AUTHOR=Weber Sebastian M. , Hilt Gerhard 

TITLE=Late 3d Metal-Catalyzed (Cross-) Dimerization of Terminal and Internal Alkynes

JOURNAL=Frontiers in Chemistry

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2021.635826

DOI=10.3389/fchem.2021.635826

ISSN=2296-2646

ABSTRACT=<p>This review will outline the recent advances in chemo-, regio-, and stereoselective (cross-) dimerization of terminal alkynes to generate 1,3-enynes using different types of iron and cobalt catalysts with altering oxidation states of the active species. In general, the used ligands have a crucial effect on the stereoselectivity of the reaction; e.g., bidentate phosphine ligands in cobalt catalysts can generate the <italic>E</italic>-configured <italic>head-to-head</italic> dimerization product, while tridentate phosphine ligands can generate either the <italic>Z</italic>-configured <italic>head-to-head</italic> dimerization product or the branched <italic>head-to-tail</italic> isomer. Furthermore, the hydroalkynylation of silyl-substituted acetylenes as donors to internal alkynes as acceptors will be discussed using cobalt and nickel catalysts.</p>