197173-25-4Relevant academic research and scientific papers
The preparation and intra- and intermolecular addition reactions of acyclic N-acylimines: Application to the synthesis of (±)-sertraline
DeNinno,Eller,Etienne
, p. 6988 - 6993 (2007/10/03)
Intramolecular endo-cyclization reactions of N-acyliminium ions have seen wide application for the synthesis of heterocyclic compounds. The corresponding exocyclic variant, which would provide 1-aminotetralin derivatives, for example, has little precedent. We have discovered that acyclic N-acylcarbamates can be readily reduced to the corresponding N-acylhemiaminal derivatives in high yield using DIBAL as the reducing agent. These intermediates are remarkably stable and, if desired, can be purified and stored. The acyclic N-acylhemiaminals undergo both intra- and intermolecular nucleophilic addition reactions mediated by strong Lewis acids, such as TiCl4. Diastereoselectivity, induced either by a substituent on the newly formed ring, or by utilizing a chiral ester on the carbamic acid, was disappointingly low. This methodology was successfully applied to the synthesis of the racemic form of the marketed antidepressant sertraline.
Efficient generation and intramolecular cyclization reactions of acyl imines
DeNinno, Michael P.,Eller, Cynthia
, p. 6545 - 6548 (2007/10/03)
Acyl carbamates can be selectively reduced with diisobutyl aluminum hydride to provide high yields of N-acyl hemiaminals 1. With appropriate substitution, these intermediates undergo Lewis acid catalyzed intramolecular exo cyclization reactions to afford
