Publications by authors named "Carolin Welter"

The synthesis of nicotine with enantiomeric excess of >99% ee was accomplished by asymmetric Ir-catalysed allylic amination followed by ring closing metathesis and racemization-free double bond reduction.

View Article and Find Full Text PDF

Carbocycles with > 90% ee were prepared via Ir-catalysed asymmetric allylic alkylation/ring closing metathesis sequences or enantioselective Ir-catalysed intramolecular allylic alkylations.

View Article and Find Full Text PDF

[reaction: see text] Enantioselective Ir-catalyzed intramolecular allylic aminations and etherifications are described. Up to 97% ee was achieved using catalysts prepared by in situ activation of mixtures of phosphorus amidites and [Ir(COD)Cl]2. Sequential aminations of bis-allylic carbonates, involving an inter- followed by an intramolecular reaction, gave trans-N-benzyl-2,5-divinylpyrrolidine and trans-N-benzyl-2,6-divinylpiperidine with > or = 99% ee.

View Article and Find Full Text PDF

Enantioselective iridium-catalysed intramolecular allylic aminations, using phosphinooxazolines or phosphorus amidites as ligands, provided ee values of >90%, at a catalyst loading of <0.5 mol-%, and displayed a marked preference for intra- over corresponding intermolecular reactions.

View Article and Find Full Text PDF