biostudies-literatureUnknown13(41)Cherif SEOlefin cross-metathesis is a cornerstone reaction in organic synthesis where stereoselectivity is typically governed by the structure of the catalyst. In this work, we show that merging Grubbs second generation catalyst, a classical <i>E</i>-selective catalyst, with a readily available photocatalyst, enables the exclusive formation of the contra-thermodynamic <i>Z</i>-isomer. The scope and limitations of this unprecedented approach are discussed based on both computational and experimental mechanistic data.Chemical science12065-12070https://www.ebi.ac.uk/biostudies/studies/S-EPMC9600307biostudies-literatureMerging Grubbs second-generation catalyst with photocatalysis enables <i>Z</i>-selective metathesis of olefins: scope, limitations, and mechanism.PMC9600307Ghosh ADixon IMLakhdar SCherif SEChelli SKraiem JfalseMerging Grubbs second-generation catalyst with photocatalysis enables <i>Z</i>-selective metathesis of olefins: scope, limitations, and mechanism.Olefin cross-metathesis is a cornerstone reaction in organic synthesis where stereoselectivity is typically governed by the structure of the catalyst. In this work, we show that merging Grubbs second generation catalyst, a classical <i>E</i>-selective catalyst, with a readily available photocatalyst, enables the exclusive formation of the contra-thermodynamic <i>Z</i>-isomer. The scope and limitations of this unprecedented approach are discussed based on both computational and experimental mechanistic data.2022-01-01T00:00:00Z2022 Oct2025-04-22T21:12:40.039Z2025-04-06T03:30:10.631ZS-EPMC96003073634910410.1039/d2sc03961c