Cross-enyne and ring-closing metathesis cascade: A building-block approach suitable for diversity-oriented synthesis of densely functionalized macroheterocycles with amino acid scaffolds

Abstract

Suitably functionalized glycine derivatives undergo a cross-enyne and ring-closing metathesis cascade to generate macroheterocyclic ring systems in good yield. These macrocycles, prepared on the basis of a fragment coupling strategy, consist of 13-16-membered rings. To this end, 1,5-hexadiene was found to be a promising cross-coupling partner to generate macrocycles by this tandem metathesis sequence. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)