33538-11-3Relevant academic research and scientific papers
Trimethyl borate/magnesium halide complex-induced one-pot homologation reactions of isoquinoline with dialkyl-TMP-zincate
Seo, Hye Ji,Namgoong, Sung Keon
, p. 3594 - 3598 (2012)
Novel one-pot homologation reactions of isoquinoline with lithium dialkyl-TMP-zincate?2MgBrCl/trimethyl borate are described. 1-Alkylisoquinolines (2, 3A, 4A, 5A, 6, and 7) and 1-alkyl-3,4- dihydroisoquinolines (3B, 4B, and 5B) are easily prepared under t
Metal-Organic Layers for Synergistic Lewis Acid and Photoredox Catalysis
Quan, Yangjian,Lan, Guangxu,Fan, Yingjie,Shi, Wenjie,You, Eric,Lin, Wenbin
, p. 1746 - 1751 (2020)
We report the design of a new multifunctional metal-organic layer (MOL), Hf12-Ir-OTf, comprising triflate (OTf)-capped Hf12 secondary building units (SBUs) and photosensitizing Ir(DBB)[dF(CF3)ppy]2+ [DBB-Ir-F, DBB = 4,4′-di(4-benzoato)-2,2′-bipyridine; dF(CF3)ppy = 2-(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine] bridging ligands. Hf12-Ir-OTf effectively catalyzed dehydrogenative cross-couplings of heteroarenes with ethers, amines, and unactivated alkanes with turnover numbers of 930, 790, and 950, respectively. Hf12-Ir-OTf also competently catalyzed late-stage functionalization of bioactive and drug molecules such as caffeine, Fasudil, and Metyrapone. The superior catalytic performance of Hf12-Ir-OTf over a mixture of photoredox catalyst and stoichiometric amounts of Br?nsted acids or substoichiometric amounts (20 mol %) of Lewis acids is attributed to the close proximity (1.2 nm) between photoredox and Lewis acid catalysts in Hf12-Ir-OTf, which not only facilitates the reaction between the carbon radical and the activated heteroarene but also accelerates the electron transfer from the nitrogen radical intermediate to the Ir(IV) species in the catalytic cycle.
Cyclotransformation of azinium salts into hydrogenated cyclic alkylamino ketones
Terenin,Ivanov
, p. 1300 - 1306 (2005)
A study was carried out on the nucleophilic cyclotransformation of pyrrolo[1,2-a]pyrazinium salts and isoquinolinium salts containing a methyl group in the α-position. A method for the preparation of alkylaminotetrahydroindolizinones and tetralones was pr
A Metal–Organic Framework as a Multiphoton Excitation Regulator for the Activation of Inert C(sp3)?H Bonds and Oxygen
Cai, Junkai,Cai, Wei,Du, Zenggang,Duan, Chunying,He, Cheng,Ji, Guanfeng,Wei, Jianwei,Zhao, Liang
supporting information, (2021/11/27)
The activation and oxidization of inert C(sp3)?H bonds into value-added chemicals affords attractively economic and ecological benefits as well as central challenge in modern chemistry. Inspired by the natural enzymatic transformation, herein,
Minisci-Type Alkylation of N-Heteroarenes by N-(Acyloxy)phthalimide Esters Mediated by a Hantzsch Ester and Blue LED Light
Kyne, Sara Helen,Li, Jiacheng,Siang Tan, Suan,Wai Hong Chan, Philip
supporting information, (2022/01/11)
A synthetic method that enables the Hantzsch ester-mediated Minisci-type C2-alkylation of quinolines, isoquinolines and pyridines by N-(acyloxy)phthalimide esters (NHPI) under blue LED (light emitting diode) light (456 nm) is described. Achieved under mild reaction conditions at room temperature, the metal-free synthetic protocol was shown to be applicable to primary, secondary and tertiary NHPIs to give the alkylated N-heterocyclic products in yields of 21–99%. On introducing a chiral phosphoric acid, an asymmetric version of the reaction was also realised and provided product enantiomeric excess (ee) values of 53–99%. The reaction mechanism was delineated to involve excitation of an electron-donor acceptor (EDA) complex, formed from weak electrostatic interactions between the Hantzsch ester and NHPI, which generates the posited radical species of the redox active ester that undergoes addition to the N-heterocycle.
Direct functionalization of quinoxalin-2(1H)-one with alkanes: C(sp2)-H/C(sp3)-H cross coupling in transition metal-free mode
Dagar, Neha,Raha Roy, Sudipta,Singh, Swati
, p. 5383 - 5394 (2021/06/28)
Considering the significance of pharmaceutically important heterocycles, efficient and highly versatile protocols for the functionalization of diverse heterocycles with easily accessible feedstock are crucial. Here, we have reported selective alkylation of quinoxalin-2(1H)-one with a broad class of hydrocarbons having different C(sp3)-H bonds with varying bond strengths using di-tert-butyl peroxide (DTBP) as an alkoxyl radical mediator for hydrogen atom transfer (HAT). This dehydrogenative coupling approach utilizes feedstock chemicals such as cycloalkanes, cyclic ethers and alkyl arenes as coupling partners. This protocol exhibits good functional group compatibility and selectivity regarding both heterocycles and unactivated alkanes. Moreover, this methodology allows functionalization of relatively strong C-H bonds of adamantane and exclusive selectivity towards 3° C(sp3)-H bonds is observed. We also illustrate the applicability of this C(sp2)-H/C(sp3)-H cross-coupling for practical access to bioactive pharmaceuticals.
Photo-Induced Cross-Dehydrogenative Alkylation of Heteroarenes with Alkanes under Aerobic Conditions
Xu, Jun,Cai, Heng,Shen, Jiabin,Shen, Chao,Wu, Jie,Zhang, Pengfei,Liu, Xiaogang
, p. 17816 - 17832 (2021/12/17)
We report a Minisci-type cross-dehydrogenative alkylation in an aerobic atmosphere using abundant and inexpensive cerium chloride as a photocatalyst and air as an oxidant. This photoreaction exhibits excellent tolerance to functional groups and is suitabl
Modular Synthesis of Carbazole-Substituted Phthalimides as Potential Photocatalysts
F?ldesi, Tamás,Gonda, Zsombor,Nagy, Bálint,Novák, Zoltán
supporting information, (2021/11/22)
The modular synthesis of carbazole functionalized phthalimides (PIs) and their applicability as catalyst in selected photocatalytic transformations are reported. The developed synthetic approach provides high variability of phthalimide considering that the synthesis of the phthalimide core can be easily performed. Starting from fluorophthalic acid anhydrides, the corresponding fluorophthalimides were prepared with various amines, and the fluoro function ensured the introduction of carbazoles into the phthalimide framework through aromatic nucleophilic substitution. Besides the synthetic developments, some of the carbazolyl phthalimides were tested in four different photocatalytic transformations, which showed attractive and comparable activity to the known 4-CzIPN and noble metal complexes.
Development of a Quinolinium/Cobaloxime Dual Photocatalytic System for Oxidative C-C Cross-Couplings via H2Release
Li, Jianbin,Huang, Chia-Yu,Han, Jing-Tan,Li, Chao-Jun
, p. 14148 - 14158 (2021/11/27)
Designing molecular photocatalysts for potent photochemical reactivities ranks among the most challenging but rewarding endeavors in synthetic photochemistry. Herein, we document a quinoline-based organophotoredox catalyst, 2,4-bis(4-methoxyphenyl)quinoli
C-H alkylation of heteroarenes with alkyl oxalates by molecular photoelectrocatalysis
Xu, Fan,Lai, Xiao-Li,Xu, Hai-Chao
, p. 369 - 372 (2020/12/07)
An oxidant- and metal-free photoelectrocatalytic C-H alkylation reaction of heteroarenes with alkyl oxalates has been developed. Several classes of heteroaromatics, such as quinolines, isoquinolines, pyridines, and phenanthridines, can be alkylated with t
