1538551-54-0Relevant articles and documents
Minisci-Type Alkylation of N-Heteroarenes by N-(Acyloxy)phthalimide Esters Mediated by a Hantzsch Ester and Blue LED Light
Li, Jiacheng,Siang Tan, Suan,Kyne, Sara Helen,Wai Hong Chan, Philip
supporting information, p. 802 - 810 (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.
An organophotoredox-catalyzed redox-neutral cascade involving: N -(acyloxy)phthalimides and allenamides: Synthesis of indoles
Das, Sanju,Azim, Aznur,Hota, Sudhir Kumar,Panda, Satya Prakash,Murarka, Sandip,De Sarkar, Suman
supporting information, p. 13130 - 13133 (2021/12/16)
An organophotoredox-catalyzed radical cascade of allenamides and alkyl N-(acyloxy)phthalimides for the synthesis of indoles is documented. The method features mild and robust reaction conditions, and exhibits broad scope. The tandem process enriches the l
Visible-Light-Triggered Decarboxylative Alkylation of 8-Acylaminoquinoline with N -Hydroxyphthalimide Ester
Aisha, Aertuke,Jin, Can,Li, Deyu,Sun, Bin,Zhu, Rui,Zhuang, Xiaohui
supporting information, p. 677 - 682 (2020/04/08)
A facile protocol for visible-light-induced decarboxylative radical coupling of NHP esters with 8-aminoquinoline amides is reported, affording a highly efficient approach to synthesize a variety of 2-alkylated or 2,4-dialkylated 8-aminoquinoline derivativ
Metal-Free Regioselective Alkylation of Imidazo[1,2- a ]pyridines with N -Hydroxyphthalimide Esters under Organic Photoredox Catalysis
Jin, Can,Sun, Bin,Xu, Min,Xu, Tengwei,Yang, Jin,Zhang, Liang,Zhu, Rui
supporting information, p. 363 - 368 (2020/02/27)
A visible-light-induced direct C-H alkylation of imidazo[1,2- a ]pyridines has been developed. It proceeds at room temperature by employing inexpensive Eosin Y as a photocatalyst and alkyl N -hydroxyphthalimide (NHP) esters as alkylation reagents. A varie
Photochemical Decarboxylative C(sp3)-X Coupling Facilitated by Weak Interaction of N-Heterocyclic Carbene
Chen, Kun-Quan,Wang, Zhi-Xiang,Chen, Xiang-Yu
supporting information, p. 8059 - 8064 (2020/11/02)
While N-hydroxyphthalimide (NHPI) ester has emerged as a powerful reagent as an alkyl radical source for a variety of C-C bond formations, the corresponding C(sp3)-N bond formation is still in its infancy. We demonstrate herein transition-metal-free decarboxylative C(sp3)-X bond formation enabled by the photochemical activity of the NHPI ester-NaI-NHC complex, giving primary C(sp3)-(N)phth, secondary C(sp3)-I, or tertiary C(sp3)-(meta C)phth coupling products. The primary C(sp3)-(N)phth coupling offers convenient access to primary amines.
N-Doped Yellow TiO2 Hollow Sphere-Mediated Visible-Light-Driven Efficient Esterification of Alcohol and N-Hydroxyimides to Active Esters
Singha, Krishnadipti,Ghosh, Subhash Ch.,Panda, Asit Baran
, p. 3205 - 3212 (2019/09/09)
Herein we report a simple synthetic protocol for N-doped yellow TiO2 (N-TiO2) hollow spheres as an efficient visible-light-active photocatalyst using aqueous titanium peroxocarbonate complex (TPCC) solution as precursor and NH4OH. In the developed strategy, the ammonium ion of TPCC and NH4OH acts as nitrogen source and structure-directing agent. The synthesized N-TiO2 hollow spheres are capable of promoting the synthesis of active esters of N-hydroxyimide and alcohol through simultaneous selective oxidation of alcohol to aldehyde followed by cross-dehydrogenative coupling (CDC) under ambient conditions upon irradiation of visible light. It is possible to develop a novel and cost-effective one-pot strategy for the synthesis of important esters and amides on gram scale using the developed strategy. The catalytic activity of N-TiO2 hollow spheres is much superior to that of other reported N-TiO2 samples as well as TiO2 with varying morphology.
Ni-Catalyzed β-Alkylation of Cyclopropanol-Derived Homoenolates
Mills, L. Reginald,Zhou, Cuihan,Fung, Emily,Rousseaux, Sophie A. L.
supporting information, p. 8805 - 8809 (2019/11/03)
Metal homoenolates are valuable synthetic intermediates which provide access to β-functionalized ketones. In this report, we disclose a Ni-catalyzed β-alkylation reaction of cyclopropanol-derived homoenolates using redox-active N-hydroxyphthalimide (NHPI) esters as the alkylating reagents. The reaction is compatible with 1°, 2°, and 3° NHPI esters. Mechanistic studies imply radical activation of the NHPI ester and 2e β-carbon elimination occurring on the cyclopropanol.
Photoredox Decarboxylative C(sp3)-N Coupling of α-Diazoacetates with Alkyl N-Hydroxyphthalimide Esters for Diversified Synthesis of Functionalized N-Alkyl Hydrazones
Chan, Chun-Ming,Xing, Qi,Chow, Yip-Chi,Hung, Sing-Fung,Yu, Wing-Yiu
supporting information, p. 8037 - 8043 (2019/10/11)
Herein we report a metal-free photocatalytic coupling reaction for the synthesis of structurally and functionally diverse N-alkyl hydrazones from α-diazoacetates and N-alkyl hydroxyphthalimide esters. By employing Rose Bengal as a photocatalyst with yellow LEDs irradiation, over 60 N-alkyl hydrazones were synthesized. Fluorescence quenching analysis and deuterium incorporation experiments reveal that Hantzsch ester serves as both an electron donor and proton source for the reaction. This strategy offers a simple retrosynthetic disconnection for conventionally inaccessible C(sp3)-rich N-alkyl hydrazones.
Visible-light-induced regioselective alkylation of coumarins via decarboxylative coupling with N-hydroxyphthalimide esters
Jin, Can,Yan, Zhiyang,Sun, Bin,Yang, Jin
supporting information, p. 2064 - 2068 (2019/04/11)
An efficient photocatalytic decarboxylative 3-position alkylation of coumarins by using alkyl N-hydroxyphthalimide esters as alkylation reagents has been developed. A variety of NHP esters derived from aliphatic carboxylic acids (primary, secondary, and tertiary) has been proved to be tolerated for this decarboxylation process, affording a broad scope of 3-alkylated coumarin derivatives in moderate to excellent yields. This protocol was highlighted by its mild conditions, readily available starting materials, operational simplicity, and wide functional group tolerance.
Construction of C(sp2)?C(sp3) Bond between Quinoxalin-2(1H)-ones and N-Hydroxyphthalimide Esters via Photocatalytic Decarboxylative Coupling
Yan, Zhiyang,Sun, Bin,Zhang, Xun,Zhuang, Xiaohui,Yang, Jin,Su, Weike,Jin, Can
, p. 3344 - 3349 (2019/09/06)
A novel visible-light-driven decarboxylative coupling of alkyl N-hydroxyphthalimide esters (NHP esters) with quinoxalin-2(1H)-ones has been developed. This C(sp2)?C(sp3) bond-forming transformation exhibits excellent substrate generality with respect to both the coupling partners. Of note, a series of 3-primary alkyl-substituted quinoxalin-2(1H)-ones that were difficult to synthesize by previous methods could be obtained in moderate to excellent yields. Additionally, the mild conditions, easy availability of substrates, wide functional group tolerance and operational simplicity make this protocol practical in the synthesis of 3-alkylated quinoxalin-2(1H)-ones.
