Anion Metathesis in Facile Preparation of Olefin Metathesis Catalysts Bearing a Quaternary Ammonium Chloride Tag

Easy and efficient method for preparation of all-chloro ruthenium catalysts bearing a quaternary ammonium tag was developed. The key anion metathesis reaction was made with AgCl, and the facile recycling of silver wastes was demonstrated. The developed method transforms more accessible, yet poorly characterised mixed chloro/iodo Ru complexes into valuable all-chloro catalysts, useful in aqueous metathesis. Practical utility of the developed anion metathesis reaction was demonstrated by preparation of a commercial Ru catalyst, StickyCat™, on a 5 gram scale.