chelating ligand precursors for the preparation of olefin methathesis catalysts are disclosed . the resulting catalysts are air stable monomeric species capable of promoting various methathesis reactions efficiently , which can be recovered from the reaction mixture and reused . internal olefin compounds , specifically beta - substituted styrenes , are used as ligand precursors . compared to terminal olefin compounds such as unsubstituted styrenes , the beta - substituted styrenes are easier and less costly to prepare , and more stable since they are less prone to spontaneous polymerization . methods of preparing chelating - carbene methathesis catalysts without the use of cucl are disclosed . this eliminates the need for cucl by replacing it with organic acids , mineral acids , mild oxidants or even water , resulting in high yields of hoveyda - type methathesis catalysts . the invention provides an efficient method for preparing chelating - carbene metathesis catalysts by reacting a suitable ruthenium complex in high concentrations of the ligand precursors followed by crystallization from an organic solvent .