Synthetic Strategy for Cyclic Amines: A Stereodefined Cyclic N,O‐Acetal as a Stereocontrol and Diversity‐Generating Element

Abstract

Ringbildung: Eine neue Strategie zur Synthese cyclischer Amine nutzt ein stereochemisch definiertes cyclisches N,O‐Acetal als wichtigstes stereokontrollierendes und Diversität erzeugendes Element. Das Acetal, das seine stereochemische Integrität über alle katalytischen Umwandlungen bewahrt, wurde durch asymmetrische Hydroaminierung eines Alkoxyallens mit dem chiralen Liganden L* und anschließende Ringschlussmetathese erhalten.

Metal-Catalyzed Intermolecular Hydrofunctionalization of Allenes: Easy Access to Allylic Structures via the Selective Formation of C–N, C–C, and C–O Bonds

“…The enantiomeric control was also performed few month later with achiral nitrogen-containing partner, using the same catalytic system. 78,79 Scheme 24: Stereoselective hydroamidation of allenyl ethers with sulfonamides catalyzed by Pd.…”

Access to trans‐3,4‐Dihydroxy‐2‐alkylpyrrolidines and Piperidines by Use of Stereodefined Cyclic N,O‐Acetals as a Diversity‐Generating Element

“…With regard to the stereoselectivity of the Lewis acid‐mediated carbon–carbon bond formation step, cis stereochemistry between C 2 and C 3 substituents was observed when the hydroxyl groups were protected with tert ‐butyldimethylsilyl (TBDMS) group 1a. From the viewpoint of controlling stereochemical diversity of the cyclic amine structure, we became interested in developing a synthetic method to generate diastereomeric trans‐ 3,4‐dihydroxy‐2‐alkyl‐pyrrolidines and piperidines 2.…”