Evidence for a common selenolate intermediate in the glutathione peroxidase-like catalysis of α-(phenylselenenyl) ketones and diphenyl diselenide
作者:Lars Engman、Claes Andersson、Ralf Morgenstern、Ian A. Cotgreave、Carl-Magnus Andersson、Anders Hallberg
DOI:10.1016/s0040-4020(01)87004-6
日期:1994.2
glutathione peroxidase-like catalysis of α-(phenylselenenyl) ketones was investigated. Degradation studies demonstrated the rapid cleavage of the aliphatic carbon-selenium bond of α-(phenylselenenyl) ketones by glutathione at pH 6.9 in a methanolic phosphate buffer under argon. On treatment with excess glutathione under aerobic conditions, α-(phenylselenenyl) ketones, S-(phenylselenenyl)glutathione and
A novel route to cyclic imines based on 5-exo radicalcyclization is explored. The radical precursors are imines prepared from allylamine and readily available α-phenylselenenyl ketones.
Phenyl selenium trichloride in synthesis. Reaction with ketones. A new variation of the selenoxide elimination reaction
作者:Lars Engman
DOI:10.1016/s0040-4039(01)84605-0
日期:——
Phenyl selenium trichloride was used for the introduction of a PhSeCl2-group into the α-position of ketones. These products were converted to enones (hydrolysis/selenoxide elimination) or α-phenylselenoketones (thiourea-reduction).
General synthesis of alkyl phenyl selenides from organic halides mediated by zinc in aqueous medium
作者:Lothar W Bieber、Ana C.P.F de Sá、Paulo H Menezes、Simone M.C Gonçalves
DOI:10.1016/s0040-4039(01)00820-6
日期:2001.7
halides of different structural types react with diphenyl diselenide and zinc dust in aqueous medium to give alkyl phenyl selenides. Benzylic and allylic bromides, α-bromoesters, acids and ketones and some primary alkyl iodides produce high yields even under acidic conditions. Less reactive halides need basic medium. The reaction proceeds equally well in the presence of various unprotected functional
不同结构类型的有机卤化物与二苯基二硒化物和锌粉在水性介质中反应,生成烷基苯基硒化物。苄基和烯丙基溴化物,α-溴代酸酯,酸和酮以及某些伯烷基碘化物即使在酸性条件下也能产生高收率。反应性较低的卤化物需要基本介质。在各种未保护的官能团的存在下,反应同样良好地进行。对照实验通过烷基支持S H 2机理。
Preparation of silyl enol ethers derived from α-phenylseleno aldehydes and α-phenylseleno ketones
experimental conditions for the preparation of trimethylsilyl enolethers 3 from α-phenylseleno aldehydes 1, compatible with a limited deselenenylation of the substrate, were studied. Starling from α-phenylseleno ketones 2, the enoxysilanes 4, bearing a vinylic PhSe group, are the major products when triethylamine is the base. Trimethylsilyl enolethers 5 with an allylic PhSe group arc also formed beside 4