TY - JOUR AU - Bogner, Marcell M. AU - London, Gábor TI - Aza-annulation reactions extend π-conjugated systems JF - NATURE SYNTHESIS J2 - NAT SYNTH PY - 2024 SN - 2731-0582 DO - 10.1038/s44160-024-00615-4 UR - https://m2.mtmt.hu/api/publication/35416944 ID - 35416944 LA - English DB - MTMT ER - TY - CHAP AU - Kunfi, Attila AU - London, Gábor ED - Reedijk, J. TI - Light-activated Molecular Switches, Machines and Motors T2 - Reference Module in Chemistry, Molecular Sciences and Chemical Engineering PB - Elsevier CY - Waltham (MA) SN - 9780124095472 PY - 2024 DO - 10.1016/B978-0-443-15742-4.00031-4 UR - https://m2.mtmt.hu/api/publication/34827442 ID - 34827442 LA - English DB - MTMT ER - TY - JOUR AU - Meiszter, Enikő AU - Gazdag, Tamás AU - Mayer, Péter József AU - Kunfi, Attila AU - Holczbauer, Tamás AU - Sulyok-Eiler, Máté AU - London, Gábor TI - Revisiting Hafner’s Azapentalenes: The Chemistry of 1,3-Bis(dimethylamino)-2-azapentalene JF - JOURNAL OF ORGANIC CHEMISTRY J2 - J ORG CHEM VL - 89 PY - 2024 IS - 9 SP - 5941 EP - 5951 PG - 11 SN - 0022-3263 DO - 10.1021/acs.joc.3c02564 UR - https://m2.mtmt.hu/api/publication/34821706 ID - 34821706 N1 - Funding Agency and Grant Number: Magyar Tudom?nyos Akad?mia; Lendulet Program of the Hungarian Academy of Sciences [PD 137866, FK 142622]; National Research, Development and Innovation Office, Hungary [NKFIH] [VEKOP-2.3.3-15-2017-00018]; Hungarian Academy of Sciences; European Union; State of Hungary; European Regional Development Fund Funding text: Financial support from the Lendulet Program of the Hungarian Academy of Sciences and the National Research, Development and Innovation Office, Hungary [NKFIH Grants no. PD 137866 (A.K.) and FK 142622 (G.L.)] is gratefully acknowledged. G.L. acknowledges the Janos Bolyai Research Scholarship from the Hungarian Academy of Sciences. KIFU is acknowledged for computational resources. The authors are grateful to Krisztina Nemeth (MS Metabolomics Research Group, Instrumentation Center, Research Centre for Natural Sciences) for HRMS measurements. M.S.-E. acknowledges Veronika Harmat for helpful discussions of crystallographic procedures. Crystallographic studies were supported by grant VEKOP-2.3.3-15-2017-00018 from the European Union and the State of Hungary, cofinanced by the European Regional Development Fund (M.S.-E.). AB - Stable azaheterocyclic derivatives of pentalene have been reported by the group of Hafner in the 1970s. However, these structures remained of low interest until recently, when they started to be investigated in the context of organic light-emitting diodes’ (OLEDs’) development. Herein, we revisit the synthesis of stable azapentalene derivative 1,3-bis(dimethylamino)-2-azapentalene and further explore its properties both computationally and experimentally. Beyond the reproduction and optimization of some previously reported transformations, such as formylation and amine substitution, the available scope of reactions was expanded with azo-coupling, selective halogenations, and cross-coupling reactions. © 2024 The Authors. Published by American Chemical Society. LA - English DB - MTMT ER - TY - JOUR AU - Gazdag, Tamás AU - Meiszter, Enikő AU - Mayer, Péter József AU - Holczbauer, Tamás AU - Ottosson, Henrik AU - Maurer, Andrew B. AU - Abrahamsson, Maria AU - London, Gábor TI - An Exploration of Substituent Effects on the Photophysical Properties of Monobenzopentalenes JF - CHEMPHYSCHEM: A EUROPEAN JOURNAL OF CHEMICAL PHYSICS AND PHYSICAL CHEMISTRY J2 - CHEMPHYSCHEM VL - 25 PY - 2024 IS - 7 PG - 11 SN - 1439-4235 DO - 10.1002/cphc.202300737 UR - https://m2.mtmt.hu/api/publication/34571192 ID - 34571192 N1 - Funding details: Carl Tryggers Stiftelse för Vetenskaplig Forskning, CTS 22 : 2330 Funding details: Magyar Tudományos Akadémia, MTA Funding details: Vetenskapsrådet, VR, 2019‐05618 Funding details: Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, NKFI, FK 142622 Funding details: National Supercomputer Centre, Linköpings Universitet, NSC, 2018‐05973, 2022‐06725 Funding text 1: . Financial support from the Lendület Program of the Hungarian Academy of Sciences and the National Research, Development and Innovation Office, Hungary (NKFIH Grant FK 142622 (G.L.)) is gratefully acknowledged. G.L. acknowledges the János Bolyai Research Scholarship from the Hungarian Academy of Sciences. We are grateful to Krisztina Németh (MS Metabolomics Research Group, Instrumentation Center, HUN‐REN TTK) for HRMS measurements. The Carl Trygger Foundation for a postdoctoral scholarship to P.M. (grant CTS 22 : 2330) and the Swedish Research Council for financial support to H.O. (grant 2019‐05618) are gratefully acknowledged. The computations were enabled by resources provided by the National Academic Infrastructure for Supercomputing in Sweden (NAISS) and the Swedish National Infrastructure for Computing (SNIC) at the National Supercomputer Center (NSC) Linköping, partially funded by the Swedish Research Council through grant agreements no. 2022‐06725 and no. 2018‐05973 AB - Monobenzopentalenes have received moderate attention compared to dibenzopentalenes, yet their accessibility as stable, non‐symmetric structures with diverse substituents could be interesting for materials applications, including molecular photonics. Recently, monobenzopentalene was considered computationally as a potential chromophore for singlet fission (SF) photovoltaics. To advance this compound class towards photonics applications, the excited state energetics must be characterized, computationally and experimentally. In this report we synthesized a series of stable substituted monobenzopentalenes and provided the first experimental exploration of their photophysical properties. Structural and opto‐electronic characterization revealed that all derivatives showed 1H NMR shifts in the olefinic region, bond length alternation in the pentalene unit, low‐intensity absorptions reflecting the ground‐state antiaromatic character and in turn the symmetry forbidden HOMO‐to‐LUMO transitions of ~2 eV and redox amphotericity. This was also supported by computed aromaticity indices (NICS, ACID, HOMA). Accordingly, substituents did not affect the fulfilment of the energetic criterion of SF, as the computed excited‐state energy levels satisfied the required E(S1)/E(T1) > 2 relationship. Further spectroscopic measurements revealed a concentration dependent quenching of the excited state and population of the S2 state on the nanosecond timescale, providing initial evidence for unusual photophysics and an alternative entry point for singlet fission with monobenzopentalenes. LA - English DB - MTMT ER - TY - JOUR AU - Kalapos, Péter Pál AU - Kunfi, Attila AU - Bogner, Marcell M. AU - Holczbauer, Tamás AU - Kochman, Michał Andrzej AU - Durbeej, Bo AU - London, Gábor TI - Salicylideneaniline/Dithienylethene Hybrid Molecular Switches: Design, Synthesis, and Photochromism JF - JOURNAL OF ORGANIC CHEMISTRY J2 - J ORG CHEM VL - 89 PY - 2024 IS - 1 SP - 16 EP - 26 PG - 11 SN - 0022-3263 DO - 10.1021/acs.joc.3c00828 UR - https://m2.mtmt.hu/api/publication/34450815 ID - 34450815 LA - English DB - MTMT ER - TY - JOUR AU - Dobszay, Rita AU - Mayer, Péter József AU - Holczbauer, Tamás AU - Kunfi, Attila AU - Stirling, András AU - London, Gábor TI - The π‐molecular complex of biphenylene and tetracyanoethylene JF - HELVETICA CHIMICA ACTA J2 - HELV CHIM ACTA VL - 106 PY - 2023 IS - 9 PG - 13 SN - 0018-019X DO - 10.1002/hlca.202300079 UR - https://m2.mtmt.hu/api/publication/34112865 ID - 34112865 N1 - MTA TTK Lendület Functional Organic Materials Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok krt. 2, Budapest, HU-1117, Hungary Institute of Organic Chemistry, Centre for Structural Science, Research Centre for Natural Sciences, Magyar Tudósok krt. 2, Budapest, HU-1117, Hungary Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok krt. 2, Budapest, HU-1117, Hungary Department of Chemistry, Eszterházy Károly University, Leányka utca 6, Eger, HU-3300, Hungary Export Date: 18 February 2024 CODEN: HCACA Correspondence Address: London, G.; MTA TTK Lendület Functional Organic Materials Research Group, Magyar Tudósok krt. 2, Hungary; email: london.gabor@ttk.hu Correspondence Address: Stirling, A.; Institute of Organic Chemistry, Magyar Tudósok krt. 2, Hungary; email: stirling.andras@ttk.hu Chemicals/CAS: phenazone, 60-80-0; tetracyanoethylene, 670-54-2 Funding details: Magyar Tudományos Akadémia, MTA, LENDULET_2018_355 Funding details: Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, NKFIH, FK 142622, K 132236, PD 137866 Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding details: National Research, Development and Innovation Office Funding text 1: Financial support from the Hungarian Academy of Sciences through the Lendület Program (LENDULET_2018_355) (G.L.) and the National Research, Development and Innovation Office, Hungary (NKFIH Grants No. PD 137866 (A.K.), FK 142622 (G.L.) and K 132236 (A.S.)) is acknowledged. P.J.M. acknowledges the professional support of the Doctoral Student Scholarship Program of the Co‐operative Doctoral Program of the Ministry of Innovation and Technology financed from the National Research, Development and Innovation Fund. Dr. Attila Domján and Dr. Gábor Turczel (RCNS) are acknowledged for valuable discussions. AB - The investigation of the biphenylene (BP)‐tetracyanoethylene (TCNE) π‐molecular complex is reported. The first study on this complex appeared in 1961 and was considered as a charge transfer complex with a symmetric, co‐planar arrangement of the components. Moreover, it was assumed that this arrangement is not only dictated by the formation of a Mulliken‐type donor‐acceptor complex, but also by the electronic stabilization of the “cyclobutadieneoid” central ring of biphenylene through complex formation. Yet, crystal structure and associated computational analysis have not verified these predictions so far. We found that factors other than charge‐transfer interactions are most influential in the crystal formation. The low association constant in solution, and the weak interaction between the components in the 1:1 crystal structure point towards the low contribution of charge transfer interactions to their binding. Nevertheless, the presence of these interaction is hinted by the color of its solution and verified by theoretical calculations. Furthermore, Nucleus Independent Chemical Shift (NICS) calculations were carried out to characterize potential changes in the (anti)aromatic character of BP upon complex formation. The NICS(0) values of the rings of BP exhibit tiny changes both in the BP‐TCNE dimer and in the crystal, which also suggests weak electronic interactions between them. LA - English DB - MTMT ER - TY - JOUR AU - Mayer, Péter József AU - Botlik, Bence B. AU - Meiszter, Enikő AU - Németh, Krisztina AU - Schürmann, Christian J. AU - Holczbauer, Tamás AU - London, Gábor TI - Vertical π-extension of dibenzopentalene: a combined experimental and computational study of a phenanthreno-benzopentalene derivative JF - COMPUTATIONAL AND THEORETICAL CHEMISTRY J2 - COMPUT THEOR CHEM VL - 1224 PY - 2023 PG - 7 SN - 2210-271X DO - 10.1016/j.comptc.2023.114113 UR - https://m2.mtmt.hu/api/publication/33735013 ID - 33735013 LA - English DB - MTMT ER - TY - JOUR AU - Mayer, Péter József AU - London, Gábor TI - Stable Monoareno-pentalenes with Two Olefinic Protons JF - ORGANIC LETTERS J2 - ORG LETT VL - 25 PY - 2023 IS - 1 SP - 42 EP - 46 PG - 5 SN - 1523-7060 DO - 10.1021/acs.orglett.2c03752 UR - https://m2.mtmt.hu/api/publication/33565543 ID - 33565543 LA - English DB - MTMT ER - TY - JOUR AU - Adorján, Áron AU - Mayer, Péter József AU - Szabó, Pál Tamás AU - Holczbauer, Tamás AU - London, Gábor TI - Metal-free synthesis of indenone derivatives from ortho -alkynylaryl ketones mediated by the combination of dialkyl phosphonates and CBr 4 JF - SYNTHETIC COMMUNICATIONS J2 - SYNTHETIC COMMUN VL - 52 PY - 2022 IS - 19-20 SP - 1956 EP - 1966 PG - 11 SN - 0039-7911 DO - 10.1080/00397911.2022.2122725 UR - https://m2.mtmt.hu/api/publication/33204119 ID - 33204119 LA - English DB - MTMT ER - TY - JOUR AU - Kalapos, Péter Pál AU - Mayer, Péter József AU - Gazdag, Tamás AU - Demeter, Attila AU - Oruganti, Baswanth AU - Durbeej, Bo AU - London, Gábor TI - Photoswitching of Local (Anti)Aromaticity in Biphenylene-Based Diarylethene Molecular Switches. JF - JOURNAL OF ORGANIC CHEMISTRY J2 - J ORG CHEM VL - 87 PY - 2022 IS - 15 SP - 9532 EP - 9542 PG - 11 SN - 0022-3263 DO - 10.1021/acs.joc.2c00504 UR - https://m2.mtmt.hu/api/publication/33003988 ID - 33003988 AB - Photoinduced tuning of (anti)aromaticity and associated molecular properties is currently in the focus of attention for both tailoring photochemical reactivity and designing new materials. Here, we report on the synthesis and spectroscopic characterization of diarylethene-based molecular switches embedded in a biphenylene structure composed of rings with different levels of local (anti)aromaticity. We show that it is possible to modulate and control the (anti)aromatic character of each ring through reversible photoswitching of the aryl units of the system between open and closed forms. Remarkably, it is shown that the irreversible formation of an annulated bis(dihydro-thiopyran) side-product that hampers the photoswitching can be efficiently suppressed when the aryl core formed by thienyl groups in one switch is replaced by thiazolyl groups in another. LA - English DB - MTMT ER -