90798-46-2Relevant academic research and scientific papers
Dibrominated addition and substitution of alkenes catalyzed by Mn2(CO)10
Chan, Albert S. C.,Jiang, Yi,Meng, Shanshui,Song, Xianheng,Zhang, Hong,Zou, Yong
supporting information, p. 13385 - 13388 (2021/12/17)
A practical method for the dibromination of alkenes without using molecular bromine is consistently appealing in organic synthesis. Herein, we report Mn-catalyzed dibrominated addition and substitution of alkenes only with N-bromosuccinimide, producing a variety of synthetically valuable dibrominated compounds in moderate to high yields. This journal is
Modular access to 1,2-allenyl ketones based on a photoredox-catalysed radical-polar crossover process
Du, Chan,Fang, Jianghua,Fang, Yewen,Lei, Wan,Li, Yan,Liu, Yongjun
, p. 8502 - 8506 (2021/10/20)
Herein, a new protocol dealing with the preparation of 1,2-allenyl ketones has been successfully developedviathe reactions of enynes with radicals enabled by dual photoredox/copper catalysis. Based on the results of a deuteration experiment and the competition reaction between cyclopropanation and allenation, the mechanism based on a photoredox-neutral-catalysed radical-polar crossover process has been proposed. Synthetic applications of allenes have also been demonstrated.
Synthesis of α,β-dibromo ketones by photolysis of α-bromo ketones with N-bromosuccinimide: Photoinduced β-bromination of α-bromo ketones
Moon, Da Yoon,An, Sejin,Park, Bong Ser
, (2019/10/28)
Irradiation of α-bromopropiophenones in the presence of NBS results in the formation of α,β-dibromopropiophenones, which can be viewed as β-bromination of α-bromopropiophenones. The reaction is believed to go through a series of reactions; photoinduced C–Br bond cleavage, elimination of HBr to give α,β-unsaturated ketone intermediates, and addition of Br2, which are formed by the reaction between HBr and NBS. From mechanistic studies of the reaction, we have also found a very convenient method for α-debromination of the α,β-dibromopropiophenones which is by simple irradiation of the dibromo ketones in acetone or 2-propanol without the use of any additives. Our results demonstrate that bromine can be added into or eliminated from the alpha, beta, or both positions to the carbonyl group by photochemical methods, which make synthetic options of bromine containing carbonyl compounds versatile.
Solvent free, light induced 1,2-bromine shift reaction of α-bromo ketones
An, Sejin,Moon, Da Yoon,Park, Bong Ser
, p. 6922 - 6928 (2018/10/24)
Photolysis of α-bromopropiophenones in acetonitrile results in formation of β-bromopropiophenones with good product selectivity, which can be coined as 1,2-Br shift reaction. The product selectivity increases when the reaction is done in neat or solid state, where only the 1,2-Br shift product is formed in some cases. The reaction is suggested to proceed by C–Br bond homolysis to give a radical pair, followed by disproportionation and conjugate addition of HBr to the α,β-unsaturated ketone intermediate. When the unsaturated intermediate is stabilized by an extra conjugation, the reaction stops at the stage, in which the unsaturated ketone becomes a major product. The synthetic method described in this research fits in a category of eco-friendly organic synthesis nicely since the reaction does not use volatile organic solvents and any other additives such as acid, base or metal catalysts, etc. Besides, the method fits into perfect atom economy, which does not give any side products. The synthetic method should find much advantage over other alternative methods to obtain β-bromo carbonyl compounds.
Trifluoromethanesulfonic anhydride-promoted α-bromination of ketones with Grignard reagent or magnesium bromide
Nishiyama,Ono,Kurokawa,Kimura
, p. 1999 - 2002 (2007/10/03)
The direct α-bromination of various ketones using trifluoromethanesulfonic anhydride and Grignard reagent or magnesium bromide in ether gave the corresponding α-bromo ketones in moderate to good yields under mild reaction conditions.
