Ring-closing metathesis reaction Hoveyda-Grubbs catalyst

Y. Kobayoshi, S. Inukai, T. Watanabe, Y. Sogiyama, H. Hamamoto, T. Shioiri, M. Matsugi, A medium fluorous Grubbs-Hoveyda 2nd generation catalyst for phase transfer catalysis of ring closing metathesis reactions. Tet. Lett. 56(11), 1363-1366 (2015)... 

Barbasiewicz et al. [99] reported on the Hoveyda-Grubbs metathesis catalyst bearing a chelating benzylidene ligand assembled on / en -substituted naphthalene 8.68, as shown in Eq. (8.22). In contrast to usual naphthalene-based compounds 8.67, it exhibits a very fast initiation behavior for a ring-closing metathesis reaction (Eq. (8.22)), which is attributed to a distorted molecular structure and reduced i-electron delocalization within a weakly stabilized six-membered chelate ring. 

In 2012, You and co-workers developed a cascade ring-closing metathesis/ isomerization/asymmetric Pictet-Spengler reaction, employing ruthenium complex (Hoveyda-Grubbs II catalyst) and chiral phosphoric acid as the... 

A synthesis of enantioenriched tetrahydro- -carbolines has been reported using chiral phosphoric acid in conjunction with Hoveyda-Grubbs II catalyst through a ring-closing metathesis/isomerization/Pictet-Spengler cascade reaction (Scheme 93). ... 

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