Browsing by Author "Hsiao, Huan-Chang"

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Cascade One-Pot Synthesis of Orange-Red-Fluorescent Polycyclic Cinnolino[2,3-f]phenanthridin-9-ium Salts by Palladium(II)-Catalyzed C-H Bond Activation of 2-Azobiaryl Compounds and Alkenes
(1970-01-01)
Jayakumar, Jayachandran
;
Vedarethinam, Guganchandar
;
Hsiao, Huan-Chang
;
Sun, Shang-You
;
Chuang, Shih-Ching
Quaternary ammonium salts were synthesized in moderate to good yields through double oxidative C-H bond activation on azobenzenes. The mechanism of the highly regioselective reaction of 2-azobiaryls with alkenes to give orange-red-fluorescent cinnolino[2,3-f]phenanthridin-9-ium salts and 15H-cinnolino[2,3-f]phenanthridin-9-ium-10-ide is proposed to involve ortho C-H olefination of the 2-azobiaryl compound with the alkene, intramolecular aza-Michael addition, concerted metalation-deprotonation (CMD), reductive elimination, and oxidation.
Cascade One-Pot Synthesis of Orange-Red-Fluorescent Polycyclic Cinnolino[2,3-f]phenanthridin-9-ium Salts by Palladium(II)-Catalyzed C-H Bond Activation of 2-Azobiaryl Compounds and Alkenes
(2020-01-07)
Jayakumar, Jayachandran
;
Vedarethinam, Guganchandar
;
Hsiao, Huan-Chang
;
Sun, Shang-You
;
Chuang, Shih-Ching
Quaternary ammonium salts were synthesized in moderate to good yields through double oxidative C-H bond activation on azobenzenes. The mechanism of the highly regioselective reaction of 2-azobiaryls with alkenes to give orange-red-fluorescent cinnolino[2,3-f]phenanthridin-9-ium salts and 15H-cinnolino[2,3-f]phenanthridin-9-ium-10-ide is proposed to involve ortho C-H olefination of the 2-azobiaryl compound with the alkene, intramolecular aza-Michael addition, concerted metalation-deprotonation (CMD), reductive elimination, and oxidation.
Organic bulk heterojunction photovoltaics incorporating cyclopenteno[60]fullerene monoadducts as n-type materials display superior power conversion efficiency than with PC61BM
(1970-01-01)
Tseng, Po-Yen
;
Hsiao, Huan-Chang
;
Hsieh, Cheng-Ming
;
Wu, An-Ju
;
Chuang, Shih-Ching
Organic bulk heterojunction photovoltaics, merely incorporating monoadducts of cyclopenteno[60]fullerenes (CPFs) as n-type materials and P3HT as p-type materials, display superior power conversion efficiency up to 4.6 +/- 0.12%, superseding that with PC61BM/P3HT (3.8 +/- 0.20%) for ca. 20%, under AM 1.5G irradiation?primarily attributed to the lack of homo-conjugation on CPFs and their higher LUMO energy levels.
Palladium(II)-Catalyzed Mono- and Bis-alkenylation of N-Acetyl-2-aminobiaryls through Regioselective C-H Bond Activation
(2018-04-06)
Annamalai, Pratheepkumar
;
Hsu, Kou-Chi
;
Raju, Selvam
;
Hsiao, Huan-Chang
;
Chou, Chih-Wei
We developed palladium-catalyzed oxidative coupling of olefins with N-acyl 2-aminobiaryls through a sequence of ortho C-H bond activation/alkene insertion/reductive elimination. Furthermore, we controlled the selectivity of mono- and bis-alkenylation products with the solvent effect. The developed protocol was promising for a broad substrate scope ranging from activated olefins with a wide variety of functional groups to unactivated olefins.
Palladium-Catalyzed Benzofulvenation of o-Arylanilines through C-H Bond Activation by Using Two Diarylacetylenes as an Implicit Benzofulvene
(2019-02-19)
Raju, Selvam
;
Hsiao, Huan-Chang
;
Thirupathi, Selvakumar
;
Chen, Pei-Ling
;
Chuang, Shih-Ching
We report the first example of Pd(II)-catalyzed highly step- and atom-economical benzofulvenation through free amine-directed ortho C-H bond activation of o-arylanilines. This paper presents a novel, simple, and efficient approach for the synthesis of benzofulvene derivatives from o-arylaniline substrates through C-H bond activation with two diarylacetylenes as an implicit benzofulvene unit. The reactivity of synthesized benzofulvenes toward oxidation was investigated, and they were shown to transform into phenanthridines, oxabenzofulvenes, and fluorescent polycyclics.
Pd-Catalyzed Redox-Neutral C-N Coupling Reaction of Iminoquinones with Electron-Deficient Alkenes without External Oxidants: Access of Tertiary (E)-Enamines and Application to the Synthesis of Indoles and Quinolin-4-ones
(2020-08-21)
Jillella, Raveendra
;
Raju, Selvam
;
Hsiao, Huan-Chang
;
Hsu, Day-Shin
;
Chuang, Shih-Ching
A novel and efficient reductive N-alkenylation of iminoquinones with electron-deficient olefins has been successfully developed by Pd(II)-catalyzed redox-neutral reactions, which provides a synthesis of tertiary (E)-enamines. We further demonstrate that the tertiary enamines can be converted to multifarious N-heterocyclic compounds, indoles, and quinolones in good yields.
Synthesis, Isolation, and Characterization of Mono- and Bis-norbornene-Annulated Biarylamines through Pseudo-Catellani Intermediates
(2019-02-15)
Annamalai, Pratheepkumar
;
Hsiao, Huan-Chang
;
Raju, Selvam
;
Fu, Yi-Hsuan
;
Chen, Pei-Ling
A palladium-catalyzed C-H functionalization of an external ring of N-acyl 2-aminobiaryl with bicyclo[2.2.1]-hept-2-ene (norbornene) via multiple C-H bond activations was developed. This study is the first report of the formation of bis-norbornene annulated biarylamines isomers (syn-3a'/anti-3a' = 36:64) from multiple C-H bond functionalizations. Additionally, nondirected C-H bond functionalization at the C-4' position with alkenes rendered complete C-H functionalization of five C-H bonds that formed a stable hexasubstituted benzene ring.