127388-13-0Relevant academic research and scientific papers
One-pot activation-alkynylation-cyclization synthesis of 1,5-diacyl-5-hydroxypyrazolines in a consecutive three-component fashion
G?rgen, Christina,Boden, Katharina,Reiss, Guido J.,Frank, Walter,Müller, Thomas J.J.
, p. 1360 - 1370 (2019)
A consecutive three-component activation-alkynylation-cyclization reaction of (hetero)aryl glyoxylic acids, oxalyl chloride, arylacetylenes, and hydrazides efficiently forms 1,5-diacyl-5-hydroxypyrazolines in moderate to good yields. The structures were unambiguously corroborated by comprehensive NMR spectroscopy and X-ray structure analyses of selected derivatives.
Copper-catalyzed aerobic oxidative coupling of terminal alkynes with α-carbonyl aldehydes: An expedient approach toward ynediones
Zhou, Bochao,Guo, Shiyu,Fang, Zheng,Yang, Zhao,Guo, Kai
, (2019)
An efficient and mild one-pot approach for copper-catalyzed aerobic oxidative coupling of α-carbonyl aldehydes with terminal alkynes toward ynediones has been developed. Moreover, a variety of ynediones were constructed under the optimized reaction condit
Visible light-induced aerobic oxidation of diarylalkynes to α-diketones catalyzed by copper-superoxo at room temperature
Charpe, Vaibhav Pramod,Hwang, Kuo Chu,Sagadevan, Arunachalam
supporting information, p. 4426 - 4432 (2020/08/10)
We have developed the visible light induced simple copper(ii) chloride catalyzed oxidation of diarylacetylenes to α-diketones by molecular oxygen at room temperature. The in situ generated copper(ii)-superoxo complex is a light-absorbing species that oxidizes inert diarylacetylenes to α-diketones. In contrast to reported photochemical processes, the current oxidation protocol does not require any exogenous photocatalyst or radical initiator. The green chemistry metrics evaluation signifies that the E-factor for the current oxidation process is ～2.3 times better than that of reported photochemical processes. The current reaction scores 63 on the EcoScale of 0-100, indicating an adequate synthesis process. Thus, the overall oxidation process is simple, environmentally benign, and economically feasible. This journal is
(Ar-tpy)RuII(ACN)3: A Water-Soluble Catalyst for Aldehyde Amidation, Olefin Oxo-Scissoring, and Alkyne Oxygenation
Joarder, Dripta De,Gayen, Subrata,Sarkar, Rajarshi,Bhattacharya, Rajarshi,Roy, Sima,Maiti, Dilip K.
, p. 8468 - 8480 (2019/07/03)
The synthetic chemists always look for developing new catalysts, sustainable catalysis, and their applications in various organic transformations. Herein, we report a new class of water-soluble complexes, (Ar-tpy)RuII(ACN)3, utilizing designed terpyridines possessing electron-donating and -withdrawing aromatic residues for tuning the catalytic activity of the Ru(II) complex. These complexes displayed excellent catalytic activity for several oxidative organic transformations including late-stage C-H functionalization of aldehydes with NH2OR to valuable primary amides in nonconventional aqueous media with excellent yield. Its diverse catalytic power was established for direct oxo-scissoring of a wide range of alkenes to furnish aldehydes and/or ketones in high yield using a low catalyst loading in the water. Its smart catalytic activity under mild conditions was validated for dioxygenation of alkynes to highly demanding labile synthons, 1,2-diketones, and/or acids. This general and sustainable catalysis was successfully employed on sugar-based substrates to obtain the chiral amides, aldehydes, and labile 1,2-diketones. The catalyst is recovered and reused with a moderate turnover. The proposed mechanistic pathway is supported by isolation of the intermediates and their characterization. This multifaceted sustainable catalysis is a unique tool, especially for late-stage functionalization, to furnish the targeted compounds through frequently used amidation and oxygenation processes in the academia and industry.
Electrochemical synthesis of 1,2-diketones from alkynes under transition-metal-catalyst-free conditions
Zhou, Jie,Tao, Xiang-Zhang,Dai, Jian-Jun,Li, Chen-Guang,Xu, Jun,Xu, Hong-Mei,Xu, Hua-Jian
supporting information, p. 9208 - 9211 (2019/08/07)
We report an electrochemical protocol for the direct oxidation of internal alkynes in air to provide 1,2-diketones. A variety of functional groups and heterocycle-containing substrates can be tolerated well under mild conditions.
N-Heterocyclic Carbene-Catalyzed Umpolung of Alkynyl 1,2-Diketones
Kong, Xiangwen,Zhang, Guoxiang,Yang, Shuang,Liu, Xiaozhi,Fang, Xinqiang
, p. 2729 - 2734 (2017/08/23)
The umpolung of alkynyl 1,2-diketones via N-heterocyclic carbene (NHC) catalysis was achieved for the first time, allowing the rapid access to a large variety of synthetically and pharmaceutically important α-pyrones under very mild conditions. A completely new NHC-catalyzed umpolung pattern involving an O-acylated allenolate as the key intermediate was proposed. Moreover, an unprecedented reaction pathway, featured by a series of group migrations and new bond formation, was postulated to demonstrate the formation of the products. (Figure presented.).
Synthesis of 1,2-Diketones via a Metal-Free, Visible-Light-Induced Aerobic Photooxidation of Alkynes
Liu, Xu,Cong, Tiantian,Liu, Ping,Sun, Peipei
, p. 7256 - 7261 (2016/08/30)
1,2-Diketones were synthesized by the oxidation of corresponding alkynes using air as the oxidant under metal-free conditions upon irradiation of blue light. A cheap and readily available organic dye, eosin Y, was used as the photocatalyst. For various substituents on the aryl ring, the reaction proceeded smoothly to give the dicarbonylation products in moderate to good yields. Some oxidation-sensitive groups, such as formyl and the carbon-carbon double bond, were tolerated under the developed reaction conditions.
PPh3·HBr-DMSO: A Reagent System for Diverse Chemoselective Transformations
Mal, Kanchan,Kaur, Amanpreet,Haque, Fazle,Das, Indrajit
, p. 6400 - 6410 (2015/06/30)
The broad applicability of the hitherto unexplored reagent combination PPh3·HBr-DMSO is exemplified with multiple highly diverse one-step transformations to synthetically useful building blocks, such as flavones, 4H-thiochromen-4-ones, α-hydroxy ketones, 1,4-naphthoquinones (including vitamin K3), 2-bromo-3-substituted-1H-1-indenones, 2-methylthio-1H-1-indenones, 3-butyne-1,2-dione, and 4-pentene-2,3-diones. The simple and mild reaction conditions make the reagent superior in terms of yield and substrate scope in comparison with the existing alternatives.
Oxidative coupling of terminal alkyne with α-hydroxy ketone: An expedient approach toward ynediones
Zhang, Zeguang,Jiang, Xuefeng
supporting information, p. 4400 - 4403 (2015/02/18)
An efficient and mild copper-catalyzed one-pot approach toward ynediones has been established. A variety of ynediones were constructed directly through oxidative coupling of alkyne with α-hydroxy ketone. Oxygen-oxidizing and neutral conditions in one-pot for a wide range of substrates including natural product derivatives make this transformation highly efficient and practical. On the basis of control experiments, in situ IR measurements, and isotopic labeling experiments, a plausible mechanism involving intermediate phenylglyoxal was drawn. Applications by synthesis of various heterocycles were also investigated.
Catalytic syntheses of N-heterocyclic ynones and ynediones by in situ activation of carboxylic acids with oxalyl chloride
Boersch, Christina,Merkul, Eugen,Mueller, Thomas J. J.
, p. 10448 - 10452 (2011/12/05)
Breaking the bottleneck: α-Keto carboxylic acids and N-heterocyclic carboxylic acids are activated in situ with oxalyl chloride then catalytically alkynylated to give ynediones and N-heterocyclic ynones efficiently in a one-pot fashion. 5-Acylpyrazoles and 2-phenylaminopyrimidines, potentially interesting for pharmaceutical applications, are readily synthesized in concise one-pot, three-component syntheses. Copyright
