Atom Economy: a Challenge for Enhanced Synthetic Efficiency

Abstract The sections in this article are Vinylidenes Cycloisomerization of Hydroxyalkynes Reconstitutive Condensation Redox Isomerization Allyl Alcohols Ruthenacyclopentadiene Intermediates Ruthenacyclopentene Intermediates Intermolecular Alkene‐Alkyne Coupling Butenolide Formation and Related Reactions Pyran Formation Intramolecular Alkene–Alkyne Coupling [5 + 2] Cycloaddition Vinyl Ketones as Alkyne Partners Allylic C – H Insertion Reactions of Alkenes Allene–Alkene Coupling Heterocycles via Allene–Alkene Coupling Conclusion Acknowledgments