7116-97-4Relevant academic research and scientific papers
Iron-catalyzed cross coupling of aryl chlorides with alkyl Grignard reagents: Synthetic scope and FeII/FeIV mechanism supported by x-ray absorption spectroscopy and density functional theory calculations
Agata, Ryosuke,Takaya, Hikaru,Matsuda, Hiroshi,Nakatani, Naoki,Takeuchi, Katsuhiko,Iwamoto, Takahiro,Hatakeyama, Takuji,Nakamura, Masaharu
supporting information, p. 381 - 390 (2019/02/25)
A combination of iron(III) fluoride and 1,3-bis(2,6-diiso-propylphenyl)imidazolin-2-ylidene (SIPr) catalyzes the high-yielding cross coupling of an electron-rich aryl chloride with an alkyl Grignard reagent, which cannot be attained using other iron catalysts. A variety of alkoxy-or amino-substituted aryl chlorides can be cross-coupled with various alkyl Grignard reagents regardless of the presence or absence of β-hydrogens in the alkyl group. A radical probe experiment using 1-(but-3-enyl)-2-chlorobenzene does not afford the corresponding cyclization product, therefore excluding the intermediacy of radical species. Solution-phase X-ray absorption spectroscopy (XAS) analysis, with the help of density functional theory (DFT) calculations, indicates the formation of a high-spin (S = 2) heteroleptic difluorido organoferrate(II), [MgX][FeIIF2(SIPr)-(Me/alkyl)], in the reaction mixture. DFT calculations also support a feasible reaction pathway, including the formation of a difluorido organoferrate(II) intermediate which undergoes a novel Lewis acid-assisted oxidative addition to form a neutral organoiron(IV) intermediate, which leads to an FeII/FeIV cata-lytic cycle, where the fluorido ligand and the magnesium ion play key roles.
Nickel-catalyzed alkyl-alkyl cross-coupling reactions of non-activated secondary alkyl bromides with aldehydes as alkyl carbanion equivalents
Zhu, Chenghao,Zhang, Junliang
, p. 2793 - 2796 (2019/03/06)
A novel nickel-catalyzed alkyl-alkyl cross coupling of non-activated secondary alkyl bromides with aldehydes via hydrazone intermediates has been developed. Aldehydes as alkyl carbanion equivalents replace traditional organometallic reagents. This coupling occurs on the carbon of the hydrazone rather than the nitrogen. In addition, non-activated primary and tertiary alkyl bromides also undergo the cross-coupling reaction to form new C(sp3)-C(sp3) bonds in moderate yields.
UVA- and Visible-Light-Mediated Generation of Carbon Radicals from Organochlorides Using Nonmetal Photocatalyst
Matsubara, Ryosuke,Yabuta, Tatsushi,Md Idros, Ubaidah,Hayashi, Masahiko,Ema, Fumitoshi,Kobori, Yasuhiro,Sakata, Ken
, p. 9381 - 9390 (2018/07/25)
Carbon radicals are reactive species useful in various organic transformations. The C-X bond cleavage of organohalides by photoirradiation is a common method to generate carbon radicals in a controlled fashion. The use of organochloride substrates is still a formidable challenge due to the low reduction potential and the high dissociation energy of the C-Cl bond. In this report, we address these issues by using a nonmetal organic molecule with a relatively simple structure as a photocatalyst. In this catalyst (bis(dimethylamino)carbazole), the amino groups increase both the HOMO and LUMO energy levels, especially in the former. As a result, compared to the parent molecule, the new catalyst shows experimentally red-shifted absorption in the visible region and forms an excited state with better reducing capability. This photocatalyst was used in the reduction of unactivated aryl chlorides and alkyl chlorides in the presence of hydrogen atom donor at room temperature. The catalytic system can also be applied to the coupling of aryl chlorides with electron-rich arene and heteroarenes to affect the C-C bond-forming reactions. Our mechanistic study results support the assumption that carbon radicals are formed from the organochlorides via a single-electron-transfer step.
Iron fluoride/N-heterocyclic carbene catalyzed cross coupling between deactivated aryl chlorides and alkyl grignard reagents with or without β-hydrogens
Agata, Ryosuke,Iwamoto, Takahiro,Nakagawa, Naohisa,Isozaki, Katsuhiro,Hatakeyama, Takuji,Takaya, Hikaru,Nakamura, Masaharu
, p. 1733 - 1740 (2015/06/16)
High-yielding cross-coupling reactions of various combinations of aryl chlorides and alkyl Grignard reagents have been developed by using an iron(III) fluoride/1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene (SIPr) catalyst composite. The iron(III) fluoride/SIPr-catalyzed aryl-alkyl coupling demonstrates unprecedented scope for both aryl chlorides and alkyl Grignard reagents, thus enabling the first efficient coupling of electron-rich (deactivated) aryl chlorides with alkyl Grignard reagents without β-hydrogens. The present reaction is also effective for diverse alkyl Grignard reagents such as (trimethylsilyl)methyl, primary, and secondary alkyl Grignard reagents.
Catalytic activity of 1-methylimidazole-based phosphine ligands in the palladium-catalyzed Suzuki coupling reaction
Guan, Jin Tao,Song, Xiao Ming,Zhang, Zhi Yong,Wei, Ben Mei,Dai, Zhi Qun
, p. 87 - 89 (2015/01/30)
The catalytic activities of three N-methylimidazole-based phosphine ligands in the Suzuki coupling reaction were tested using PdCl2 as the catalyst. The results showed all three phosphine ligands exhibited excellent activity towards the Suzuki reaction, and the catalytic activity decreased with increasing number of imidazole groups.
Iron-catalyzed cross-coupling reaction of alkyl halides with biphenyl grignard reagent
Dai,Liu,Zhang,Wei,Guan
, p. 6303 - 6305 (2013/07/26)
In the presence of a catalytic amount of iron salts and N,N,N',N'-tetramethylethylene diamine as additive, alkyl bromide reacted with biphenyl magnesium bromide to obtain the cross-coupling product in good yields. The suitable amount of catalyst and the additive are 5 % mol (based on alkyl bromide), 1.3 equiv(based on alkyl bromide), respectively. Under the optimal conditions, the yields of the crosscoupling could reach up to 92.3 %.
Dinuclear iron complex-catalyzed cross-coupling of primary alkyl fluorides with aryl grignard reagents
Mo, Zhenbo,Zhang, Qiang,Deng, Liang
, p. 6518 - 6521 (2012/10/29)
Iron-catalyzed cross-coupling of nonactivated primary alkyl fluorides with aryl Grignard reagents has been achieved by using the low-coordinate dinuclear iron complex [(IPr2Me2)Fe(μ2-NDipp) 2Fe(IPr2Me2)] as the catalyst. This iron-catalyzed C(sp3)-F bond arylation reaction is applicable to a variety of aryl Grignard reagents and primary alkyl fluorides. The product pattern suggests the involvement of a radical-type mechanism for its C-F bond scission step.
Palladium-catalyzed Suzuki cross-coupling reactions in a microemulsion
Vashchenko, Valery,Krivoshey, Alexander,Knyazeva, Irina,Petrenko, Alexey,Goodby, John W.
, p. 1445 - 1449 (2008/09/18)
An enhancement of palladium-catalyzed Suzuki cross-coupling reactions between substrates possessing long-chain alkyl or oxyalkyl substituents in two-phase media, in the presence of sodium dodecylsulfate, is shown. Quantitative evaluations of the influence of SDS on the reaction rates were determined.
SYNTHESIS OF 4-ALKYL-4'-CYANOBIPHENYLS
Ruolene, Yu. I.,Adomenas, P. V.,Sirutkaitis, R. A.,Denis, G. I.
, p. 1187 - 1191 (2007/10/02)
Liquid crystals of the 4-alkyl-4'-cyanobiphenyl group were synthesized without the use of copper cyanide. 4-Alkyl-4'-formylbiphenyls and the 4-formyloximes of 4'-alkylbiphenyl, which possess a liquid-crystalline state, were isolated.Beginning with the pentyl homolog, they form an enantiotropic nematic phase, and beginning with octyl homolog they also form a smectic meso phase.
