenone derivatives. J Phys Chem A. 1999;103:3837–42.
Yeo H, Tanaka K, Chujo Y. Tunable optical property between pure red luminescence and dual emission depended on the length of light-harvesting antennae in the dyads containing the cardo structure of BODIPY and oligofluorene. Macromolecules. 2016;49:8899–904.
Pommerehne J, Vestweber H, Guss W, Mahrt RF, Bässler H, Porsch M, et al. Efficient two layer leds on a polymer blend basis. Adv Mater. 1995;7:551–4.
Cardona CM, Li W, Kaifer AE, Stockdale D, Bazan GC. Electrochemical considerations for determining absolute frontier orbital energy levels of conjugated polymers for solar cell applications. Adv Mater. 2011;23:2367–71.
Meyers F, Heeger AJ, Brédas JL. Fine tuning of the band gap in conjugated polymers via control of block copolymer sequences. J Chem Phys. 1992;97:2750–8.
Ma J, Li S, Jiang Y. A time-dependent DFT study on band gaps and effective conjugation lengths of polyacetylene, polyphenylene, polypentafulvene, polycyclopentadiene, polypyrrole, polyfuran, polysilole, polyphosphole, and polythiophene. Macromolecules. 2002;35:1109–15.
Acknowledgements
This work was partially supported by the Research Institute for Production Development, Japan (for MG) and a Grant-in-Aid for Early-Career Scientists (for MG) (JSPS KAKENHI Grant numbers 20K15334) for Scientific Research (B) (for KT), (JP17H03067), for Scientific Research on Innovative Areas “New Polymeric Materials Based on Element Blocks (No. 2401)” (JP24102013) and for Challenging Research (Pioneering) (JP18H05356).
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no conflict of interest.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Rights and permissions
About this article
Cite this article
Gon, M., Tanimura, K., Yaegashi, M. et al. PPV-type π-conjugated polymers based on hypervalent tin(IV)-fused azobenzene complexes showing near-infrared absorption and emission. Polym J 53, 1241–1249 (2021). https://doi.org/10.1038/s41428-021-00506-x
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/s41428-021-00506-x
This article is cited by
-
New strategy for lowering the energy levels of one frontier molecular orbital in conjugated molecules and polymers based on Aza-substitution at the isolated HOMO or LUMO
Polymer Journal (2024)
-
π-Conjugated polymers based on flexible heteroatom-containing complexes for precise control of optical functions
Polymer Journal (2023)
-
Frustrated element-blocks: A new platform for constructing unique stimuli-responsive luminescent materials
Polymer Journal (2023)