Amphiphilic ruthenium benzylidene metathesis catalyst with PEG-substituted pyridine ligands

Synthesis of a ruthenium benzylidene metathesis catalyst made amphiphilic by coordination of the ruthenium center with PEG-substituted by coordination of the ruthenium center with PEG-substituted pyridine ligands was investigated. 4-Hydroxypyridine was passed through a plug of neutral alumina, precipitated into diethyl, filtered and dried in vacuo. The presence of the chain-end hydroxyl group of compound provided water solubility that was not observed in the methyl ether terminated analogs. Rsults show that the catalyst represents a unique combination of the enhanced reactivity given by the N-heterocyclic carbene ligand and the amphiphilicity imparted by PEGylation.