The Ravat Group: Chemistry of Molecular Nanosystems



    Bis-[cyclic (alkyl)(amino)carbene]s derived diradicals

    Nayak, M. K.;  Elvers, B. J.;  Mehta, S.;  Krummenacher, I.;  Mondal, A.*;  Braunschweig, H.*;  Schulzke, C.*;  Ravat, P.*; Jana, A.*

    Chem. Commun. 2024.
     DOI: 10.1039/D3CC05779H


    Push–pull [7]helicene diimide: excited-state charge transfer and solvatochromic circularly polarised luminescence

    Saal, F.;  Swain, A.;  Schmiedel, A.;  Holzapfel, M.;  Lambert, C.; Ravat, P.*

    Chem. Commun. 2023.
     DOI: 10.1039/D3CC04470J


    Aza[7]helicene Functionalized Triphenylmethyl Radicals with Circularly Polarized Doublet Emission

    Gross, M.;  Zhang, F.;  Arnold, M. E.;  Ravat, P.*; Kuehne, A. J. C.*

    Adv. Optical Mater. 2023. DOI: 10.1002/adom.202301707


    Bis-Olefin Based Crystalline Schlenk Hydrocarbon Diradicals with a Triplet Ground State

    Saha, P.; Chrysochos, N.; Elvers, B. J.; Pätsch, S.; Uddin, S. I.; Krummenacher, I.; Nandeshwar, M.; Mishra, A.; Raman, K. V.; Rajaraman, G.*; Prabusankar, G.*; Braunschweig, H.*; Ravat, P. *; Schulzke, C.*; Jana, A.* 

    Angew. Chem. Int. Ed., 2023, e202311868.  DOI: 10.1002/anie.202311868


    Introducing an orthogonally polarized electron-rich alkene: synthesis of a zwitterionic boron-containing π-conjugated system

    Chrysochos, N.; Pätsch, S.; Elvers, B. J.; Krummenacher, I.; Muneshwar, N.; Ganesan, P.*; Braunschweig, H.*; Schulzke, C.*; Ravat, P.*; Jana, A.* 

    Chem. Commun. 2023DOI: 10.1039/D3CC03975G


    Pyrene bridged double[7]helicene embedded with a heptagonal ring

    Swain, A.; Ravat, P.* 

    Org. Chem. Front.2023. Organic Chemistry Frontiers Emerging Investigator Series

    DOI: 10.1039/D3QO00386H


    Dimethylnonacethrene – en route to a magnetic switch

    Čavlović, D.; Blacque, O.; Krummenacher, I.; Braunschweig, H.; Ravat, P.*; Juríček, M.* 

    Chem. Commun.,  2023. Chemical Communications HOT Articles 2023

    DOI: 10.1039/D3CC01301D


    Efficient Narrowband Circularly Polarized Light Emitters Based on 1,4-B,N-embedded Rigid Donor–Acceptor Helicenes

    Zhang, F.; Rauch, F.; Swain A.; Marder T.; Ravat, P.*

    Angew. Chem. Int. Ed., 2023.

    DOI: 10.1002/anie.202218965J


    A bis-NHC-CAAC dimer derived dicationic diradical

    Nayak, M. K.;  Sarkar, P.;  Elvers, B. J.;  Mehta, S.;  Zhang, F. M.;  Chrysochos, N. D.;  Krummenacher, I.;  Vijayakanth, T.;  Narayanan, R. S.;  Dolai, R.;  Roy, B. M.;  Malik, V. M.;  Rawat, H.;  Mondal, A.*;  Boomishankar, R.*;  Pati, S. K.*;  Braunschweig, H.*;  Schulzke, C.*;  Ravat, P.*; Jana, A.*

    Chem. Sci. 2022. Highlight in ChemistryViews.

    DOI: 10.1039/D2SC03937K


    Nonacethrene Unchained: A Cascade to Chiral Contorted Conjugated Hydrocarbon with Two sp3-Defects 

    Čavlović D.; Häussinger D.; Blacque O.; ; Ravat, P.*; Juríček M.*

    JACS Au, 2022, 2, 1616–1626. ACS Editors’ Choice

    DOI: 10.1021/jacsau.2c00190 


    Pyrene-Fused [7]Helicenes Connected via Hexagonal and Heptagonal Rings: Stereospecific Synthesis and Chiroptical Properties

    Swain, A.; Radacki, K.; Holger Braunschweig, H.; Ravat, P.*

    J. Org. Chem. 2022, 87, 993–1000.



    De Novo Synthesis of Free-Standing Flexible 2D Intercalated Nanofilm Uniform over Tens of cm2 

    Ravat, P.;  Uchida, H.;  Sekine, R.;  Kamei, K.;  Yamamoto, A.;  Konovalov, O.;  Tanaka, M.;  Yamada, T.;  Harano, K.; Nakamura, E.

    Adv. Mater. 20222106465. Special Issue: Organic Semiconductors

    DOI: 10.1002/adma.202106465


    Diamidocarbene-Based Thiele and Tschitschibabin Hydrocarbons: Carbonyl Functionalized Kekulé Diradicaloids 

    Maiti, A.;  Sobottka, S.;  Chandra, S.;  Jana, D.;  Ravat, P.*;  Sarkar, B.*; Jana, A.*

    J. Org. Chem. 2021, 86, 16464–16472. 

    DOI: 10.1021/acs.joc.1c01827


    Zinc-[7]helicenocyanine and Its Discrete π-Stacked Homochiral Dimer

    Zhang, F.; Radacki, K.; Braunschweig, H.; Lambert, C.; Ravat, P.*

    Angew. Chem. Int. Ed. 2021, 60, 23656–23660. 

    DOI: 10.1002/anie.202109380


    Imide-Functionalized Helical PAHs: A Step towards New Chiral Functional Materials

    Saal, F.; Ravat, P.*

    SynLett2021, 32, 1879–1890. 

    DOI: 10.1055/a-1616-5643


    Anionic Boron- and Carbon-Based Hetero-Diradicaloids Spanned by a p-Phenylene Bridge

    Maiti, A.; Zhang, F.; Krummenacher, I.; Bhattacharyya, M.; Mehta, S.; Moos, M.; Lambert, C.; Engels, B.*; Mondal, A.*; Braunschweig, H.*; Ravat, P.*; Jana, A.*

    J. Am. Chem. Soc. 2021, 143, 10, 3687–3692.  

    DOI: 10.1021/jacs.0c12624 


    Nano- and Microspheres Containing Inorganic and Biological Nanoparticles: Self-Assembly and Electron Tomographic Analysis

    Sekine, R.; Ravat, P.; Yanagisawa, H.; Liu, C.; Kikkawa, M.; Harano, K.; Nakamura, E.

    J. Am. Chem. Soc. 2021143, 2822–2828. 

    DOI: 10.1021/jacs.0c11944


    C2- and C1-Symmetric Configurationally Stable Pyrene-Fused [5]Helicenes Connected via Hexagonal and Heptagonal Rings

    Swain, A.; Kolanji, K.; Christoph, S.; Ravat, P.*

    Org. Lett. 2021, 23, 1339–1343.

    DOI: 10.1021/acs.orglett.1c00005


    Carbo[n]helicenes Restricted to Enantiomerize: An Insight into the Design Process of Configurationally Stable Functional Chiral PAHs 

    Ravat, P.* 

    Chem. Eur. J. 202127, 3957–3967.  



    [n]Helicene Diimides (n = 5, 6, and 7): Through-Bond versus Through-Space Conjugation

    M.Saal, F.; Zhang, F.; Holzapfel, M.; Stolte, M.;  Michail, E.; Moos, M.; Schmiedel, A.;  Krause, A.-M.; Lambert, C.; Würthner, F.; Ravat, P.*

    J. Am. Chem. Soc.2020, 142, 21298–21303. 

    DOI: 10.1021/jacs.0c11053


    Benzo[cd]triangulene: A Spin 1/2 Graphene Fragment

    Ravat, P.*; Blacque, O.; Juríček, M.*

    J. Org. Chem.  2020, 85, 92–100. 

    DOI: 10.1021/acs.joc.9b02163 


    Stereospecific Synthesis and Photophysical Properties of Propeller-Shaped C90H48 PAH

    Zhang, F.; Michail, E.; Saal, F.; Krause, A.-M.; Ravat, P.* 

    Chem. Eur. J. 2019, 25, 16241–16245 . DOI: 10.1002/chem.201904962  


    Forbidden Electrocyclizations of Diradicaloids

    Šolomek, T.; Ravat, P.; Juríček, M. 

    Trends in Chemistry 20197, 705-706. DOI: 10.1016/j.trechm.2019.08.005  


    Helicenes as Chiroptical Photoswitches

    Ravat, P.; Šolomek, T.; Juríček, M. 

    ChemPhotoChem 2019, 3, 180-186. DOI: 10.1002/cptc.201800229


    Dimethylcethrene: A Chiroptical Diradicaloid Photoswitch

    Ravat, P.; Šolomek, T.; Häussinger, D.; Olivier, B.; Juríček, M. 

    J. Am. Chem. Soc. 2018, 140, 10839-10847. DOI: 10.1021/jacs.8b05465 


    Cethrene: The Chameleon of Woodward–Hoffmann Rules

    Šolomek, T.; Ravat, P.; Mou, Z.; Kertesz, M.; Juríček, M.

    J. Org. Chem. 2018, 83, 4769−4774. DOI: 10.1021/acs.joc.8b00656


    Configurational Stability of [5]Helicenes

    Ravat, P.; Hinkelmann, R.; Steinebrunner, D.; Prescimone, A.; Bodoky, I.; Juríček, M.

    Org. Lett. 2017, 19, 3707−3710.DOI: 10.1021/acs.orglett.7b01461    


    Mixed Phenyl and Thiophene Oligomers for Bridging Nitronyl Nitroxides

    Kolanji, K.; Ravat, P.; Bogomyakov, A.; Ovcharenko, V.; Schollmeyer, D.; Baumgarten, M.

    J. Org. Chem. 2017, 82, 7764−7773. DOI: 10.1021/acs.joc.7b00435


    π-Extended and Curved Anti-Aromatic Polycyclic Hydrocarbons

    Liu, J.; Ma, J.; Zhang, K.; Ravat, P.; Machata, P.; Avdoshenko, S. M.; Hennersdorf, F.; Komber, H.; Pisula, W.; Weigand, J. J.; Popov, A. A.; Berger, R.; Müllen, K.; Feng, X.

    J. Am. Chem. Soc. 2017, 139, 7513−7521. DOI: 10.1021/jacs.7b01619 Highlighted in Synfacts 2017, 13, 0931.  


    Spin-Delocalization in a Helical Open-Shell Hydrocarbon

    Ravat, P.; Ribar, P.; Rickhaus, M.; Häussinger, D.; Neuburger, M.; Juríček, M.

    J. Org. Chem. 2016, 81, 12303−12317. DOI: 10.1021/acs.joc.6b02246 ACS Editors’ Choice.


    Unraveling the Mark of Surface Defects on a Spinterface: the Nitronyl Nitroxide/TiO2(110) interface

    Kakavandi, R.; Calzolari, A.; Borozdina, Y. B.; Ravat, P.; Chassé, T.; Baumgarten, M.; Casu, M. B.

    Nano Res. 2016, 9, 3515−3527. DOI: 10.1007/s1227 


    Biradicaloid with a Twist: Lowering the Singlet–Triplet Gap

    Ravat, P.; Šolomek, T.; Ribar P.; Juríček, M.

    Synlett 2016, 27, 1613−1617. Cover Article. DOI: 10.1055/s-0035-1561447     


    Cethrene: A Helically Chiral Biradicaloid Isomer of Heptazethrene

    Ravat, P.; Šolomek, T.; Rickhaus, M.; Häussinger, D.; Neuburger, M.; Baumgarten, M.; Juríček, M.

    Angew. Chem. Int. Ed. 2016, 55, 1183−1187. DOI: 10.1002/anie.201507961 Highlighted in Chimia 2016, 70, 207 


    Positional Isomers of Tetramethoxypyrene-Based Mono- and Biradicals

    Ravat, P.; Baumgarten, M.

    J. Phys. Chem. B 2015, 119, 13649−13655. DOI: 10.1021/acs.jpcb.5b03056     


    Tetrabenzo[a,f,j,o]perylene: A Polycyclic Aromatic Hydrocarbon With An Open-Shell Singlet Biradical Ground State

    Liu, J.; Ravat, P.; Wegner, M.; Baumgarten, M; Feng, X.; Müllen, K.

    Angew. Chem. Int. Ed. 2015, 54, 12442−12446. DOI: 10.1002/anie.201502657


    Equivalence of Ethylene and Azo-Bridges in the Modular Design of Molecular Complexes: The Role of Weak Interactions

    Ravat, P.; SeethaLekshmi, S.; Biswas, S. N.; Nandy, P.; Varughese, S.

    Cryst. Growth Des. 2015, 15, 2389−2401. DOI: 10.1021/acs.cgd.5b00183 


    Electronic Structure and Stability of Fluorophore-Nitroxide Radicals from Ultra High Vacuum to Air Exposure

    Kakavandi, R.; Ravat, P.; Savu, S.; Borozdina, Y.; Baumgarten, M.; Casu, B.

    ACS Appl. Mater. Interfaces 2015, 7, 1685−1692. DOI: 10.1021/am508854u    


    Tschitschibabin type Biradicals: Benzenoid or Quinoid?

    Ravat, P.; Baumgarten, M.

    Phys. Chem. Chem. Phys. 2015, 17, 983−991. DOI: 10.1039/C4CP03522D 


    Positive Magneto-LC Effect in Conjugated Spin-Bearing Hexabenzocoronene

    Ravat, P.; Marszalek, T.; Pisula, W.; Müllen, K.; Baumgarten, M.

    J. Am. Chem. Soc. 2014, 136, 12860−12863. DOI: 10.1021/ja507421x  
    Highlighted in Nachrichten aus der Chemie 2015, 63, 266.


    Breaking the Semi-Quinoid Structure: Spin-Switching from Strongly Coupled Singlet to Polarized Triplet State

    Ravat, P.; Teki, Y.; Ito, Y.; Gorelik, E.; Baumgarten, M.

    Chem. Eur. J. 2014, 20, 12041−12045. DOI: 10.1002/chem.201403338 


    Crystal Engineering of Tolane Bridged Nitronyl Nitroxide Biradicals: Candidates for Quantum Magnets

    Ravat, P.; Borozdina, Y.; Ito, Y.; Enkelmann, V.; Baumgarten, M.

    Cryst. Growth Des. 2014, 14, 5840−5846. DOI: 10.1021/cg5010787


    Synthesis of Nitrogen-Doped ZigZag-Edge Peripheries: Dibenzo-9a-azaphenalene as Repeating Unit

    Berger, R.; Giannakopoulos, A.; Ravat, P.; Wagner, M.; Beljonne, D.; Feng, X.; Müllen, K.

    Angew. Chem. Int. Ed. 2014, 53, 10520−10524. DOI: 10.1002/anie.201403302  Highlighted in Synfacts 2014, 10, 1158.


    Tetramethoxypyrene-Based Biradical Donors with Tunable Physical and Magnetic Properties 

    Ravat, P.; Ito, Y.; Gorelik, E.; Enkelmann, V.; Baumgarten, M.

    Org. Lett. 2013, 15, 4280−4283. DOI: 10.1021/ol4015859