Three symmetrically and three unsymmetrically substituted cibalackrot (7,14-diphenyldiindolo[3,2,1-de:3',2',1'-ij][1,5]naphthyridine-6,13-dione, 1) dyes carrying two derivatized phenyl rings have been synthesized as candidates for molecular electronics and especially for singlet fission, a process of interest for solar energy conversion. Solution measurements provided singlet and triplet excitation energies and fluorescence yields and lifetimes; conformational properties were analyzed computationally. The molecular properties are close to ideal for singlet fission. However, crystal structures, obtained by single-crystal X-ray diffraction (XRD), are rather similar to those of the polymorphs of solid 1, in which the formation of a charge-separated state followed by intersystem crossing, complemented with excimer formation, outcompetes singlet fission. Results of calculations by the approximate SIMPLE method suggest which ones among the solid derivatives are the best candidates for singlet fission, but it appears difficult to change the crystal packing in a desirable direction. We also describe the preparation of three specifically deuteriated versions of 1, expected to help sort out the mechanism of fast intersystem crossing in its charge-separated state.

Advanced Light Source Lawrence Berkeley National Laboratory Berkeley California 94720 1460 United States

Department of Chemistry University of Colorado Boulder Colorado 80309 0215 United States

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Flemingovo nám 2 16610 Prague Czech Republic

J Heyrovsky Institute of Physical Chemistry Academy of Sciences of the Czech Republic Dolejškova 3 182 23 Prague 8 Czech Republic

University of Chemistry and Technology Technicka 5 16000 Prague 6 Czech Republic

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Engi G. Über neue Derivate des Indigos und anderer indigoider Farbstoffe. Z. Angew. Chem. 1914, 27, 144–148. 10.1002/ange.19140272003. DOI

Posner T.; Kempel W. Beiträge zur Kenntnis der Indigo-gruppe, IV.: Über einen neuen aus Indigo und Phenylessigester entstehenden Küpenfarbstoff. Ber. Dtsch. Chem. Ges. 1924, 57, 1311–1315. 10.1002/cber.19240570815. DOI

Fallon K. J.; Budden P.; Salvadori E.; Ganose A. M.; Savory C. N.; Eyre L.; Dowland S.; Ai Q.; Goodlett S.; Risko C.; Scanlon D. O.; Kay C. W. M.; Rao A.; Friend R. H.; Musser A. J.; Bronstein H. Exploiting Excited-State Aromaticity To Design Highly Stable Singlet Fission Materials. J. Am. Chem. Soc. 2019, 141, 13867–13876. 10.1021/jacs.9b06346. PubMed DOI

Fallon K. J.; Wijeyasinghe N.; Manley E. F.; Dimitrov S. D.; Yousaf S. A.; Ashraf R. S.; Duffy W.; Guilbert A. A. Y.; Freeman D. M. E.; Al-Hashimi M.; Nelson J.; Durrant J. R.; Chen L. X.; McCulloch I.; Marks T. J.; Clarke T. M.; Anthopoulos T. D.; Bronstein H. Indolo-naphthyridine-6,13-dione Thiophene Building Block for Conjugated Polymer Electronics: Molecular Origin of Ultrahigh n-Type Mobility. Chem. Mater. 2016, 28, 8366–8378. 10.1021/acs.chemmater.6b03671. DOI

Glowacki E. D.; Leonat L.; Voss G.; Bodea M.; Bozkurt Z.; Irimia-Vladu M.; Bauer S.; Sariciftci N. S.. Natural and Nature-inspired Semiconductors for Organic Electronics, SPIE Proceedings; SPIE, 2011.

Głowacki E. D.; Voss G.; Sariciftci N. S. 25th Anniversary Article: Progress in Chemistry and Applications of Functional Indigos for Organic Electronics. Adv. Mater. 2013, 25, 6783–6800. 10.1002/adma.201302652. PubMed DOI

Shukla A.; Wallwork N. R.; Li X.; Sobus J.; Mai V. T. N.; McGregor S. K. M.; Chen K.; Lepage R. J.; Krenske E. H.; Moore E. G.; Namdas E. B.; Lo S.-C. Deep-Red Lasing and Amplified Spontaneous Emission from Nature Inspired Bay-Annulated Indigo Derivatives. Adv. Opt. Mater. 2020, 8, 190135010.1002/adom.201901350. DOI

Ryerson J. L.; Zaykov A.; Suarez L. E. A.; Havenith R. W. A.; Stepp B. R.; Dron P. I.; Kaleta J.; Akdag A.; Teat S. J.; Magnera T. F.; Miller J. R.; Havlas Z.; Broer R.; Faraji S.; Michl J.; Johnson J. C. Structure and Photophysics of Indigoids for Singlet Fission: Cibalackrot. J. Chem. Phys. 2019, 151, 18490310.1063/1.5121863. PubMed DOI

Zeng W.; El Bakouri O.; Szczepanik D. W.; Bronstein H.; Ottosson H. Excited State Character of Cibalackrot-type Compounds Interpreted in Terms of Hückel-aromaticity: A Rationale for Singlet Fission Chromophore Design. Chem. Sci. 2021, 12, 6159–6171. 10.1039/D1SC00382H. PubMed DOI PMC

Weber F.; Mori H. Machine-learning Assisted Design Principle Search for Singlet Fission: An Example Study of Cibalackrot. npj Comput. Mater. 2022, 8, 17610.1038/s41524-022-00860-1. DOI

Zeng W.; Szczepanik D. W.; Bronstein H. Cibalackrot-type compounds: Stable singlet fission materials with aromatic ground state and excited state. J. Phys. Org. Chem. 2023, 36, e444110.1002/poc.4441. DOI

Stanger A. Singlet Fission and Aromaticity. J. Phys. Chem. A 2022, 126, 8049–8057. 10.1021/acs.jpca.2c04146. PubMed DOI

Smith M. B.; Michl J. Singlet Fission. Chem. Rev. 2010, 110, 6891–6936. 10.1021/cr1002613. PubMed DOI

Shockley W.; Queisser H. J. Detailed Balance Limit of Efficiency of p-n Junction Solar Cells. J. Appl. Phys. 1961, 32, 510–519. 10.1063/1.1736034. DOI

Hanna M. C.; Nozik A. J. Solar conversion efficiency of photovoltaic and photoelectrolysis cells with carrier multiplication absorbers. J. Appl. Phys. 2006, 100, 07451010.1063/1.2356795. DOI

Lee J.; Jadhav P.; Baldo M. A. High Efficiency Organic Multilayer Photodetectors Based on Singlet Exciton Fission. Appl. Phys. Lett. 2009, 95, 03330110.1063/1.3182787. DOI

Thompson N. J.; Congreve D. N.; Goldberg D.; Menon V. M.; Baldo M. A. Slow Light Enhanced Singlet Exciton Fission Solar Cells with a 126% Yield of Electrons Per Photon. Appl. Phys. Lett. 2013, 103, 26330210.1063/1.4858176. DOI

Tabachnyk M.; Ehrler B.; Bayliss S.; Friend R. H.; Greenham N. C. Triplet Diffusion in Singlet Exciton Fission Sensitized Pentacene Solar Cells. Appl. Phys. Lett. 2013, 103, 15330210.1063/1.4824420. DOI

Congreve D. N.; Lee J.; Thompson N. J.; Hontz E.; Yost S. R.; Reusswig P. D.; Bahlke M. E.; Reineke S.; Van Voorhis T.; Baldo M. A. External Quantum Efficiency Above 100% in a Singlet-Exciton-Fission-Based Organic Photovoltaic Cell. Science 2013, 340, 334–337. 10.1126/science.1232994. PubMed DOI

Thompson N. J.; Hontz E.; Congreve D. N.; Bahlke M. E.; Reineke S.; Van Voorhis T.; Baldo M. A. Nanostructured Singlet Fission Photovoltaics Subject to Triplet-Charge Annihilation. Adv. Mater. 2014, 26, 1366–1371. 10.1002/adma.201304588. PubMed DOI

Wu T. C.; Thompson N. J.; Congreve D. N.; Hontz E.; Yost S. R.; Van Voorhis T.; Baldo M. A. Singlet Fission Efficiency in Tetracene-Based Organic Solar Cells. Appl. Phys. Lett. 2014, 104, 19390110.1063/1.4876600. DOI

Yang L.; Tabachnyk M.; Bayliss S. L.; Böhm M. L.; Broch K.; Greenham N. C.; Friend R. H.; Ehrler B. Solution-Processable Singlet Fission Photovoltaic Devices. Nano Lett. 2015, 15, 354–358. 10.1021/nl503650a. PubMed DOI

Li J.; Chen Z.; Lei Y.; Xiong Z.; Zhang Y. Competition Between Singlet Exciton Fission, Radiation, and Dissociation Measured in Rubrene-Doped Amorphous Films. Synth. Met. 2015, 207, 13–17. 10.1016/j.synthmet.2015.05.026. DOI

de Melo J. S.; Rondão R.; Burrows H. D.; Melo M. J.; Navaratnam S.; Edge R.; Voss G. Photophysics of an Indigo Derivative (Keto and Leuco Structures) With Singular Properties. J. Phys. Chem. A 2006, 110, 13653–13661. 10.1021/jp057451w. PubMed DOI

Dinçalp H.; Saltan G. M.; Zafer C.; Kıymaz D. A. Bromo-substituted Cibalackrot Backbone, a Versatile Donor or Acceptor Main Core for Organic Optoelectronic Devices. J. Mol. Struct. 2018, 1173, 512–520. 10.1016/j.molstruc.2018.07.009. DOI

Turro N. J.; Lei X.-G.; Jockusch S.; Li W.; Liu Z.; Abrams L.; Ottaviani M. F. EPR Investigation of Persistent Radicals Produced from the Photolysis of Dibenzyl Ketones Adsorbed on ZSM-5 Zeolites. J. Org. Chem. 2002, 67, 2606–2618. 10.1021/jo011047l. PubMed DOI

Fountain K. R.; Heinze P.; Sherwood M.; Maddex D.; Gerhardt G. Acylation of Aromatic Substrates With Ketenes. An Example of Vinyl Oxocation Reactivity. Can. J. Chem. 1980, 58, 1198–1205. 10.1139/v80-187. DOI

Olah G. A.; Olah J. A.; Ohyama T. Friedel-Crafts Alkylation of Anisole and its Comparison with Toluene. Predominant Ortho-para Substitution Under Kinetic Conditions and the Effect of Thermodynamic Isomerizations. J. Am. Chem. Soc. 1984, 106, 5284–5290. 10.1021/ja00330a042. DOI

Wierlacher S.; Sander W.; Liu M. T. H. Photolysis of Alkylhalodiazirines and Direct Observation of Benzylchlorocarbene in Cryogenic Matrixes. J. Am. Chem. Soc. 1993, 115, 8943–8953. 10.1021/ja00073a008. DOI

Chao H. S. I.; Berchtold G. A. Aromatization of Arene 1,2-oxides. 1,2-Oxides of methyl Phenylacetate and Methyl trans-cinnamate. J. Org. Chem. 1981, 46, 1191–1194. 10.1021/jo00319a029. DOI

Zaykov A.; Felkel P.; Buchanan E. A.; Jovanovic M.; Havenith R. W. A.; Kathir R. K.; Broer R.; Havlas Z.; Michl J. Singlet Fission Rate: Optimized Packing of a Molecular Pair. Ethylene as a Model. J. Am. Chem. Soc. 2019, 141, 17729–17743. 10.1021/jacs.9b08173. PubMed DOI

SAINT Software for CCD Diffractometers; Bruker AXS Inc.: Madison, WI, 2014.

Sheldrick G. M.TWINABS; Bruker Analytical X-ray Systems, Inc.: Madison, WI, 2000.

Sheldrick G. M.SADABS; Bruker Analytical X-ray Systems, Inc.: Madison, WI, 2000.

Sheldrick G. M. SHELXT - Integrated Space-group and Crystal-structure Determination. Acta Crystallogr., Sect. A: Found. Adv. 2015, 71, 3–8. 10.1107/s2053273314026370. PubMed DOI PMC

Sheldrick G. M. A Short History of SHELX. Acta Crystallogr., Sect. A: Found. Crystallogr. 2008, 64, 112–122. 10.1107/S0108767307043930. PubMed DOI

Zhang X.-F.; Zhang Y.; Liu L. Fluorescence Lifetimes and Quantum Yields of Ten Rhodamine Derivatives: Structural Effect on Emission Mechanism in Different Solvents. J. Lumin. 2014, 145, 448–453. 10.1016/j.jlumin.2013.07.066. DOI

Lakowicz J. R.Principles of Fluorescence Spectroscopy, 3rd ed.; Springer: Boston, MA, 2006.

Hermans J. J.; Levinson S. Some Geometrical Factors in Light-Scattering Apparatus. J. Opt. Soc. Am. 1951, 41, 460–465. 10.1364/JOSA.41.000460. DOI

Frisch M. J.; Trucks G. W.; Schlegel H. B.; Scuseria G. E.; Robb M. A.; Cheeseman J. R.; Scalmani G.; Barone V.; Petersson G. A.; Nakatsuji H.; Li X.; Caricato M.; Marenich A. V.; Bloino J.; Janesko B. G.; Gomperts R.; Mennucci B.; Hratchian H. P.; Ortiz J. V.; Izmaylov A. F.; Sonnenberg J. L.; Williams-Young D.; Ding F.; Lipparini F.; Egidi F.; Goings J.; Peng B.; Petrone A.; Henderson T.; Ranasinghe D.; Zakrzewski V. G.; Gao J.; Rega N.; Zheng G.; Liang W.; Hada M.; Ehara M.; Toyota K.; Fukuda R.; Hasegawa J.; Ishida M.; Nakajima T.; Honda Y.; Kitao O.; Nakai H.; Vreven T.; Throssell K.; Montgomery Jr J. A.; Peralta J. E.; Ogliaro F.; Bearpark M. J.; Heyd J. J.; Brothers E. N.; Kudin K. N.; Staroverov V. N.; Keith T. A.; Kobayashi R.; Normand J.; Raghavachari K.; Rendell A. P.; Burant J. C.; Iyengar S. S.; Tomasi J.; Cossi M.; Millam J. M.; Klene M.; Adamo C.; Cammi R.; Ochterski J. W.; Martin R. L.; Morokuma K.; Farkas O.; Foresman J. B.; Fox D. J.. Gaussian 16, revision B.01; Gaussian, Inc.: Wallingford CT, 2016.

Becke A. D. Density-functional thermochemistry. III. The role of exact exchange. J. Chem. Phys. 1993, 98, 5648–5652. 10.1063/1.464913. DOI

Grimme S.; Antony J.; Ehrlich S.; Krieg H. A Consistent and Accurate ab initio Parametrization of Density Functional Dispersion Correction (DFT-D) for the 94 Elements H-Pu. J. Chem. Phys. 2010, 132, 15410410.1063/1.3382344. PubMed DOI

Kendall R. A.; Dunning T. H. Jr.; Harrison R. J. Electron Affinities of the First Row Atoms Revisited. Systematic Basis Sets and Wave Functions. J. Chem. Phys. 1992, 96, 6796–6806. 10.1063/1.462569. DOI

Glendening E. D.; Badenhoop J. K.; Reed A. E.; Carpenter J. E.; Bohmann J. A.; Morales C. M.; Karafiloglou P.; Landis C. R.; Weinhold F.. NBO 7.0; Theoretical Chemistry Institute, University of Wisconsin: Madison, 2018.

Frisch M. J.; Trucks G. W.; Schlegel H. B.; Scuseria G. E.; Robb M. A.; Cheeseman J. R.; Scalmani G.; Barone V.; Petersson G. A.; Nakatsuji H.; Li X.; Caricato M.; Marenich A. V.; Bloino J.; Janesko B. G.; Gomperts R.; Mennucci B.; Hratchian H. P.; Ortiz J. V.; Izmaylov A. F.; Sonnenberg J. L.; Williams-Young D.; Ding F.; Lipparini F.; Egidi F.; Goings J.; Peng B.; Petrone A.; Henderson T.; Ranasinghe D.; Zakrzewski V. G.; Gao J.; Rega N.; Zheng G.; Liang W.; Hada M.; Ehara M.; Toyota K.; Fukuda R.; Hasegawa J.; Ishida M.; Nakajima T.; Honda Y.; Kitao O.; Nakai H.; Vreven T.; Throssell K.; Montgomery J. A. Jr.; Peralta J. E.; Ogliaro F.; Bearpark M. J.; Heyd J. J.; Brothers E. N.; Kudin K. N.; Staroverov V. N.; Keith T. A.; Kobayashi R.; Normand J.; Raghavachari K.; Rendell A. P.; Burant J. C.; Iyengar S. S.; Tomasi J.; Cossi M.; Millam J. M.; Klene M.; Adamo C.; Cammi R.; Ochterski J. W.; Martin R. L.; Morokuma K.; Farkas O.; Foresman J. B.; Fox D. J.. Gaussian 16, revision C.01;Gaussian, Inc.: Wallingford CT, 2016.

Rais D.; Toman P.; Pfleger J.; Acharya U.; Panthi Y. R.; Menšík M.; Zhigunov A.; Thottappali M. A.; Vala M.; Marková A.; Stříteský S.; Weiter M.; Cigánek M.; Krajčovič J.; Pauk K.; Imramovský A.; Zaykov A.; Michl J. Singlet Fission in Thin Solid Films of Bis(thienyl)diketopyrrolopyrroles. ChemPlusChem 2020, 85, 2689–2703. 10.1002/cplu.202000623. PubMed DOI

Nelsen S. F.; Blackstock S. C.; Kim Y. Estimation of Inner Shell Marcus Terms for Amino Nitrogen Compounds by Molecular Orbital Calculations. J. Am. Chem. Soc. 1987, 109, 677–682. 10.1021/ja00237a007. DOI

Freudenreich C.; Samama J. P.; Biellmann J. F. Design of inhibitors from the three-dimensional structure of alcohol dehydrogenase. Chemical synthesis and enzymic properties. J. Am. Chem. Soc. 1984, 106, 3344–3353. 10.1021/ja00323a048. DOI

Hahn B.; Köpke B.; Voß J. Darstellung von Diaryl- und Aryl-tert-butyl-α-thioxoketonen. Liebigs Ann. Chem. 1981, 1981, 10–19. 10.1002/jlac.198119810104. DOI

Okamoto I.; Takahashi Y.; Sawamura M.; Matsumura M.; Masu H.; Katagiri K.; Azumaya I.; Nishino M.; Kohama Y.; Morita N.; Tamura O.; Kagechika H.; Tanatani A. Redox-responsive conformational alteration of aromatic amides bearing N-quinonyl system. Tetrahedron 2012, 68, 5346–5355. 10.1016/j.tet.2012.04.114. DOI

Kaleta J.; Dudič M.; Ludvíková L.; Liška A.; Zaykov A.; Rončevič I.; Mašát M.; Bednárová L.; Dron P. I.; Teat S. J.; Michl J.. Phenyl-Substituted Cibalackrot Derivatives: Synthesis, Structure, and Solution Photophysics ChemRxiv 2023. PubMed PMC

Uncovering intramolecular singlet fission at the root of the dual fluorescence of 1,4-bis(p-nitro-β-styryl)benzene in solution

Phenyl-Substituted Cibalackrot Derivatives: Synthesis, Structure, and Solution Photophysics