Nachrichten aus der Chemie, Год журнала: 2023, Номер 71(9), С. 67 - 69
Опубликована: Авг. 31, 2023
Abstract Helicene erzeugen starke asymmetrische Effekte – vorausgesetzt, man gewinnt sie enantiomerenrein. Forschungsgruppen haben nun Wege gefunden, um und Heterohelicene asymmetrisch herzustellen.
Nature Communications, Год журнала: 2024, Номер 15(1)
Опубликована: Янв. 25, 2024
Abstract Catalytic asymmetric synthesis of helically chiral molecules has remained an outstanding challenge and witnessed fairly limited progress in the past decades. Current methods to construct such compounds almost entirely rely on catalytic enantiocontrolled fused-ring system extension. Herein, we report a direct terminal peri -functionalization strategy, which allows for efficient assembling 1,12-disubstituted [4]carbohelicenes via organocatalyzed enantioselective amination reaction 2-hydroxybenzo[ c ]phenanthrene derivates with diazodicarboxamides. The key feature this approach is that stereochemical information catalyst could be transferred into not only helix sense but also remote C-N axial chirality products, thus enabling [4]- [5]helicenes both structural diversity complexity good efficiency excellent enantiocontrol. Besides, large-scale preparations representative transformations helical products further demonstrate practicality protocol. Moreover, DFT calculations reveal hydrogen bonds C-H---π interactions between substrates contribute ideal control.
Язык: Английский
Процитировано
13
Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(6), С. 1858 - 1895
Опубликована: Янв. 1, 2024
This review is planned to provide a comprehensive overview of the progress made in design and development chiral ligands for asymmetric gold catalysis.
Язык: Английский
Процитировано
13
Chemistry - A European Journal, Год журнала: 2023, Номер 29(70)
Опубликована: Авг. 31, 2023
Herein, we report configurationally stable singly-truncated (ST) and structurally flexible doubly-truncated (DT) helically chiral compounds derived from azabora[7]helicenes by a hypothetical removal of single or two C=C double bonds. The constitutional isomers were synthesized either benzoisoquinoline (BIQ) phenantherene building blocks the corresponding biaryls in excellent yields to give azabora[5]helicenes with pendant phenyl ring at sterically hindered position. These systems highlight electronic impact nitrogen donor substitution disrupted BIQ moiety (STN) possess remarkable photoluminescence quantum up 0.53 solid state blue emission solution dissymmetry factors ca. 3×10-3 . Upon cooling 79 K all exhibit phosphorescence lifetimes 0.5 s. A methyl complex azabora[7]helicene showing configurational stability was used as inducer embedded an emissive polymer (F8BT) produce circularly polarized organic light emitting diodes electroluminescence factor gEL 0.54.
Язык: Английский
Процитировано
9
Accounts of Chemical Research, Год журнала: 2025, Номер unknown
Опубликована: Апрель 2, 2025
ConspectusAromatic rings are fundamental structural motifs found in natural products, synthetic intermediates, pharmaceuticals, agrochemicals, and functional materials. While transformations at the periphery of these well-established, modifying their core frameworks has remained an underexplored frontier. Our group pioneered concept, termed "aromatic metamorphosis", enabling skeletal aromatic by replacing endocyclic atom with a different or inserting into rings, which leads to novel strategies diverse molecular architectures.The concept metamorphosis was first demonstrated stepwise conversion dibenzothiophenes dibenzofurans triphenylenes. These transformations, facilitated palladium nickel catalysts, involve strategic activation robust C-S C-O bonds as key steps. Next, approach extended two-step conversions carbazoles, dibenzophospholes, fluorenes, etc., oxidation corresponding sulfones subsequent sequential inter- intramolecular nucleophilic substitution reactions. new routes have provided efficient access optoelectronic Especially, SNAr-based construction heterohelicene library systematic variation atoms. This strategy revolutionized way libraries constructed enables rapid discovery molecules.In addition substitutions, ring-expanding through insertion also been explored. We developed nickel-catalyzed boron benzofurans, generating benzoxaborins, important scaffolds for medicinal chemistry. catalytic transformation successfully scaled industrial synthesis companies, demonstrates practical utility metamorphosis. Furthermore, manganese-catalyzed lithium-metal-promoted methodologies expanded ranges heteroatoms inserted cleaved, providing methods heterocycles diversity element compositions.Reductive dilithiation thiophenes efficiently yields 1,4-dilithiobutadienes, react variety electrophiles produce series nonbiogenic heteroles, such boroles, phospholes, siloles. In principle, this method should allow sulfur readily available be replaced any is therefore considered ideal example terms chemical spaces elements.Aromatic proposes many synthons retrosynthetic disconnections that defy conventional wisdom organic synthesis. By making full use metamorphosing skeleton, can directly minimal effort time investment. Its applications span from pharmaceuticals materials science, paving paradigm design well strategy.
Язык: Английский
Процитировано
0
Science Advances, Год журнала: 2024, Номер 10(47)
Опубликована: Ноя. 22, 2024
Despite the considerable potential applications for helically chiral molecules across various sectors, their catalytic asymmetric synthesis remains nascent and has seen very limited advancement compared to that of central axial compounds, primarily owing scarcity available starting materials immense challenges associated with achieving stereochemical control. Herein, we report an innovative approach facile kinetic resolution uniquely structured stereochemically complex helical polycyclic phenols by using a steric hindrance–regulated enantioselective dearomative amination reaction. The distinguished aspects this method include exceptional stability dearomatized products impressive versatility recovered substrates in construction enantioenriched frameworks. This work showcases strategic incorporation appropriate groups near reaction site electron-rich aromatic compound can indeed enable interrupted Friedel-Crafts reaction, thus opening alternate avenue study dearomatization nonfunctionalized arenes.
Язык: Английский
Процитировано
2
Chemistry - A European Journal, Год журнала: 2023, Номер 29(48)
Опубликована: Май 24, 2023
A series of substituted derivatives tetraaza[7]helicenes were synthesized and the influence substitution on their photophysical photoredox-catalytic properties was studied. The combination high fluorescence quantum yields up to 0.65 circularly polarized luminescence (CPL) activity results in CPL brightness values (BCPL ) that are among highest recorded for [7]helicenes so far. sulfonylation/hetarylation reaction using cyanopyridines as substrates photoinduced electron transfer (PET) from excited helicenes conducted test viability photoredox catalysis. DFT calculations predict introduction withdrawing substituents yield more oxidizing catalysts.
Язык: Английский
Процитировано
5
The Chemical Record, Год журнала: 2023, Номер 23(11)
Опубликована: Июль 12, 2023
Abstract Carbeniophosphines [R 2 C + −PR ] and phosphonium ylides 3 P −CR − are two complementary classes of carbon‐phosphorus based ligands defined by their unique donor properties. Indeed, while carbeniophosphines electron‐poor P‐ligands due to the positioning a positive charge near coordinating P‐atom, electron‐rich C‐ligands presence negatively charged C‐atom. Based on this knowledge, account summarizes our recent contribution these ligands, in particular strategies developed lower character enhance that ylides. This led us design, at both extremities donating scale, extremely exemplified imidazoliophosphonites −P(OR) dicarbeniophosphines [(R ) −PR], illustrated pincer architectures exhibiting several ylide extremities. In context analogy, closely related cases where C‐atom NHC ligand is close proximity charges, coordinated through its P‐atom also discussed. An overview synthetic methods, properties, general reactivity electronic structure all C,P‐based species presented here.
Язык: Английский
Процитировано
3
Organic & Biomolecular Chemistry, Год журнала: 2024, Номер 22(35), С. 7154 - 7163
Опубликована: Янв. 1, 2024
A series of thiabridged [5]helicenes with exceptional configurational stability are obtained via organocatalysis. The optical and CSP-HPLC resolution reported the chiroptical properties studied.
Язык: Английский
Процитировано
0
Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(20), С. 5798 - 5805
Опубликована: Янв. 1, 2024
Rhodium-catalyzed C–H alkynylation to synthesize 1- and 1,7-di-alkynylated BODIPYs was reported, where the 8-appended pyrrole moiety acts as a directing group. Furthermore, photoinduced cyclization of alkynylated products has been also explored.
Язык: Английский
Процитировано
0
Nachrichten aus der Chemie, Год журнала: 2023, Номер 71(9), С. 67 - 69
Опубликована: Авг. 31, 2023
Abstract Helicene erzeugen starke asymmetrische Effekte – vorausgesetzt, man gewinnt sie enantiomerenrein. Forschungsgruppen haben nun Wege gefunden, um und Heterohelicene asymmetrisch herzustellen.
Процитировано
0