New catalyst design for polymerization of norbornene esters by reducing intramolecular interaction.
We have used density functional theory to study palladium-based catalysts commonly used for the polymerization of norbornene derivatives with an ester group. Exo-exo, exo-endo, and endo-endo isomers of catalyst complexes were investigated; the endo-endo isomer was the most stable and inactive due to an intramolecular interaction between Pd and O of the carbonyl group. Phosphine groups are effective in minimizing the Pd-O interaction in the endo-endo isomer and P(C6H11)3 was found to be the most efficient reagent. The intramolecular Pd-O interactions were estimated using model complexes, and it was demonstrated that they play a crucial role in stabilizing the endo-endo isomer.
Kim
Kyoung Hoon
KH
Corporate R&D, LG Chem. Ltd., Research Park, 305-380 Daejon, South Korea. michaol@lgchem.com
Han
Young-Kyu
YK
Lee
Sang Uuk
SU
Chun
Sung-Ho
SH
Ok
Jong Hoa
JH
D001643:Bridged Bicyclo Compounds / Q000737:chemistry*; D002384:Catalysis; D015195:Drug Design; D004952:Esters / Q000737:chemistry*; D007536:Isomerism; D008745:Methylation; D008968:Molecular Conformation; D011108:Polymers / Q000737:chemistry*
D001643:Bridged Bicyclo Compounds; D004952:Esters; D011108:Polymers