Synthesis of highly functionalised spiro-indoles by a halogen atom transfer radical cyclization
作者:Christian V. Stevens、Ellen Van Meenen、Yves Eeckhout、Bart Vanderhoydonck、Wim Hooghe
DOI:10.1039/b508424e
日期:——
The halogen atom transfer radical cyclization (HATRC) has been evaluated on N-(indolylmethyl)trichloroacetamides under Cu(I)Cl catalysis using nitrogen containing ligands. The ring closure leads to the formation of 3,3-spiro-3H-indoles in moderate to good yields by a 5-exo-mechanism. Derivatives with an N-electron withdrawing substituent also lead to a 5-exo-trig and not to a 6-endo-trig cyclization.
卤素原子转移自由基环化反应(HATRC)在含氮配体的存在下,通过Cu(I)Cl催化作用,对N-(吲哚甲基)三氯乙酰胺进行了评估。环化反应通过5-exo机制进行,形成了中等至良好产率的3,3-螺-3H-吲哚。具有吸电子N取代基的衍生物也导致5-exo-trig环化而非6-endo-trig环化。