Synthesis of Ynones and Recent Application in Transition-Metal-Catalyzed Reactions

alpha,beta-Acetylenic ketones (ynones) are found in important bioactive molecules and materials. They are also useful precursors to valuable heterocycles. In this review, methods of ynone preparation are described. Additionally, transition-metal-catalyzed methodologies utilizing ynones are introduced. Lastly, examples of these methodologies in the total synthesis of complex molecules are highlighted. Although they have been known for over 100 years, research over the past three decades has greatly expanded the understanding of ynone reactivity. This unique reactivity makes the ,-acetylenic ketone a useful moiety with untapped potential. 1 Introduction 2 Historical Perspective 3 Ynone Preparation 3.1 Distinct Metal Acetylides 3.2 Carbonylative Cross-Couplings 3.3 Oxidative Methods 4 Transition-Metal-Catalyzed Reactions of Ynones 4.1 Cyclizations 4.2 Miscellaneous Reactions 4.3 Ynones in Total Synthesis 5 Summary and Outlook