scholarly journals Atom-Economic Synthesis of 4-Pyrones from Diynones and Water

2017 ◽  
Author(s):  
Yan-Li Xu ◽  
Qing-Hu Teng ◽  
Wei Tong ◽  
Heng-Shan Wang ◽  
Ying-Ming Pan ◽  
...  
Keyword(s):  
Transition Metal ◽  
Nucleophilic Addition ◽  
Environmentally Benign ◽  
Metal Free ◽  
Efficient Access ◽  
Simple Atom

Transition-metal-free synthesis of 4-pyrones via TfOH-promoted nucleophilic addition/cyclization of diynones and water has been developed. This transformation is simple, atom economical and environmentally benign, providing rapid and efficient access to substituted 4-pyrones.

Transition-Metal-Free, Intermolecular Azidoheteroarylation of Alkenes: Efficient Access to β-Azidoalkylated Quinoxalinones and Preliminary Antifungal Evaluation Against Magnaporthe grisea

Synthesis ◽  
2020 ◽  
Vol 52 (16) ◽  
pp. 2395-2409
Author(s):  
Weiwei Qin ◽  
Zhaodong Li ◽  
Yiming Du ◽  
Yue Chen ◽  
Yun-Lin Liu
Keyword(s):  
Transition Metal ◽  
Magnaporthe Grisea ◽  
Single Step ◽  
Domino Reaction ◽  
Efficient Synthesis ◽  
Metal Free ◽  
Efficient Access ◽  
First Time ◽  
Antibacterial Evaluation ◽  
Addition Pathway

An efficient, PhI(OAc)2-mediated, radical azidoheteroarylation of alkenes under transition-metal-free conditions is reported by employing TMSN3 and quinoxalin-2(1H)-ones as coupling partners. This domino reaction allows an efficient synthesis of valuable orangoazides containing quinoxalin-2(1H)-one derivatives and could be extended to phosphinyl-alkylated quinoxalin-2(1H)-one in a single step in moderate to excellent yields under mild conditions, as demonstrated by the preliminary antibacterial evaluation against Magnaporthe grisea for the first time. Mechanistic studies revealed that this transformation undergoes a cascade addition pathway controlled by a polar radical.

Transition-metal-free and organic solvent-free conversion of N-substituted 2-aminobiaryls into corresponding carbazoles via intramolecular oxidative radical cyclization induced by peroxodisulfate

2017 ◽  
Vol 19 (24) ◽  
pp. 5854-5861 ◽  
Author(s):  
Palani Natarajan ◽  
Priya Priya ◽  
Deachen Chuskit
Keyword(s):  
Transition Metal ◽  
Organic Solvent ◽  
Radical Cyclization ◽  
Solvent Free ◽  
Environmentally Benign ◽  
Metal Free ◽  
Benign Synthesis ◽  
Oxidative Radical Cyclization

An atom-economical and environmentally benign synthesis of N-substituted carbazoles is described. This methodology afforded products in 90–120 minutes.

scholarly journals Transition-Metal-Free [3+2] Dehydration Cycloaddition of Donor-Acceptor Cyclopropanes With 2-Naphthols

2021 ◽  
Vol 9 ◽  
Author(s):  
Hua Zhao ◽  
Peng Shen ◽  
Dongru Sun ◽  
Hongbin Zhai ◽  
Yufen Zhao
Keyword(s):  
Transition Metal ◽  
Ring Opening ◽  
Metal Catalysts ◽  
Transition Metal Catalysts ◽  
Cyclization Reaction ◽  
Metal Free ◽  
Efficient Access ◽  
Donor Acceptor ◽  
Acid Catalyzed ◽  
Synthetic Application

A Brønsted acid-catalyzed domino ring-opening cyclization transformation of donor-acceptor (D-A) cyclopropanes and 2-naphthols has been developed. This formal [3+2] cyclization reaction provided novel and efficient access to the naphthalene-fused cyclopentanes in the absence of any transition-metal catalysts or additives. This robust procedure was completed smoothly on a gram-scale to afford the corresponding product with comparable efficiency. Furthermore, the synthetic application of the prepared product has been demonstrated by its transformation into a variety of synthetically useful molecules.

Transition metal-free access to 3,4-dihydro-1,2-oxaphosphinine-2-oxides from phosphonochloridates and chalcones through tandem Michael addition and nucleophilic substitution

2019 ◽  
Vol 55 (87) ◽  
pp. 13124-13127 ◽  
Author(s):  
Zhicheng Fu ◽  
Simin Sun ◽  
Anjian Yang ◽  
Fang Sun ◽  
Jiaxi Xu
Keyword(s):  
Transition Metal ◽  
Nucleophilic Substitution ◽  
Michael Addition ◽  
Nucleophilic Addition ◽  
Free Access ◽  
Metal Free

3,4-Dihydro-1,2-oxaphosphinine 2-oxides are synthesized through tandem intermolecular nucleophilic addition and cyclization of phosphonochloridates and enones in the presence of base.

scholarly journals A cascade double 1,4-addition/intramolecular annulation strategy for expeditious assembly of unsymmetrical dibenzofurans

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Xinwei He ◽  
Ruxue Li ◽  
Pui Ying Choy ◽  
Mengqing Xie ◽  
Jiahui Duan ◽  
...  
Keyword(s):  
Transition Metal ◽  
Late Stage ◽  
Functional Group ◽  
Conjugate Addition ◽  
Carbon Structure ◽  
Metal Free ◽  
Air Atmosphere ◽  
Efficient Access ◽  
Synthetic Routes ◽  
Metal Catalyzed

AbstractExisting synthetic routes for accessing dibenzofuran core have intrinsic regioselectivity, limiting the substitution patterns available in heteropolycyclic arene products. Here we report a double 1,4-conjugate addition/intramolecular annulation cascade reaction between propargylamines and two equivalents of imidazolium methylides that allows efficient access of structurally versatile dibenzofurans. This transition metal-free protocol proceeds smoothly under bench-top air atmosphere and offers easy manipulation of substituents on the dibenzofuran core, and also provides good-to-excellent product yields with good functional group tolerance, particularly the –Br and –Cl groups which are often incompatible with existing metal-catalyzed C–C and/or C–O bond ring-forming processes. It is worth noting that ladder-type π-systems with all-arene quarternary carbon structure can be straightforwardly generated upon simple late-stage functionalization.

A metal-free method for facile synthesis of indanones via intramolecular hydroacylation of 2-vinylbenzaldehydes

2021 ◽  
Author(s):  
Guoxue He ◽  
Jinyu Ma ◽  
Jianhui Zhou ◽  
Chunpu Li ◽  
Hong Liu ◽  
...  
Keyword(s):  
Transition Metal ◽  
Environmentally Benign ◽  
Facile Synthesis ◽  
Metal Free ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed

A facile method access to indanones was developed under metal- and additive-free conditions in which L-proline served as efficient and environmentally benign catalysts. Compared with previous indanones synthesis by transition-metal-catalyzed...

2-Pyridinylmethyl Borrowing: Base-promoted C-Alkylation of (Pyridin-2-yl)methyl Alcohols with Ketones via Cleavage of Unstrained C(sp3)–C(sp3) Bonds

2021 ◽  
Author(s):  
Chuan-Ming Hong ◽  
Fei-Fei Zou ◽  
Xin Zhuang ◽  
Zhen Luo ◽  
Zheng-Qiang Liu ◽  
...  
Keyword(s):  
Transition Metal ◽  
Environmentally Benign ◽  
Methyl Ketones ◽  
Metal Free

A transition-metal-free synthesis of β-(pyridin-2-yl)-methyl ketones, utilizing (pyridin-2-yl)methyl alcohols and ketones through 2-pyridinylmethyl borrowing strategy, has been disclosed. This approach provides an efficient, available and environmentally benign access, leading to...

Transition metal-free C-3 functionalization of quinoxalin-2(1H)-ones: recent advances and sanguine future

2021 ◽  
Author(s):  
Kiran ◽  
Payal Rani ◽  
Sandhya Chahal ◽  
Jayant Sindhu ◽  
Sudhir Kumar ◽  
...  
Keyword(s):  
Transition Metal ◽  
Environmentally Benign ◽  
Metal Free ◽  
Gradual Shift ◽  
Recent Advances ◽  
Metal Catalyzed

A gradual shift from metal-catalyzed to metal-free methods is occurring, as the latter are more environmentally benign. This review discusses sustainable protocols for the construction of C–C, C–N, C–P, C–S, and C–O bonds via C–H functionalization of quinoxalin-2(1H)-ones.

Transition-Metal-Free One-Pot Tandem Synthesis of 4-Quinolone and 4H-Thiochromen-4-one Derivatives Through Sequential Nucleophilic Addition–Elimination–SNAr Reaction

Synthesis ◽  
2017 ◽  
Vol 49 (18) ◽  
pp. 4309-4320 ◽  
Author(s):  
Jinsong Peng ◽  
Chunxia Chen ◽  
Deqiang Wang ◽  
Peng Sun ◽  
Peiyun Jia ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Transition Metal ◽  
Nucleophilic Addition ◽  
One Pot ◽  
Metal Free ◽  
Chlorine Anion ◽  
Sodium Hydrogen ◽  
Snar Reaction ◽  
Tandem Synthesis

4-Quinolone and 4H-thiochromen-4-one derivatives are readily synthesized in a tandem one-pot manner in good to excellent yields. Starting from (Z)-β-chlorovinyl ketones, an intermolecular nucleo­philic addition of amines or sodium hydrogen sulfide to (Z)-β-chloro­vinyl ketones was followed by elimination of chlorine anion to give Z-enamine or thioenol intermediates, which can be transformed to 4-quinolone or 4H-thiochromen-4-one products through intramolecular SNAr reaction, respectively.

Sign in / Sign up

Export Citation Format

Share Document