Advances and challenges in user-friendly alkyne metathesis catalysts

Alkyne metathesis (AM), the cousin of the 'noble' alkene metathesis, has attracted rapidly growing attention within the past 20 years and has been widely used in the synthesis of natural products, functional polymers, and shapepersistent molecular architectures. Given some excellent reviews in recent years, this article will not provide a comprehensive review of the catalyst development and the wide applications of AM, but rather will focus on the rational design of the catalysts, substrate structures, and reaction conditions that meet the requirements of certain metathesis pathways (e.g., cyclooligomerization, polymerization, self-correction) and will make the catalytic systems more userfriendly and practically useful (e.g., operating in air and with long lifetimes and broad substrate scope).