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Updated: Jun 16, 2026
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
New catalytic system for aminohalogenation of beta-methyl-beta-nitrostyrenes to give opposite regiochemistry
San-Jun Zhi1, Hao Sun, Guangqian Zhang
1School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, PR China.
Abstract:
A new combination of catalyst and co-additive has been found for aminohalogenation reaction of beta-methyl-beta-nitrostyrenes with N,N-dichloro-p-tolunesulfonamide (4-TsNCl(2)). The reaction was achieved by using MnSO(4) as the catalyst together with tolunesulfonamide to give vicinal haloamino nitroalkanes with opposite regiochemistry to that generated from other electron-deficient olefins observed previously. The reaction proceeded smoothly at room temperature under nitrogen atmosphere to give useful to good yields and excellent regio and stereoselectivity. A mechanism involving the formation of chloronium intermediate was proposed to explain the resulting regio and stereochemistry.
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