42956-39-8Relevant academic research and scientific papers
(PCy3)2Cl2Ru = CHPh Catalyzed Kharasch additions. Application in a formal olefin carbonylation
Lee, Belinda T.,Schrader, Thomas O.,Martín-Matute, Belén,Kauffman, Christopher R.,Zhang, Peng,Snapper, Marc L.
, p. 7391 - 7396 (2004)
(PCy3)2Cl2RuCHPh-catalyzed Kharasch additions of trihaloalkanes across olefins provide polyhalogenated adducts, which upon hydrolysis furnish α,β-unsaturated ketones, aldehydes, or γ-hydroxybutenolides. This two-step process represents an overall acylation or carbonylation of an olefin.
Hydroalkylation of Aryl Alkenes with Organohalides Catalyzed by Molybdenum Oxido Based Lewis Pairs
Belaj, Ferdinand,Dupé, Antoine,Kloki?, Sumea,M?sch-Zanetti, Nadia C.,Milinkovi?, Angela,Neshchadin, Dmytro,Rodi?, Dado,Walg, Simon,Zwettler, Niklas
, (2020/07/06)
Three molybdenum(VI) dioxido complexes [MoO2(L)2] bearing Schiff base ligands were reacted with B(C6F5)3 to afford the corresponding adducts [MoO{OB(C6F5)3}(L)2], which were fully characterized. They exhibit Frustrated Lewis-Pairs reactivity when reacting with silanes. Especially, the [MoO{OB(C6F5)3}(L)2] complex with L=2,4-dimethyl-6-((phenylimino)methyl)phenol proved to be active as catalyst for the hydroalkylation of aryl alkenes with organohalides and for the Atom-Transfer Radical Addition (ATRA) of organohalides to aliphatic alkenes. A series of gem-dichloride and gem-dibromide compounds with potential for further derivatization were synthesized from simple alkenes and organohalides, like chloroform or bromoform, using low catalyst loading. (Figure presented.).
Efficient Pincer-Ruthenium Catalysts for Kharasch Addition of Carbon Tetrachloride to Styrene
Das, Kanu,Dutta, Moumita,Das, Babulal,Srivastava, Hemant Kumar,Kumar, Akshai
, p. 2965 - 2980 (2019/04/30)
A series of NNN pincer-ruthenium complexes (R2NNN)RuCl2(PPh3) (R=Cyclohexyl (Cy), t-butyl (tBu), i-propyl (iPr) and phenyl (Ph)) have been synthesized and characterized. These pincer-ruthenium complexes have been used to catalyse the Kharasch addition or atom transfer radical addition (ATRA) of carbon tetrachloride to styrene. Among the pincer-ruthenium catalysts screened for the Kharasch addition, the catalytic activity followed the order (Cy2NNN)RuCl2(PPh3)>(iPr2NNN)RuCl2(PPh3)?(Ph2NNN)RuCl2(PPh3). The oxidation of Ru(II) is easier with (Cy2NNN)RuCl2(PPh3) and (iPr2NNN)RuCl2(PPh3) in comparison with (Formula presented.) RuCl2(PPh3) as indicated by cyclic voltammetry studies. The catalyst precursor (R2NNN)RuCl2(PPh3) itself is the resting state of the reaction. The rate determining step involves the generation of the five-coordinate 16-electron ruthenium(II) species (R2NNN)RuCl2. Owing to weaker binding of triphenyl phosphine to ruthenium, the generation of catalytically active 16-electron species (Cy2NNN)RuCl2 and (iPr2NNN)RuCl2 are more favourable. The complex (Cy2NNN)RuCl2(PPh3) demonstrates very high productivity (5670 turnovers after 48 h at 140 °C) in the absence of any co-catalyst radical initiator. To the best of our knowledge, our turnovers (ca. 5670) are much higher than that reported hitherto. Quantum mechanical calculations demonstrate that the path involving the activation of carbon tetrachloride by (Cy2NNN)RuCl2 is more favoured than the path where carbon tetrachloride is activated by (Cy2NNN)RuCl2(η2-styrene). Density functional theory (DFT) and kinetic studies are in accord with the widely accepted mechanism involving the single electron transfer (SET) from ruthenium(II) to chloride radical with concomitant generation of a benzyl radical which is trapped by the resulting ruthenium(III) species. (Figure presented.).
A half-sandwich 1,2-azaborolyl ruthenium complex: Synthesis, characterization, and evaluation of its catalytic activities
Liu, Zicheng,Xu, Junjie,Ruan, Wenqing,Fu, Chen,Zhang, Hui-Jun,Wen, Ting-Bin
supporting information, p. 11976 - 11980 (2013/09/02)
A half-sandwich 1,2-azaborolyl (Ab) ruthenium complex, (Ab-CCPh) RuCl(PPh3)2 (1), has been synthesized by treating RuCl2(PPh3)3 with lithium 1,2-azaborolide L-1, or by treating either RuCl2(PPh3)3 or RuHCl(PPh3)3 directly with 1,2-azaborole LH-1. It is evaluated as a suitable precatalyst in [2 + 2] cycloadditions of norbornene derivatives with DMAD and in atom transfer radical additions of halogenated compounds with olefins. The Royal Society of Chemistry.
Controlled homopolymerization of multi-vinyl monomers: Dendritic polymers synthesized via an optimized ATRA reaction
Zheng, Yu,Zhao, Tianyu,Newland, Ben,Poly, Julien,Wang, Wenxin
supporting information, p. 10124 - 10126 (2013/10/22)
In this study, we have managed to find the optimal ATRA system that can obtain the highest mono-adduct yields with the purpose of minimizing the chain growth of divinyl monomers. The most highly hyperbranched polymers have been synthesized by the homopoly
Photoinitiated ambient temperature copper-catalyzed atom transfer radical addition (ATRA) and cyclization (ATRC) reactions in the presence of free-radical diazo initiator (AIBN)
Balili, Marielle Nicole C.,Pintauer, Tomislav
experimental part, p. 3060 - 3066 (2011/05/13)
The use of UV light in copper-catalyzed atom transfer radical addition (ATRA) and cyclization (ATRC) reactions of various (poly)halogenated compounds to highly active alkenes in the presence of AIBN is reported. Radicals generated from photodecomposition of AIBN efficiently regenerated the copper(i) complex at ambient temperature enabling ATRA of CCl4 and CBr4 with catalyst loadings as low as 0.05 mol-%. The desired monoadduct was obtained in lower yields in the ATRA of less active halogenated compounds, which was mostly due to incomplete alkene conversions. Ambient temperature ATRA of CCl 4 to various 1,6-dienes followed by sequential ATRC was also performed in the presence of UV light using [CuII(TPMA)Cl][Cl] complex and AIBN. High yields of the 5-exo-trig cyclic product were obtained for all dienes with preferential formation of the cis isomer. The Royal Society of Chemistry 2011.
Atom transfer radical addition (ATRA) catalyzed by copper complexes with tris[2-(dimethylamino)ethyl]amine (Me6TREN) ligand in the presence of free-radical diazo initiator AIBN
Eckenhoff, William T.,Pintauer, Tomislav
experimental part, p. 4909 - 4917 (2011/06/27)
In this article, we focus on the evaluation of tris[2-(dimethylamino)ethyl] amine (Me6TREN) ligand in copper catalyzed ATRA in the presence of free-radical diazo initiator AIBN (2,2′-azobis(2-methylpropionitrile)). The addition of carbon tetrac
Ruthenium vs. osmium complexes as catalysts for atom transfer radical addition reactions
Fernandez-Zumel, Mariano A.,Kiefer, Gregor,Thommes, Katrin,Scopelliti, Rosario,Severin, Kay
experimental part, p. 3596 - 3601 (2011/01/07)
The catalytic activity of [Cp*OsBr2(PPh 3)] in conjunction with Mg has been evaluated for atom transfer radical addition (ATRA) and cyclization (ATRC) reactions. The Os complex enabled these reactions to be performed with
Olefin cyclopropanations via sequential atom transfer radical addition-dechlorination reactions
Thommes, Katrin,Severin, Kay
scheme or table, p. 188 - 190 (2011/07/07)
In organic synthesis, cyclopropanation reactions are often performed with Simmons-Smith-type reagents or by transition metal catalyzed reactions of olefins with diazo compounds. A novel method for the synthesis of substituted cyclopropanes is described that is based on a two-step reaction sequence. Olefins are reacted with 1,1'-dichlorides in a Ru-catalyzed atom transfer radical addition (ATRA) process and the resulting 1,3-dichlorides are directly converted into cyclopropanes by reductive coupling with magnesium. This one-pot procedure is applicable to a variety of substrates and can be performed in an inter- or intramolecular fashion. Schweizerische Chemische Gesellschaft.
Highly efficient ambient-temperature copper-catalyzed atom-transfer radical addition (ATRA) in the presence of free-radical initiator (V-70) as a reducing agent
Pintauer, Tomislav,Eckenhoff, William T.,Ricardo, Carolynne,Balili, Marielle N. C.,Biernesser, Ashley B.,Noonan, Sean J.,Taylor, Matthew J. W.
supporting information; experimental part, p. 38 - 41 (2009/06/17)
Highly efficient, ambient-temperature, copper-catalyzed Atom Transfer Radical Addition (ATRA) of polyhalogenated compounds to alkenes in the presence of free radical initiator 2,2' -azobis (4-methoxy-2,4-dimethyl valeronitrile)(V-70)as a reducing agent was reported. The discrepancies between the alkene conversion and percent yield were mostly due to competing free-radical polymerization. ATRA of polyhalogenated compounds to monomers that are highly active in free-radical polymerization was not successful at 60 ° C when AIBN was used as radical initiator. The V-70 was proved to be very effective reducing agent, enabling selective formation of the monoadduct with α -olefins and highly active monomers such as methyl acrylate, methyl methacrylate, and vinyl acetate. The methodology for catalyst regeneration in copper-mediated ATRA in the presence of V-70 as a reducing agent also worked very well in the addition of CCl4 and CBr4 to highly active vinyl acetate.
