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Upstream product

• 623-12-1 4-chloromethoxybenzene 
• 104-92-7 1-bromo-4-methoxy-benzene 
• 136068-05-8 1-(2-phenylethyl)cyclopropanol 
• 103-25-3 3-phenylpropanoic acid methyl ester 
• 104-53-0 3-phenyl-propionaldehyde 
• 637-69-4 4-Methoxystyrene 
• 1929-29-9 3-(4-methoxyphenyl)propanoic acid 
• 2550-26-7 4-Phenyl-2-butanone 
• 2393-23-9 4-methoxy-benzylamine 
• 100-51-6 benzyl alcohol 
• 2344-70-9 1-phenyl-3-butanol 
• 105-13-5 4-Methoxybenzyl alcohol 
• 208453-06-9 3-(4-methoxyphenyl)propionic acid ethanethiol ester 

Relevant academic research and scientific papers

KETONE SYNTHESIS AND APPLICATIONS

Provided are new nickel./zirconium-mediated coupling reactions useful in the synthesis of ketone-containing compounds, e.g., halichondrin natural products and related molecules. A feature of the present disclosure is the use of a nickel(I) catalyst in tandem with a nickel (II) catalyst in the Ni/Zr-mediated coupling reactions. Without wishing to be bound by any particular theory, the nickel (I) catalyst selectively activates the electrophilic coupling partner (i.e., the compound of Formula (A)), and the nickel(ll) catalyst selectively activates the nucleophilic coupling partner (i.e., a thioester of Formula (B)). This dual catalyst system leads to improved coupling efficiency and eliminates the need for a large excess of one of the coupling partners (i.e., a compound of Formula (A) or (B)).

Scope and Mechanism of the Redox-Active 1,2-Benzoquinone Enabled Ruthenium-Catalyzed Deaminative α-Alkylation of Ketones with Amines

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 intramolecular [1,3]-alkyl migration of an Ru-enamine intermediate has been compiled on the basis of these experimental and computational data.

Ti(O iPr)4-Enabled Dual Photoredox and Nickel-Catalyzed Arylation and Alkenylation of Cyclopropanols

Readily available from esters or ketones, cyclopropanols are inclined to undergo diverse ring-opening transformations. Their one-electron oxidation is a conventional way to β-carbonyl radicals. However, despite this fact, their application as a coupling partner in dual photoredox and nickel-catalyzed reactions with organic halides remains underdeveloped. Here, we report that the Ti(OiPr)4 additive enables this elusive cross-coupling with aryl and alkenyl bromides leading to β-substituted ketones.

Nickel-Catalyzed Hydroacylation of Styrenes with Simple Aldehydes: Reaction Development and Mechanistic Insights

The first nickel-catalyzed intermolecular hydroacylation reaction of alkenes with simple aldehydes has been developed. This reaction offers a new approach to the selective preparation of branched ketones in high yields (up to 99%) and branched selectivities (up to 99:1). Experimental data provide evidence for reversible formation of acyl-nickel-alkyl intermediate, and DFT calculations show that the aldehyde C-H bond transfer to a coordinated alkene without oxidative addition is involved. The origin of the reactivity and regioselectivity of this reaction was also investigated computationally, which are consistent with experimental observations.

Oxidation and β-Alkylation of Alcohols Catalysed by Iridium(I) Complexes with Functionalised N-Heterocyclic Carbene Ligands

The borrowing hydrogen methodology allows for the use of alcohols as alkylating agents for C-C bond forming processes offering significant environmental benefits over traditional approaches. Iridium(I)-cyclooctadiene complexes having a NHC ligand with a O- or N-functionalised wingtip efficiently catalysed the oxidation and β-alkylation of secondary alcohols with primary alcohols in the presence of a base. The cationic complex [Ir(NCCH3)(cod)(MeIm(2- methoxybenzyl))][BF4] (cod=1,5-cyclooctadiene, MeIm=1-methylimidazolyl) having a rigid O-functionalised wingtip, shows the best catalyst performance in the dehydrogenation of benzyl alcohol in acetone, with an initial turnover frequency (TOF0) of 1283 h-1, and also in the β-alkylation of 2-propanol with butan-1-ol, which gives a conversion of 94 % in 10 h with a selectivity of 99 % for heptan-2-ol. We have investigated the full reaction mechanism including the dehydrogenation, the cross-aldol condensation and the hydrogenation step by DFT calculations. Interestingly, these studies revealed the participation of the iridium catalyst in the key step leading to the formation of the new C-C bond that involves the reaction of an O-bound enolate generated in the basic medium with the electrophilic aldehyde.

Palladium-catalyzed cross-coupling of cyclopropanol-derived ketone homoenolates with aryl bromides

The cross-coupling reaction of cyclopropanol-derived ketone homoenolates bearing β-hydrogens with aryl and hetaryl bromides has been achieved for the first time. This reaction is high yielding, is broad in scope and uses a simple catalytic system. Notably, the proposed palladium homoenolates do not undergo β-hydride elimination to the corresponding α,β- unsaturated ketones.

Scope of the suzuki-miyaura cross-coupling reaction of potassium trifluoroboratoketohomoenolates

Potassium trifluoroboratoketohomoenolates were prepared in good yields from either the corresponding α,β-unsaturated compounds or methyl ketones. These organoboron reagents were effectively cross-coupled with various aryl and heteroaryl chlorides.

A novel ketone synthesis by a palladium-catalyzed reaction of thiol esters and organozinc reagents

A variety of ketones have been prepared by a palladium-catalyzed reaction of ethanethiol esters with organozinc reagents. Various functional groups, including esters, ketones, aromatic halides and aldehydes, tolerate the reaction conditions. The reaction can also be applied to the synthesis of α-amino ketones using the corresponding L-α-amino thiol esters without racemization.