The present invention provides unimolecular metal complexes having increased activity in the copolymerization of carbon dioxide and epoxides. Also provided are methods of using such metal complexes in the synthesis of polymers. According to one aspect, the present invention provides metal complexes comprising an activating species with co-catalytic activity tethered to a multidentate ligand that is coordinated to the active metal center of the complex.
The present invention describes metal salen complexes having dianionic counterions. Such complexes can be readily precipitated and provide an economical method for the purification and isolation of the complexes, and are useful to prepare novel polymer compositions.
CATALYSTS FOR EPOXIDE CARBONYLATION
申请人:Novomer, Inc.
公开号:US20170080409A1
公开(公告)日:2017-03-23
The present invention encompasses catalysts for the carbonylation of heterocycles such as ethylene oxide, as well as methods for their use. The catalysts feature Lewis acidic metal complexes having one or more tethered metal-coordinating groups in combination with at least one metal carbonyl species. In preferred embodiments, the inventive catalysts have improved stability when subjected to product separation conditions in continuous ethylene oxide carbonylation processes.