69151-18-4

Upstream product

• 766-96-1 4-bromo-1-ethynylbenzene 
• 3712-44-5 2,2,2-tribromo-1,3,2-benzodioxaphosphole 
• 27296-45-3 2,2-dibromo-2-fluoro-benzo[d]-1,3,2-dioxaphosphole 
• 33458-10-5 1-bromo-4-(1,2-dibromoethyl)benzene 
• 2039-82-9 1-bromo-4-ethenyl-benzene 
• 75230-51-2 4-bromoacetophenone tosylhydrazone 
• 99-90-1 para-bromoacetophenone 
• 74-95-3 1,1-dibromomethane 
• 690275-01-5 4'-bromoacetophenone N-tert-butyldimethylsilylhydrazone 

Downstream Products

• 99-73-0 para-bromophenacyl bromide 
• 30913-87-2 4-(4-bromophenyl)-4-oxobutanoic acid ethyl ester 
• 1159205-36-3 diethyl 1-(4-bromophenyl)ethenylphosphonate 
• 41024-55-9 1-(4-bromophenyl)-2-(phenylsulfonyl)ethanone 
• 92975-14-9 4,4'-(buta-1,3-diene-2,3-diyl)bis(bromobenzene) 

Relevant academic research and scientific papers

Synthesis of Unsymmetrical 1,4-Dicarbonyl Compounds by Photocatalytic Oxidative Radical Additions

Herein we report a photocatalytic oxidative radical addition reaction for the synthesis of unsymmetrical 1,4-dicarbonyl compounds. This reaction utilizes a desulfurization process to generate electrophilic radicals, which add to α-halogenated alkenes and undergo further oxidation to deliver 1,4-dicarbonyl compounds. This mild and highly efficient method provides a valuable alternative to known strategies.

Green and Efficient: Iron-Catalyzed Selective Oxidation of Olefins to Carbonyls with O2

A mild and operationally simple iron-catalyzed protocol for the selective aerobic oxidation of aromatic olefins to carbonyl compounds is described. Catalyzed by a Fe(III) species bearing a pyridine bisimidazoline ligand at 1 atm of O2, α- and β-substituted styrenes were cleaved to afford benzaldehydes and aromatic ketones generally in high yields with excellent chemoselectivity and very good functional group tolerance, including those containing radical-sensitive groups. With α-halo-substituted styrenes, the oxidation took place with concomitant halide migration to afford α-halo acetophenones. Various observations have been made, pointing to a mechanism in which both molecular oxygen and the olefinic substrate coordinate to the iron center, leading to the formation of a dioxetane intermediate, which collapses to give the carbonyl product. (Chemical Equation).

Regioselective Synthesis of Vinyl Halides, Vinyl Sulfones, and Alkynes: A Tandem Intermolecular Nucleophilic and Electrophilic Vinylation of Tosylhydrazones

A diazo species is trapped in an intermolecular fashion by two independent ion species in tandem at the carbene center to install an electrophile and a nucleophile on the same carbon. This metal-free concept, which is unprecedented, has been illustrated by regioselective synthesis of a variety of vinyl halides, vinyl sulfones, and alkyne derivatives. (Chemical Equation Presented).

Metal-free regioselective hydrobromination of alkynes through CH/CBr activation

A metal-free regioselective hydrobromination of alkynes has been developed to provide the Markovnikov-type vinyl bromides in good yields using dibromomethane/N,N-dimethylaniline as in-situ 'HBr' source. This protocol also represents an elegant example of the activation of sp2 CH and CBr bonds in one pot, in which 'HBr' is generated and transferred under mild metal-free conditions. D-incorporated experiments were employed to investigate the reaction mechanism and a plausible reaction path was proposed.

Practical Procedures for the Preparation of N-tert-Butyldimethylsilylhydrazones and Their Use in Modified Wolff-Kishner Reductions and in the Synthesis of Vinyl Halides and gem-Dihalides

In this work we develop practical chemistry for the preparation of N-tert-butyldimethylsilylhydrazone (TBSH) derivatives from carbonyl-containing compounds and show that these products serve as superior alternatives to simple hydrazones in Wolff-Kishner-type reduction reactions, in the Barton vinyl iodide preparation, in the synthesis of vinyl bromides, and in the synthesis of gem-diiodides, gem-dibromides, and gem-dichlorides. In our new procedure for silyl hydrazone synthesis, aliphatic and aromatic ketones and aldehydes are shown to undergo highly efficient coupling (typically >95% yield) to form the corresponding TBSH derivatives when combined with equimolar amounts of 1,2-bis(tert-butyldimethylsilyl)-hydrazine (BTBSH) and a catalytic quantity of scandium trifluoromethanesulfonate (typically, 0.01 mol %), neat, or in solvent. Optimized procedures are provided for the use of TBSH derivatives in a Wolff-Kishner-type reduction protocol that proceeds at low temperature (23-100 °C) and in a single reaction flask. Similarly, protocols for the use of TBSH derivatives as precursors to vinyl halides and gem-dihalides are described in detail.