High activity metal carbene metathesis catalysts generated using a thermally activated N-heterocyclic carbene precursor

摘要

The invention provides a method for converting a less active or slower to initiate system to a higher activity system so that at the end of a polymerization the most active species is present in the system. The invention generally relates to a process for converting a less active or slower to initiate catalyst system to a higher activity catalyst system wherein the process comprises contacting a protected N-heterocyclic carbene with a metathesis catalyst and an olefin in the presence of energy. One of the benefits of the invention is that the amount of catalyst required is less than or lowered in the presence of the protected N-heterocyclic carbene as compared to the amount of catalyst required in the absence of the protected N-heterocyclic carbene. The protected N-heterocyclic carbene can be unsaturated or saturated. In addition, the invention describes novel ruthenium initiators and methods of making the same.