Scope and Mechanism of the Redox-Active 1,2-Benzoquinone Enabled Ruthenium-Catalyzed Deaminative α-Alkylation of Ketones with Amines was written by Kirinde Arachchige, Pandula T.;Handunneththige, Suhashini;Talipov, Marat R.;Kalutharage, Nishantha;Yi, Chae S.. And the article was included in ACS Catalysis in 2021.Safety of 1-(5-Bromobenzofuran-2-yl)ethanone This article mentions the following:
The catalytic system formed in situ from the reaction of a cationic Ru-H complex with 3,4,5,6-tetrachloro-1,2-benzoquinone was found to mediate a regioselective deaminative coupling reaction of ketones with amines to form the α-alkylated ketone products. Both benzylic and aliphatic primary amines were found to be suitable substrates for the coupling reaction with ketones in forming the α-alkylated ketone products. The coupling reaction of PhCOCD3 with 4-methoxybenzylamine showed an extensive H/D exchange on both α-CH2 (41% D) and β-CH2 (21%) positions on the alkylation product. The Hammett plot obtained from the reaction of acetophenone with para-substituted benzylamines p-X-C6H4CH2NH2 (X = OMe, Me, H, F, Cl, CF3) showed a strong promotional effect by the amine substrates with electron-releasing groups (ρ = -0.49 ± 0.1). The most significant carbon isotope effect was observed on the α-carbon of the alkylation product (Cα = 1.020) from the coupling reaction of acetophenone with 4-methoxybenzylamine. The kinetics of the alkylation reaction from an isolated imine substrate led to the empirical rate law: rate = k[Ru][imine]. A catalytically active Ru-catecholate complex was synthesized from the reaction of the cationic Ru-H complex with 3,5-di-tert-butyl-1,2-benzoquinone and PCy3. The DFT computational study was performed on the alkylation reaction, which revealed a stepwise mechanism of the [1,3]-carbon migration step via the formation of a Ru(IV)-alkyl species with a moderate energy of activation (ΔG‡ = 32-42 kcal/mol). A plausible mechanism of the catalytic alkylation reaction via an intramol. [1,3]-alkyl migration of an Ru-enamine intermediate has been compiled on the basis of these exptl. and computational data. In the experiment, the researchers used many compounds, for example, 1-(5-Bromobenzofuran-2-yl)ethanone (cas: 38220-75-6Safety of 1-(5-Bromobenzofuran-2-yl)ethanone).
1-(5-Bromobenzofuran-2-yl)ethanone (cas: 38220-75-6) belongs to benzofurans derivatives.Benzofuran is one of the most significant oxygen-containing heterocycles consisting of fused benzene and furan ring, which are widely presented in various naturally occurring and synthetically active compounds. Introduction of benzofurans in organic synthesis, particularly drug synthesis, involves generally the use of their metalated species as nucleophiles in addition reactions or in metal-catalysed cross-coupling reactions.Safety of 1-(5-Bromobenzofuran-2-yl)ethanone
Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem