898792-14-8Relevant academic research and scientific papers
C(sp3)-H Bond Acylation with N -Acyl Imides under Photoredox/ Nickel Dual Catalysis
Kerackian, Taline,Reina, Antonio,Krachko, Tetiana,Boddaert, Hugo,Bouyssi, Didier,Monteiro, Nuno,Amgoune, Abderrahmane
supporting information, p. 1531 - 1536 (2020/10/21)
A novel Ni/photoredox-catalyzed acylation of aliphatic substrates, including simple alkanes and dialkyl ethers, has been developed. The method combines C-N bond activation of amides with a radical relay mechanism involving hydrogen-atom transfer. The protocol is operationally simple, employs bench-stable N -acyl imides as acyl-transfer reagents, and permits facile access to alkyl ketones under very mild conditions.
Cross-Coupling of Secondary Amides with Tertiary Amides: The Use of Tertiary Amides as Surrogates of Alkyl Carbanions for Ketone Synthesis
Wang, Shu-Ren,Huang, Pei-Qiang
, p. 887 - 891 (2019/07/18)
In recent years, exciting progress has been made in the field of direct transformation of amides, nevertheless, the condensation between two amides remains rare and restricted to homo-coupling reactions. Herein, we report the cross-coupling of secondary amides with tertiary amides, which provides a synthesis of ketones under mild conditions, and features the use of tertiary amides as surrogates of alkyl carbanions. The method relies on the coupling of enamines, generated from tertiary amides by catalytic partial reduction of tertiary amides with Vaska's catalyst, with nitrilium ions, formed in situ from secondary amides via activation with trifluoromethanesulfonic anhydride, and on the subsequent deformylation.
A Nickel-Catalyzed Carbonyl-Heck Reaction
Vandavasi, Jaya Kishore,Hua, XiYe,Halima, Hamdi Ben,Newman, Stephen G.
, p. 15441 - 15445 (2017/11/10)
The use of transition-metal catalysis to enable the coupling of readily available organic molecules has greatly enhanced the ability of chemists to access complex chemical structures. In this work, an intermolecular coupling reaction that unites organotriflates and aldehydes is presented. A unique catalyst system is identified to enable this reaction, featuring a Ni0 precatalyst, a tridentate Triphos ligand, and a bulky amine base. This transformation provides access to a variety of ketone-containing products without the selectivity- and reactivity-related challenges associated with more traditional Friedel–Crafts reactions. A Heck-type mechanism is postulated, wherein the π bond of the aldehyde takes the role of the olefin in the insertion/elimination steps.
Synergistic Photoredox/Nickel Coupling of Acyl Chlorides with Secondary Alkyltrifluoroborates: Dialkyl Ketone Synthesis
Amani, Javad,Molander, Gary A.
, p. 1856 - 1863 (2017/02/10)
Visible light photoredox/nickel dual catalysis has been employed in the cross-coupling of acyl chlorides with potassium alkyltrifluoroborates. This protocol, based on single-electron-mediated alkyl transfer, circumvents the restriction of using reactive alkylmetallic nucleophiles in transition-metal-catalyzed acylation and achieves a mild and efficient method for the synthesis of unsymmetrical alkyl ketones. In this approach, a variety of acyl chlorides have been successfully coupled with structurally diverse potassium alkyltrifluoroborates, generating the corresponding ketones with good yields.
Practical one-pot preparation of ketones from aryl and alkyl bromides with aldehydes and DIH via Grignard reagents
Dohi, Souya,Moriyama, Katsuhiko,Togo, Hideo
experimental part, p. 6557 - 6564 (2012/08/27)
Various diaryl ketones, alkyl aryl ketones, and dialkyl ketones were efficiently prepared in good yields by the reactions of the Grignard reagents derived from aryl or alkyl bromides, followed by the reactions with aromatic or aliphatic aldehydes and the subsequent treatment with 1,3-diiodo-5,5- dimethylhydantoin and K2CO3, in a one-pot method. The same treatment of aromatic bromides bearing electron-withdrawing groups, such as ester, nitrile, ketone, and nitro groups with i-PrMgCl·LiCl or PhMgCl instead of Mg, also provided the corresponding diaryl and alkyl aryl ketones in good yields. The above methods are simple and practical transition-metal-free methods for the preparation of various diaryl ketones and alkyl aryl ketones bearing electron-rich aromatic groups and electron-deficient aromatic groups, as well as dialkyl ketones.
Double duty for cyanogen bromide in a cascade synthesis of cyanoepoxides
Li, Zhou,Gevorgyan, Vladimir
supporting information; experimental part, p. 2808 - 2810 (2011/05/05)
An unprecedented reaction mode of cyanogen bromide has been discovered. Under basic conditions, cyanogen bromide acts as an equivalent of both Br + and CN- to convert enolizable ketones into the corresponding cyanoepoxides in good yields. This unique reaction mode provides new, one-pot access to densely substituted cyanoepoxides from easily available ketones (see scheme). Copyright
Palladium-catalyzed synthesis of aryl ketones by coupling of aryl bromides with an acyl anion equivalent
Takemiya, Akihiro,Hartwig, John F.
, p. 14800 - 14801 (2008/02/05)
Palladium-catalyzed couplings of aryl bromides with N-tert-butylhydrazones as acyl anion equivalents to form aryl ketones are reported. The coupling process occurs at the C-position of hydrazones to form N-tert-butyl azo compounds. Isomerization of these azo compounds to the corresponding hydrazones, followed by hydrolysis, gave the desired mixed alkyl aryl ketones. The selectivity of C- versus N-arylation was strongly influenced by the substituent on nitrogen. Arylation at carbon occurred with N-tert-butylhydrazones, whereas N-arylation occurred with N-arylhydrazones. The arylation of hydrazones containing primary and secondary alkyl groups, as well as aryl groups, gave the desired ketones in good yields after hydrolysis. Functional groups on the aromatic ring, such as alkoxy, cyano, trifluoromethyl, carboalkoxy, carbamoyl, and keto groups, were tolerated. This reaction likely occurs by C-C bond-forming reductive elimination from an intermediate containing an η1-diazaallyl ligand. Copyright
