1,2-Addition <i>versus</i> homoconjugate addition reactions of indoles and electron-rich arenes to α-cyclopropyl <i>N</i>-acyliminium ions: synthetic and computational studies
作者:Greg M. Ryder、Uta Wille、Anthony C. Willis、Stephen G. Pyne
DOI:10.1039/c9ob01363f
日期:——
of these reactions, clearly showing that the 1,2-addition pathway is kinetically controlled. In reactions where the 1,2-adduct is destabilised, for example when the arene ring is less nucleophilic, the 1,2-addition is reversible and the thermodynamically preferred homoconjugate addition and subsequent rearrangement and cyclisation reactions become the major pathway.
Synthesis of spirocyclic heterocycles from α,β-unsaturated <i>N</i>-acyliminium ions
作者:Thanphat Thaima、Arife Yazici、Chiramet Auranwiwat、Anthony C. Willis、Uta Wille、Thunwadee Limtharakul、Stephen. G. Pyne
DOI:10.1039/d0ob02075c
日期:——
The reactions of α,β-unsaturated N-acyliminium ions, generated in situ from 4(S)-O-substitutedhydroxy-5-hydroxy-5-vinyl-N-alkylpyrrolidin-2-ones, with allylsilanes and indoles leading to the formation of spirocyclic heterocycles, are reported. Six single crystal X-ray structures and extensive 2D NMR experiments confirmed the structures and stereochemistries of these products. In addition, computational