931-49-7Relevant academic research and scientific papers
Metal-free cascade boron–heteroatom addition and alkylation with diazo compounds
Lv, Jiahang,Zhao, Binlin,Han, Ying,Yuan, Yu,Shi, Zhuangzhi
, p. 691 - 694 (2020/07/13)
Transition metal-catalyzed carbene transfer reaction is one of the most notable advances for C?C bond formation reactionsduring the past decade, which has been widely employed in the preparation of C3-substituted indoles. Here, we described an efficient e
Gold(I)-Catalyzed Oxidative 1,4-Additions of 3-En-1-ynamide with Nitrones via Carbon- versus Nitrogen-Addition Chemoselectivity
Tanpure, Sudhakar Dattatray,Kale, Balaji S.,Liu, Rai-Shung
supporting information, p. 1394 - 1399 (2021/02/20)
This work reports gold-catalyzed 1,4-oxofunctionalizations of 3-en-1-ynamides with nitrones, yielding two distinct E-configured products. We obtained 1,4-oxoarylation products from 3-en-1-ynamides bearing C(4)-electron-donating substituents and 1,4-oxoamination products from those analogues bearing C(4)-aryl substituents. We propose that if vinylgold carbenes are stable, imines undergo a para-arylation on these gold carbenes. If vinylgold carbenes are highly electron-deficient, this N-attack is irreversible to enable 1,4-oxoaminations.
Iron(II)-Based Metalloradical Activation: Switch from Traditional Click Chemistry to Denitrogenative Annulation
Roy, Satyajit,Khatua, Hillol,Das, Sandip Kumar,Chattopadhyay, Buddhadeb
, p. 11439 - 11443 (2019/07/17)
A unique concept for the intermolecular denitrogenative annulation of 1,2,3,4-tetrazoles and alkynes was discovered by using a catalytic amount of Fe(TPP)Cl and Zn dust. The reaction precludes the traditional, more favored click reaction between an organic azide and alkynes, and instead proceeds by an unprecedented metalloradical activation. The method is anticipated to advance access to the construction of important basic nitrogen heterocycles, which will in turn enable discoveries of new drug candidates.
BF3·OEt2-Promoted Propargyl Alcohol Rearrangement/[1,5]-Hydride Transfer/Cyclization Cascade Affording Tetrahydroquinolines
Zhao, Shuang,Wang, Xiaoyang,Wang, Pengfei,Wang, Guangwei,Zhao, Wentao,Tang, Xiangyang,Guo, Minjie
supporting information, p. 3990 - 3993 (2019/06/14)
An efficient BF3·OEt2-mediated propargyl alcohol rearrangement/[1,5]-hydride transfer/cyclization cascade for the synthesis of tetrahydroquinoline derivatives has been described. The substituents adjacent to triple bonds play an important role in the formation of ketones (via [1,3]-hydroxyl shift) or alkenyl fluorides which are products of formal trans-carbofluorination of internal alkynes. This method provides a rapid access to diverse heterocycles in moderate to excellent yields.
Boron Trichloride-Mediated Synthesis of Indoles via the Aminoboration of Alkynes
Lv, Jiahang,Zhao, Binlin,Liu, Li,Han, Ying,Yuan, Yu,Shi, Zhuangzhi
, p. 4054 - 4059 (2018/09/25)
We describe an efficient catalyst- and metal-free aminoboration of alkynes to 3-borylated indoles using one of the least expensive boron sources, BCl3. The major dichloro(indolyl)borane products can be used for the in situ construction of usefu
Accessing Polyoxygenated Dibenzofurans via the Union of Phenols and o-Benzoquinones: Rapid Syntheses of Metabolites Isolated from Ribes takare
Zhang, Meng Yao,Barrow, Russell A.
supporting information, p. 2302 - 2305 (2017/05/12)
The construction of polyoxygenated dibenzo[b,d]furan frameworks from the union of substituted phenols/naphthols and o-benzoquinones via a Michael-oxidation-oxa-Michael cascade is reported. The power of this transformation is demonstrated in the generation of a library of highly substituted dibenzofurans, featuring specifically substituted molecules containing broad ranges of functionality. The utility of this method is showcased in the total syntheses of two dibenzofurans isolated from Ribes takare, assembling the carbon scaffold of both natural products in one operation.
Synthesis, structural, catecholase, tyrosinase and DFT studies of pyrazoloquinoxaline derivatives
Bouanane, Zohra,Bounekhel, Mahmoud,Elkolli, Meriem,Abrigach, Farid,Khoutoul, Mohamed,Bouyala, Rabab,Touzani, Rachid,Hellal, Abdelkader
, p. 238 - 246 (2017/03/22)
Six functional multidentate ligands: 2,3-bis(3,5-dimethyl-1H-pyrazol-1-yl) quinoxaline, L1, 2,3-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-nitroquinoxaline, L2, 2,3-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-methylquinoxaline, L3, 2-(3,5-dimethyl-1H-pyrazol-1-yl)-3-hydrazinyl-6-nitroquinoxaline L4, 2-chloro-3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-methylquinoxaline, L5, 2-chloro-3-(3,5-dimethyl-1H-pyrazol-1-yl) quinoxaline, L6, and a new copper (II) complex, were prepared and evaluated for their catecholase activities at aerobic conditions. We found that, the reaction rate depends on: The nature of the substituents in the quinoxaline ring, counter anion, metal, concentration of ligand and the used solvent. The complex obtained in-situ from reaction of one equivalent of ligand L1 and two equivalents of Cu(CH3COO)2 in methanol showed the highest oxidation rate activity (V?=?33.48?μmol?L?1. min?1). In addition, geometry optimizations of the complexes in order to get better insight into the geometry and the electronic structure and chemical reactivity were carried out by means of DFT calculations.
Palladium-catalyzed difunctionalization of internal alkynes via highly regioselective 6- endo cyclization and alkenylation of enynoates: Synthesis of multisubstituted pyrones
Tian, Pan-Pan,Cai, Sai-Hu,Liang, Qiu-Ju,Zhou, Xing-Yi,Xu, Yun-He,Loh, Teck-Peng
, p. 1636 - 1639 (2015/04/14)
An efficient Pd(II)-catalyzed difunctionalization reaction of internal alkynes is reported. In this reaction, various enynoates and electron-deficient alkenes were used for the syntheses of useful highly substituted pyrone derivatives via a 6-endo cycliza
ZnII- and AuI-catalyzed regioselective hydrative oxidations of 3-En-1-ynes with selectfluor: Realization of 1,4-dioxo and 1,4-oxohydroxy functionalizations
Jadhav, Appaso Mahadev,Gawade, Sagar Ashok,Vasu, Dhananjayan,Dateer, Ramesh B.,Liu, Rai-Shung
, p. 1813 - 1817 (2014/03/21)
Catalytic 1,4-dioxo functionalizations of 3-en-1-ynes to (Z)- and (E)-2-en-1,4-dicarbonyl compounds are described. This regioselective difunctionalization was achieved in one-pot operation through initial alkyne hydration followed by in situ Selectfluor oxidation. The presence of pyridine alters the reaction chemoselectivity to give 4-hydroxy-2-en-1-carbonyl products instead. A cooperative action of pyridine and ZnII assists the hydrolysis of key oxonium intermediate.
