1108697-82-0Relevant academic research and scientific papers
Piperidines from acid-catalysed cyclisations: Pitfalls, solutions and a new ring contraction to pyrrolidines
Aldmairi, Abdul H.,Griffiths-Jones, Charlotte,Dupauw, Alexis,Henderson, Laura,Knight, David W.
, p. 3690 - 3694 (2017/09/02)
The success of acid-catalysed cyclisations of alka-4-enylamine derivatives to piperidines depends very much on the nature of the amine protecting group: while carbamates and related amides can usually be readily and cleanly transformed, the corresponding sulfonamides react further by ring contraction leading to pyrrolidines, especially when such substrates are sterically crowded.
Aminopyridinato titanium catalysts for the hydroaminoalkylation of alkenes and styrenes
Doerfler, Jaika,Doye, Sven
supporting information, p. 1806 - 1809 (2013/04/10)
The linear product is formed as the major product when in situ generated titanium complexes with aminopyridinato ligands are used as catalysts for hydroaminoalkylation reactions of styrenes (see scheme). The reaction is not limited to the use of N-methyla
Gold- and silver-catalyzed tandem amination/ring expansion of cyclopropyl methanols with sulfonamides as an expedient route to pyrrolidines
Rao, Weidong,Chan, Philip Wai Hong
experimental part, p. 10486 - 10495 (2009/10/15)
An efficient synthetic route to pyrrolidines that relies on AuCl/ AgOTf-catalyzed tandem amination/ ring expansion of substituted cyclopropyl methanols with sulfonamides is reported herein. The reactions proceed rapidly at 100 °C with catalyst loadings as low as 2 mol % and produce the pyrrolidine products in yields of 30-95%. The method was shown to be applica ble to a broad range of cyclopropyl methanols, including unactivated ones, and sulfonamide substrates containing electron-withdrawing, electron-donating, and sterically-demanding substitu ents. The mechanism is suggested to involve activation of the alcohol substrate by the AuCl/AgOTf catalyst, followed by ionization of the starting material, which causes ring opening of the cyclopropane moiety and trapping by the sulfonamide nucleophile. The resultant aminated acyclic intermediate undergoes subsequent intramolecular hydroamination to give the pyrrolidine.
