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Unique α-hemiaminal ether gold carbene intermediates were accessed by a gold-catalysed 1,1-carboalkoxylation strategy and evolved through a highly selective 1,2-N-migration. This skeletal rearrangement gave functionalised indenes, and isotopic labelling confirmed the rare C-N bond cleavage of the ynamide moiety. The effect of substituents on the migration has been explored, and a model is proposed to rationalise the observed selectivity., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Gold carbene reactivity patterns were accessed by ynamide insertion into a C(sp3)-H bond. A substantial increase in molecular complexity occurred through the cascade polycyclization of N-allyl ynamides to form fused nitrogen-heterocycle scaffolds. Exquisite selectivity was observed despite several competing pathways in an efficient gold-catalyzed synthesis of densely functionalized C(sp3)-rich polycycles and a copper-catalyzed synthesis of fused pyridine derivatives. The respective gold–keteniminium and ketenimine activation pathways have been explored through a structure–reactivity study, and isotopic labeling identified turnover-limiting C-H bond-cleavage in both processes. [ABSTRACT FROM AUTHOR]

Unique α-hemiaminal ether gold carbene intermediates were accessed by a gold-catalysed 1,1-carboalkoxylation strategy and evolved through a highly selective 1,2- N-migration. This skeletal rearrangement gave functionalised indenes, and isotopic labelling confirmed the rare CN bond cleavage of the ynamide moiety. The effect of substituents on the migration has been explored, and a model is proposed to rationalise the observed selectivity. [ABSTRACT FROM AUTHOR]

The rapidly expanding field of gold and platinum π-acid catalysis has led to the discovery of diverse transformations that are initiated with nucleophilic attack onto a metal-activated alkyne. This review brings together those reactions which employ a heteroatom nucleophile bearing a functional group that can subsequently migrate to effect a formal insertion of the alkyne into a carbon- heteroatom σ-bond. This reactivity profile is encountered in a range of efficient and powerful cycloisomerisations for the preparation of carbo- and heterocycles. 1 Introduction 2 1,2-Addition of Carbon-Heteroatom Bonds across Alkynes 2.1 Heteroatom-to-Carbon Allyl Migrations 2.2 Accessing Sigmatropic Rearrangements 2.3 Related Palladium-Catalysed 1,2-Carboalkoxylations and Carboaminations 2.4 Beyond Allyl Migration in the 1,2-Carbofunctionalisation of Alkynes 2.5 Oxonium Ion Migration 2.6 Migrating Centres at Higher Oxidation Levels 2.7 Migration of Heteroatoms 3 1,5 Heteroatom-to-Carbon Migrations 3.1 Alkynyl Benzoates as Alkylating Agents 4 Internal versus External Migrations 4.1 Internal Migrations of Oxonium Species 5 1,1-Carbofunctionalisations 6 Application in Natural Products 7 Summary and Conclusions [ABSTRACT FROM AUTHOR]