N-Methylation of Aromatic Amines and N-Heterocycles under Acidic Conditions with the TTT (1,3,5-Trioxane–Triethylsilane–Trifluoroacetic Acid) System
作者:Franz Bracher、Tobias Popp
DOI:10.1055/s-0034-1381049
日期:——
specific for aromatic amines and several N-heterocycles (indoles and annulated analogues, phenoxazine, phenothiazine), insensitive to steric hindrance, and compatible with a wide range of functional groups. Further the N-methylation step can be combined with an in situ N-Boc deprotection. Compounds in which the nucleophilicity of the NH group is eliminated by protonation under the reaction conditions (aliphatic
摘要 公开了在酸性条件下用TTT(1,3,5-三恶烷-三乙基硅烷-三氟乙酸)体系的新型还原性N-甲基化方案。该方法对芳族胺和几种N-杂环(吲哚和环状类似物,吩恶嗪,吩噻嗪)高度专一,对空间位阻不敏感,并且与多种官能团兼容。另外,N-甲基化步骤可以与原位N- Boc脱保护结合。在反应条件下通过质子化消除了NH基团亲核性的化合物(脂族胺,值得注意的碱性氮杂芳烃)是惰性的。在几个例子中,证明了TTT系统与其他N-甲基化方案是互补的。 公开了在酸性条件下用TTT(1,3,5-三恶烷-三乙基硅烷-三氟乙酸)体系的新型还原性N-甲基化方案。该方法对芳族胺和几种N-杂环(吲哚和环状类似物,吩恶嗪,吩噻嗪)高度专一,对空间位阻不敏感,并且与多种官能团兼容。另外,N-甲基化步骤可以与原位N- Boc脱保护结合。在反应条件下通过质子化消除了NH基团亲核性的化合物(脂族胺,值得注意的碱性氮杂芳烃)是惰性的。在几