Aryl Grignard Reagents in Chemodivergent N- and C-Arylations: Concise Access to Two Families of Tetracyclic Fused Carbazoles from 6-Nitroquinolines
作者:Juan Domingo Sánchez、Riccardo Egris、Subbu Perumal、Mercedes Villacampa、J. Carlos Menéndez
DOI:10.1002/ejoc.201101848
日期:2012.4
The reaction between aryl Grignard compounds and 5-methoxy-6-nitroquinoline derivatives in THF was found to proceed in a chemodivergent mode that depended on the functional groups present in the heterocyclic ring. Thus, the reactions that started from carbostyril derivatives afforded 6-(arylamino)carbostyrils as the major products, whereas those that started with 2-alkoxyquinolines gave exclusively
发现芳基格氏化合物和 5-甲氧基-6-硝基喹啉衍生物在 THF 中的反应以依赖于杂环中存在的官能团的化学发散模式进行。因此,从喹诺酮衍生物开始的反应提供了 6-(芳基氨基)喹啉作为主要产物,而那些以 2-烷氧基喹啉开始的反应只得到了 5-芳基喹啉。两种类型的产物分别通过钯促进的氧化偶联或卡多根反应转化为四环稠合线性或角咔唑体系。在这项工作的过程中,发现了一种前所未有的醋酸钯氧化脱甲基反应,将 1,4-二甲氧基苯系统氧化为相应的醌类。