39833-45-9Relevant academic research and scientific papers
Remarkable reactivity enhancement with Sb?N inter-coordination of ethynyl-1,5-azastibocines in Pd-catalyzed cross-coupling reactions with organic halides
Kakusawa, Naoki,Tobiyasu, Yoshinori,Yasuike, Shuji,Yamaguchi, Kentaro,Seki, Hiroko,Kurita, Jyoji
, p. 8589 - 8592 (2003)
The reaction of 12-arylethynyl-6-methyl-5,6,7,12-tetrahydrodibenzo[c,f][1, 5]-azastibocines with organic halides such as acyl halides and aryl halides in the presence of PdCl2(PPh3)2 as a catalyst led to the formation of cross-coupling products, alkynyl ketones and diaryl acetylenes, in good yields. The reactivity of the ethynyl group on the 1,5-azastibocines was far superior to that on diphenyl(phenylethynyl)stibane, which brought about marked improvement in the reaction conditions (lower temperature and shorter reaction time) and in the yields of the cross-coupling products. Single-crystal X-ray analysis of the ethynyl-1,5-azastibocine showed the presence of intramolecular Sb?N interaction which should be responsible for the remarkable reactivity enhancement of the 1,5-azastibocines for this type of reaction.
Organoborane-catalyzed selective 1,2-reduction of alkynones with hydride transfer: Synthesis of benzyl alkynes
Zhai, Lele,Yang, Zhigang,Man, Qinghong,Yang, Mingyu,Ren, Yangqing,Wang, Lei,Li, Huilin,She, Xuegong
, (2022/01/28)
Benzyl alkynes are important organic building blocks in organic synthesis. We report herein a B(C6F5)3-catalyzed site-selective 1,2-reduction of readily available alkynones to access benzyl alkyne derivatives. Under the de
Synthesis of Isoselenazoles and Isothiazoles from Demethoxylative Cycloaddition of Alkynyl Oxime Ethers
Zhang, Zhu-Zhu,Chen, Rong,Zhang, Xiao-Hong,Zhang, Xing-Guo
, p. 632 - 642 (2020/12/22)
A general method for the synthesis of isoselenazoles and isothiazoles has been developed by the base-promoted demethoxylative cycloaddition of alkynyl oxime ethers using the cheap and inactive Se powder and Na2S as selenium and sulfur sources. This transformation features the direct construction of N-, Se-, and S-containing heterocycles through the formation of N-Se/S and C-Se/S bonds in one-pot reactions with excellent functional group tolerance.
Base-Promoted Synthesis of Polysubstituted 4-Aminoquinolines from Ynones and 2-Aminobenzonitriles under Transition-Metal-Free Conditions
Kumar, Ankit,Mishra, Pawan K.,Saini, Kapil Mohan,Verma, Akhilesh K.
supporting information, p. 2546 - 2551 (2021/03/16)
A transition-metal-free and base-promoted one-pot reaction of ynones with 2-aminobenzonitriles is described. The reaction was initiated through sequential aza-Michael addition/intramolecular annulation to afford various multisubstituted 4-aminoquinolines
Methylation Alkynylation of Terminal Alkenes via 1,2-Alkynyl Migration Using Dicumyl Peroxide as the Methyl Source
Qin, Yi-Qun,Chen, De,Liu, Liang,Zhang, Jia-Jia,Peng, Xin-Ju,Luo, Yong-Yue,Deng, Wei,Xiang, Jiannan
, p. 4700 - 4708 (2021/08/31)
The metal-free oxidative alkene methylation/alkynylation of 1,4-enyn-3-ols with an organic peroxide as the methyl source has been developed, which provides straightforward and practical access to the challenging quaternary-carbon-containing but-3-yn-1-one
Feeding Carbonylation with CO2via the Synergy of Single-Site/Nanocluster Catalysts in a Photosensitizing MOF
Fu, Shanshan,Guo, Guang-Chen,Guo, Song,Lu, Tong-Bu,Yao, Shuang,Yuan, Wenjuan,Zhang, Zhi-Ming
, p. 20792 - 20801 (2021/12/14)
Solar-driven carbonylation with CO2 replacing toxic CO as a C1 source is of considerable interest; however it remains a great challenge due to the inert CO2 molecule. Herein, we integrate cobalt single-site and ultrafine CuPd nanocluster catalysts into a
Electrochemical Palladium-Catalyzed Oxidative Sonogashira Carbonylation of Arylhydrazines and Alkynes to Ynones
Cao, Yue,Hu, Jingcheng,Lei, Aiwen,Li, Haoran,Shi, Renyi,Wu, Yong,Xu, Minghao,Yi, Hong,Zeng, Li
supporting information, p. 12460 - 12466 (2021/08/24)
Oxidative carbonylation using carbon monoxide has evolved as an attractive tool to valuable carbonyl-containing compounds, while mixing CO with a stoichiometric amount of a chemical oxidant especially oxygen is hazardous and limits its application in scale-up synthesis. By employing anodic oxidation, we developed an electrochemical palladium-catalyzed oxidative carbonylation of arylhydrazines with alkynes, which is regarded as an alternative supplement of the carbonylative Sonogashira reaction. Combining an undivided cell with constant current mode, oxygen-free conditions avoids the explosion hazard of CO. A diversity of ynones are efficiently obtained using accessible arylhydrazines and alkynes under copper-free conditions. A possible mechanism of the electrochemical Pd(0)/Pd(II) cycle is rationalized based upon cyclic voltammetry, kinetic studies, and intermediates experiments.
Ynonylation of Acyl Radicals by Electroinduced Homolysis of 4-Acyl-1,4-dihydropyridines
Luo, Xiaosheng,Wang, Ping
supporting information, p. 4960 - 4965 (2021/07/20)
Herein we report the conversion of 4-Acyl-1,4-dihydropyridines (DHPs) into ynones under electrochemical conditions. The reaction proceeds via the homolysis of acyl-DHP under electron activation. The resulting acyl radicals react with hypervalent iodine(III) reagents to form the target ynones or ynamides in acceptable yields. This mild reaction condition allows wider functionality tolerance that includes halides, carboxylates, or alkenes. The synthetic utility of this methodology is further demonstrated by the late-stage modification of complex molecules.
One-Pot Palladium-Catalyzed Carbonylative Sonogashira Coupling using Carbon Dioxide as Carbonyl Source
Xiong, Wenfang,Wu, Bowen,Zhu, Baiyao,Tan, Xiaobin,Wang, Lu,Wu, Wanqing,Qi, Chaorong,Jiang, Huanfeng
, p. 2843 - 2851 (2021/05/10)
Carbonylation coupling reaction has emerged as a powerful and versatile strategy for the construction of carbonyl-containing compounds in modern synthetic chemistry over the past years. Carbon dioxide, a renewable one carbon molecule, has become one of the most attractive and promising alternative carbonyl sources due to its highly abundance, nontoxicity and stability in comparison with CO in recent years. However, in most cases, a two-chamber technique was generally necessary to allow the CO-producing and CO-consuming processes to perform successfully because of the complexities and incompatibility of reaction conditions, when carbon dioxide was utilized as carbonyl source. Herein, a practical one-pot protocol using carbon dioxide as the carbonyl source for the palladium-catalyzed carbonylative Sonogashira coupling has been established, providing an expedient and practical route to a wide range of functionalized alkynones and indoxyls under mild reaction conditions. By finding a suitable catalytic system, the method allowed the CO-generating and CO-consuming processes to proceed in one pot, wherein carbon monoxide was generated in situ from the reduction of carbon dioxide in the absence of any fluoride reagents. Simple and safe operation, readily available substrates, good functional group tolerance and mild reaction conditions are the features of the method.
Straightforward Stereoselective Synthesis of Seven-Membered Oxa-Bridged Rings through in Situ Generated Cycloheptenol Derivatives
Wang, Mengdan,Yin, Liqiang,Cheng, Lu,Yang, Yajie,Li, Yanzhong
, p. 12956 - 12963 (2021/09/13)
An iodine-mediated stereoselective synthesis of seven-membered oxa-bridged rings via in situ generated cycloheptenols was reported. This process was realized through the combination of C-C σ-bond cleavage and C-O bond-forming reactions in a one-pot fashion from simple and easily accessible raw materials. The formation of carbon radicals initiated by I2 was the key to the reaction.
