Cyclisation of carbinyl radicals onto imines and hydrazones
作者:W.Russell Bowman、Peter T. Stephenson、Nicholas K. Terrett、Adrian R. Young
DOI:10.1016/s0040-4039(00)73435-6
日期:1994.8
The regioselectivity of intramolecular addition of sp(3) carbon-centred radicals onto C=N double bonds of imines and hydrazones is influenced by the position and polarisation of the C=N bond.
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。
Radical cyclisations of imines and hydrazones
作者:W. Russell Bowman、Peter T. Stephenson、Nicholas K. Terrett、Adrian R. Young
DOI:10.1016/0040-4020(95)00412-2
日期:1995.7
Radical cyclisation of sp3 carbon-centred radicals onto imines and hydrazones provides a new method for the synthesis of 5- and 6-membered ring nitrogen heterocycles. Cyclisation onto the electrophilic carbon of the C=N group and 5-exo stereoelectronic selectivity are the dominating mechanistic parameters. The C-centred radical intermediates were generated from benzeneselenyl precursors using Bu3SnH