Ruthenium‐Induced Cyclization of Heteroatom‐Functionalized Alkynes: Progress, Challenges and Perspectives
Lai‐Hon Chung, Chi‐Fung Yeung, Chun‐Yuen Wong
Abstract
Abstract Metal‐induced cyclization of functionalized alkynes represents one of the most general approaches to prepare organic heterocycles. Although Ru II centers are well‐established to promote alkyne to vinylidene rearrangements and many Ru II ‐mediated alkyne cyclizations have been rationalized to be the results of post‐vinylidene transformations, recent discoveries indicate that Ru II centers can serve as electrophiles and induce alkyne cyclizations without vinylidene intermediacy. In this Minireview, an overview of the Ru II ‐induced cyclization of heteroatom‐functionalized alkynes in the last decade is provided, with an emphasis on the discoveries and validations of the unconventional “non‐vinylidene‐involving” pathways.