An I2-mediated synthesis of phenanthridines via intramolecular sp3 C-H amination of readily accessible aniline precursors is reported. The present synthetic process is straightforward and applicable to a broad variety of unprotected aniline substrates, and provides facile and efficient access to phenanthridine derivatives. This C-H amination protocol does not use transition metals, is operationally
Functionalized 4-benzylated pyridines can be efficiently prepared by a transition-metal-freecross-coupling between various benzylic zinc chlorides and substituted 4-cyanopyridines in THF/DMPU under microwave irradiation (40 °C, 0.5–1.5 h). Selective benzylations on polycyano-aromatics have also been achieved under these mild conditions. We also report a novel oxidative nucleophilic substitution of
Coupling N–H Deprotonation, C–H Activation, and Oxidation: Metal-Free C(sp<sup>3</sup>)–H Aminations with Unprotected Anilines
作者:Christopher J. Evoniuk、Gabriel dos Passos Gomes、Sean P. Hill、Satoshi Fujita、Kenneth Hanson、Igor V. Alabugin
DOI:10.1021/jacs.7b07519
日期:2017.11.15
An intramolecular oxidativeC(sp3)–H amination from unprotected anilines and C(sp3)–H bonds readily occurs under mild conditions using t-BuOK, molecular oxygen and N,N-dimethylformamide (DMF). Success of this process, which requires mildly acidic N–H bonds and an activated C(sp3)–H bond (BDE < 85 kcal/mol), stems from synergy between basic, radical, and oxidizing species working together to promote