Tin-Free Radical Cyclizations for the Synthesis of 7-Azaoxindoles, 7-Azaindolines, Tetrahydro[1,8]naphthyridines, and Tetrahydro-5H-pyrido[2,3-b]azepin-8-ones
摘要:
Compounds containing a pyridine nucleus fused to a saturated nitrogen-containing ring, including 7-azaoxindoles, 7-azaindolines, tetrahydro-[1,8]naphthyridines, and tetrahydro-5H-pyrido[2,3-b]azepin-8-ones, were prepared in good yield starting from various 2,6-dichloropyridines. The method hinges on a free-radical xanthate-mediated cyclization or intermolecular addition/cyclization sequence for the construction of the new fused rings.
Tin-Free Radical Cyclizations for the Synthesis of 7-Azaoxindoles, 7-Azaindolines, Tetrahydro[1,8]naphthyridines, and Tetrahydro-5H-pyrido[2,3-b]azepin-8-ones
摘要:
Compounds containing a pyridine nucleus fused to a saturated nitrogen-containing ring, including 7-azaoxindoles, 7-azaindolines, tetrahydro-[1,8]naphthyridines, and tetrahydro-5H-pyrido[2,3-b]azepin-8-ones, were prepared in good yield starting from various 2,6-dichloropyridines. The method hinges on a free-radical xanthate-mediated cyclization or intermolecular addition/cyclization sequence for the construction of the new fused rings.
An unprecedented radical ring closure on a pyridine nitrogen
作者:Myriem El Qacemi、Louis Ricard、Samir Z. Zard
DOI:10.1039/b609021d
日期:——
An unprecedented radical ring-closure onto the pyridine nitrogen was observed when certain types of substituents were present around the pyridine nucleus.
当某些类型的取代基存在于吡啶核周围时,观察到了前所未有的激进环闭合现象,发生在吡啶氮上。
O-Ethyl-S-(1,2,2,2-Tetrafluoroethyl)-Dithiocarbonate: A Convenient Reagent for the Generation and Capture of 1,2,2,2-Tetrafluoroethyl Radicals
作者:Samir Zard、David Clemente-Tejeda
DOI:10.1055/s-0035-1560539
日期:——
The synthesis of a new fluorinated reagent O-ethyl S-(1,2,2,2-tetrafluoroethyl) carbonodithioate (xanthate) and its use for the generation and capture of the hitherto unexplored 1,2,2,2-tetrafluoroethyl radicals is described. This reagent allows the convenient introduction of the rare CF3CHF motif onto various olefinic substrates with a high functional-group tolerance.
Tin-Free Radical Cyclizations for the Synthesis of 7-Azaoxindoles, 7-Azaindolines, Tetrahydro[1,8]naphthyridines, and Tetrahydro-5<i>H</i>-pyrido[2,3-<i>b</i>]azepin-8-ones
作者:Eric Bacqué、Myriem El Qacemi、Samir Z. Zard
DOI:10.1021/ol0489649
日期:2004.10.1
Compounds containing a pyridine nucleus fused to a saturated nitrogen-containing ring, including 7-azaoxindoles, 7-azaindolines, tetrahydro-[1,8]naphthyridines, and tetrahydro-5H-pyrido[2,3-b]azepin-8-ones, were prepared in good yield starting from various 2,6-dichloropyridines. The method hinges on a free-radical xanthate-mediated cyclization or intermolecular addition/cyclization sequence for the construction of the new fused rings.