157670-38-7Relevant academic research and scientific papers
Probing the arenium-ion (ProtonTransfer) versus the cation-radical (Electron Transfer) mechanism of scholl reaction using DDQ as oxidant
Zhai, Linyi,Shukla, Ruchi,Wadumethrige, Shriya H.,Rathore, Rajendra
, p. 4748 - 4760 (2010)
(Figure Presented) DDQ/H+ system readily oxidizes a variety of electron donors with oxidation potential as high as ～1.7 V to the corresponding cation radicals. A re-examination of the controversial arenium-ion versus cation-radical mechanisms for Scholl reaction using DDQ/H+ together with commonly utilized FeCl3 as oxidants led us to demonstrate that the reaction proceeds largely via a cation-radical mechanism. The critical experimental evidence in support of a cation-radical pathway for the Scholl reaction includes the following: (i) There is no reaction in Scholl precursors in a mixture of dichloromethane and various acids (10% v/v). (ii) The necessity to use powerful oxidants such as ferric chloride (FeCl3) or DDQ/H+ for Scholl reactions is inconsistent with the arenium-ion mechanism in light of the fact that aromatization of the dihydro intermediates (formed via arenium-ion mechanism) can be easily accomplished with rather weak oxidants such as iodine or air. (iii) Various Scholl precursors with oxidation potentials 1.7 V vs SCE undergo ready oxidative C-C bond formation with DDQ/H+ as oxidant, whereas Scholl precursors with oxidation potentials greater than >1.7 V vs SCE do not react. (iv) Finally, the feasibility of the dicationic intermediate, formed by loss of two electrons, has been demonstrated by its generation from a tetraphenylene derivative using DDQ/H+ as an oxidant.
Method for preparing aminoarylborane compounds or derivatives thereof
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, (2015/06/17)
The present invention provides a process for the preparation of aminoarylborane compounds and derivatives thereof comprising a step of arylation by reacting an aryl chloride with an aminoborane compound in the presence of a catalytic system. Typically, th
Amine-borane complexes: Air- and moisture-stable partners for palladium-catalyzed borylation of aryl bromides and chlorides
Guerrand, Hélène D. S.,Vaultier, Michel,Pinet, Sandra,Pucheault, Mathieu
, p. 1167 - 1174 (2015/04/22)
A method for using amine-borane complexes directly in palladium catalyzed borylation has been developed. The reaction proceeds through the sequential formation of a boronium species followed by deprotonation leading to the aminoborane. This reagent is then directly used in the borylation process leading, after work-up, to various boronic acid derivatives. The reaction was applied to (hetero)aryl triflates, iodides, bromides and chlorides.
Borylation using group IV metallocene under mild conditions
Marciasini, Ludovic D.,Vaultier, Michel,Pucheault, Mathieu
supporting information, p. 1702 - 1705 (2014/03/21)
A borylation reaction of aromatic diazonium salts has been optimized using titanocene and zirconocene derivatives as catalysts. The reaction employs diisopropylaminoborane as a borylating agent and proceeds smoothly at room temperature to provide arylboronates after methanolysis and transesterification with pinacol. The reaction mechanism has been found to proceed via a radical pathway.
Mn-catalyzed aromatic C-H alkenylation with terminal alkynes
Zhou, Bingwei,Chen, Hui,Wang, Congyang
supporting information, p. 1264 - 1267 (2013/03/14)
The first manganese-catalyzed aromatic C-H alkenylation with terminal alkynes is described. The procedure features an operationally simple catalyst system containing commercially available MnBr(CO)5 and dicyclohexylamine (Cy2NH). The reaction occurs readily in a highly chemo-, regio-, and stereoselective manner delivering anti-Markovnikov E-configured olefins in high yields. Experimental study and DFT calculations reveal that (1) the reaction is initiated by a C-H activation step via the cooperation of manganese and base; (2) manganacycle and alkynylmanganese species are the key reaction intermediates; and (3) the ligand-to-ligand H-transfer and alkynyl-assisted C-H activation are the key steps rendering the reaction catalytic in manganese.
