196212-27-8Relevant academic research and scientific papers
Self-complementary and narcissistic self-sorting of bis-acridinium tweezers
Jacquot De Rouville, Henri-Pierre,Gourlaouen, Christophe,Heitz, Valérie
, p. 8725 - 8730 (2019)
A molecular tweezer incorporating two acridinium moieties linked by a 1,3-dipyridylbenzene spacer was synthesized in three steps. The formation of its self-complementary dimer in water was demonstrated as a result of π-π stacking and hydrophobic interacti
A Molybdenum(0) Isocyanide Analogue of Ru(2,2′-Bipyridine)32+: A Strong Reductant for Photoredox Catalysis
Büldt, Laura A.,Guo, Xingwei,Prescimone, Alessandro,Wenger, Oliver S.
, p. 11247 - 11250 (2016)
We report the first homoleptic Mo0complex with bidentate isocyanide ligands, which exhibits metal-to-ligand charge transfer (3MLCT) luminescence with quantum yields and lifetimes similar to Ru(bpy)32+(bpy=2,2′-b
A chemically-responsive bis-acridinium receptor
Gosset,Xu,Maurel,Chamoreau,Nowak,Vives,Perruchot,Heitz,Jacquot De Rouville
, p. 4728 - 4734 (2018)
A dicationic receptor based on two acridinium moieties linked by a triphenylene spacer was studied in solution and in the solid state. Recognition moieties, namely acridiniums, were exploited to evidence a host-guest response of the receptor with electron rich guests. Upon addition of methoxide anions, the formation of the bis-acridane form of the receptor was observed. The chemical responsiveness of the receptor to these anions inhibits its recognition properties towards π-donor guests. In addition, the reversibility of the chemical response was demonstrated under acidic conditions.
Synthesis, Structures, and Assembly of Geodesic Phenine Frameworks with Isoreticular Networks of [ n]Cyclo- para-phenylenes
Sun, Zhe,Mio, Tatsuru,Ikemoto, Koki,Sato, Sota,Isobe, Hiroyuki
, p. 3500 - 3507 (2019)
A series of macrocycles were designed by rendering geodesic phenine frameworks in isoreticular networks of [n]cyclo-para-phenylenes. Large, nanometer-sized molecules exceeding molecular weights of 2000 Da were synthesized by five-step transformations incl
Regioselective aromatic borylation in an inert solvent.
Tse,Cho,Smith 3rd.
, p. 2831 - 2833 (2001)
[reaction: see text]. A protocol for performing Rh catalyzed aromatic borylations in cyclohexane has been devised. Borylation at the 5-position of several 1,3-substituted aromatic species ranging from electron-rich (1,3-(NMe(2))(2)C(6)H(4)) to electron-deficient (1,3-(CF(3))(2)C(6)H(4)) yields the corresponding aryl boronate esters. Veratrole was selectively borylated at the 4-position, thus extending regioselectivity to 1,2-substituted benzenes. Selective borylation at the 3-position of an N-protected pyrrole has also been demonstrated, providing a valuable reagent for cross-coupling reactions in a single step.
Unveiling Extreme Photoreduction Potentials of Donor-Acceptor Cyanoarenes to Access Aryl Radicals from Aryl Chlorides
Cao, Jilei,Tang, Xinxin,Toh, Ren Wei,Wang, Han,Wu, Jie,Wu, Xiangyang,Xu, Jinhui,Yang, Xiaona,Yeow, Edwin K. L.,Zhou, Rong
supporting information, p. 13266 - 13273 (2021/09/07)
Since the seminal work of Zhang in 2016, donor-acceptor cyanoarene-based fluorophores, such as 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN), have been widely applied in photoredox catalysis and used as excellent metal-free alternatives to noble metal Ir- and Ru-based photocatalysts. However, all the reported photoredox reactions involving this chromophore family are based on harnessing the energy from a single visible light photon, with a limited range of redox potentials from -1.92 to +1.79 V vs SCE. Here, we document the unprecedented discovery that this family of fluorophores can undergo consecutive photoinduced electron transfer (ConPET) to achieve very high reduction potentials. One of the newly synthesized catalysts, 2,4,5-tri(9H-carbazol-9-yl)-6-(ethyl(phenyl)amino)isophthalonitrile (3CzEPAIPN), possesses a long-lived (12.95 ns) excited radical anion form, 3CzEPAIPN?-*, which can be used to activate reductively recalcitrant aryl chlorides (Ered ≈ -1.9 to -2.9 V vs SCE) under mild conditions. The resultant aryl radicals can be engaged in synthetically valuable aromatic C-B, C-P, and C-C bond formation to furnish arylboronates, arylphosphonium salts, arylphosphonates, and spirocyclic cyclohexadienes.
Photo-induced thiolate catalytic activation of inert Caryl-hetero bonds for radical borylation
K?nig, Burkhard,Wang, Hua,Wang, Shun
supporting information, p. 1653 - 1665 (2021/06/17)
Substantial effort is currently being devoted to obtaining photoredox catalysts with high redox power. Yet, it remains challenging to apply the currently established methods to the activation of bonds with high bond dissociation energy and to substrates with high reduction potentials. Herein, we introduce a novel photocatalytic strategy for the activation of inert substituted arenes for aryl borylation by using thiolate as a catalyst. This catalytic system exhibits strong reducing ability and engages non-activated Caryl–F, Caryl–X, Caryl–O, Caryl–N, and Caryl–S bonds in productive radical borylation reactions, thus expanding the available aryl radical precursor scope. Despite its high reducing power, the method has a broad substrate scope and good functional-group tolerance. Spectroscopic investigations and control experiments suggest the formation of a charge-transfer complex as the key step to activate the substrates.
Modular Synthesis of Organoboron Helically Chiral Compounds: Cutouts from Extended Helices
Full, Julian,Panchal, Santosh P.,G?tz, Julian,Krause, Ana-Maria,Nowak-Król, Agnieszka
supporting information, p. 4350 - 4357 (2021/01/29)
Two types of helically chiral compounds bearing one and two boron atoms were synthesized by a modular approach. Formation of the helical scaffolds was executed by the introduction of boron to flexible biaryl and triaryl derived from small achiral building blocks. All-ortho-fused azabora[7]helicenes feature exceptional configurational stability, blue or green fluorescence with quantum yields (Φfl) of 18–24 % in solution, green or yellow solid-state emission (Φfl up to 23 %), and strong chiroptical response with large dissymmetry factors of up to 1.12×10?2. Azabora[9]helicenes consisting of angularly and linearly fused rings are blue emitters exhibiting Φfl of up to 47 % in CH2Cl2 and 25 % in the solid state. As revealed by the DFT calculations, their P–M interconversion pathway is more complex than that of H1. Single-crystal X-ray analysis shows clear differences in the packing arrangement of methyl and phenyl derivatives. These molecules are proposed as primary structures of extended helices.
A synthetic approach to dimetalated arenes using flow microreactors and the switchable application to chemoselective cross-coupling reactions
Nagaki, Aiichiro,Ashikari, Yosuke,Kawaguchi, Tomoko,Mandai, Kyoko,Aizawa, Yoko
supporting information, p. 17039 - 17047 (2020/11/10)
In spite of their potential utility, the chemistry of dimetalated arenes is still in its infancy because they are extremely difficult to synthesize. We report a novel method of synthesizing arenes bearing a boryl group and a metallic substituent, such as boryl, silyl, stannyl, or zincyl groups, in an integrated flow microreactor based on the generation and reactions of aryllithiums bearing a trialkyl borate moiety. The bimetallic arenes showed a remarkable chemoselectivity in palladium-catalyzed cross-coupling reactions. The selectivity was switched by the selection of the metal species that constitutes the dimetalated arenes as well as appropriate catalysts.
Visible-Light-Induced Ni-Catalyzed Radical Borylation of Chloroarenes
Tian, Ya-Ming,Guo, Xiao-Ning,Krummenacher, Ivo,Wu, Zhu,Nitsch, J?rn,Braunschweig, Holger,Radius, Udo,Marder, Todd B.
supporting information, p. 18231 - 18242 (2020/11/02)
A highly selective and general photoinduced C-Cl borylation protocol that employs [Ni(IMes)2] (IMes = 1,3-dimesitylimidazoline-2-ylidene) for the radical borylation of chloroarenes is reported. This photoinduced system operates with visible light (400 nm) and achieves borylation of a wide range of chloroarenes with B2pin2 at room temperature in excellent yields and with high selectivity, thereby demonstrating its broad utility and functional group tolerance. Mechanistic investigations suggest that the borylation reactions proceed via a radical process. EPR studies demonstrate that [Ni(IMes)2] undergoes very fast chlorine atom abstraction from aryl chlorides to give [NiI(IMes)2Cl] and aryl radicals. Control experiments indicate that light promotes the reaction of [NiI(IMes)2Cl] with aryl chlorides generating additional aryl radicals and [NiII(IMes)2Cl2]. The aryl radicals react with an anionic sp2-sp3 diborane [B2pin2(OMe)]- formed from B2pin2 and KOMe to yield the corresponding borylation product and the [Bpin(OMe)]?- radical anion, which reduces [NiII(IMes)2Cl2] under irradiation to regenerate [NiI(IMes)2Cl] and [Ni(IMes)2] for the next catalytic cycle.
