A highly efficient olefin metathesis initiator: improved synthesis and reactivity studies

The synthesis of ligand 8, required for the preparation of catalyst 4c has been optimised. Ligand exchange studies indicate that biphenyl-based alkylidene 4c initiates considerably faster than its unsubstituted analogue 4a. The performance of 4c in ring-opening cross metathesis reactions involving substrates containing unprotected chelating atoms is also reported.