Diverse<i>N</i>-Heterocyclic Ring Systems via Aza-Heck Cyclizations of<i>N</i>-(Pentafluorobenzoyloxy)sulfonamides
作者:Ian R. Hazelden、Xiaofeng Ma、Thomas Langer、John F. Bower
DOI:10.1002/anie.201605152
日期:2016.9.5
bond of N‐(pentafluoro‐benzoyloxy)sulfonamides are described. These studies, which encompass only the second class of aza‐Heck reaction developed to date, provide direct access to diverse N‐heterocyclicringsystems.
Stereospecific Alkene Aziridination Using a Bifunctional Amino-Reagent: An Aza-Prilezhaev Reaction
作者:Joshua J. Farndon、Tom A. Young、John F. Bower
DOI:10.1021/jacs.8b10485
日期:2018.12.26
deprotection (TFA) of O-Ts activated N-Boc hydroxylamines triggers intramolecular aziridination of N-tethered alkenes to provide complex N-heterocyclic ring systems. Synthetic and computational studies corroborate a diastereospecific aza-Prilezhaev-type mechanism. The feasibility of related intermolecular alkene aziridinations is also demonstrated.
Enantioselective Aza-Heck Cyclizations of <i>N</i>-(Tosyloxy)carbamates: Synthesis of Pyrrolidines and Piperidines
作者:Xiaofeng Ma、Ian R. Hazelden、Thomas Langer、Rachel H. Munday、John F. Bower
DOI:10.1021/jacs.8b12689
日期:2019.2.27
Pd(0)-systems modified with SPINOL-derived phosphoramidate ligands promote highly enantioselective aza-Heck cyclizations of alkenyl N-(tosyloxy)carbamates. The method provides versatile access to challenging N-heterocycles and represents the broadest scope enantioselective aza-Heck protocol developed to date.
A Rh(III)‐catalyzed Csp2−Csp3 bondcleavage/carbonylethylation of α‐indolylalcohols with allylic alcohols has been reported. This transformation involved a cascade C−C bondcleavage/C−C bond formation, and provides a novel approach to assemble 2‐carbonylethylindole skeletons.
Pyrrolidines and Piperidines by Ligand-Enabled Aza-Heck Cyclizations and Cascades of <i>N</i>
-(Pentafluorobenzoyloxy)carbamates
作者:Ian R. Hazelden、Rafaela C. Carmona、Thomas Langer、Paul G. Pringle、John F. Bower
DOI:10.1002/anie.201801109
日期:2018.4.23
Ligand‐enabled aza‐Heck cyclizations and cascades of N‐(pentafluorobenzoyloxy)carbamates are described. These studies encompass the first examples of efficient non‐biased 6‐exo aza‐Heck cyclizations. The methodology provides direct and flexible access to carbamate protected pyrrolidines and piperidines.