Light- and Thermal-Activated Olefin Metathesis of Hindered Substrates

Efficient
light- and thermal-activated metathesis reactions of
tetra-substituted olefins were obtained by the S-chelated ruthenium
precatalyst Tol-SCF3. Its reactivity
in a series of benchmark olefin metathesis reactions was compared
to previously reported Mes-SCF3 and a novel sterically congested S-chelated complex, Dipp-SCF3. Tol-SCF3 is thus the first latent catalyst proven to be capable of
promoting olefin metathesis of demanding substrates upon light stimulation
at room temperature.