The role of the pyridyl group in this catalytic cycle is evident when the ligand is replaced by triphenyl phosphine, and rates of catalysis a greatly decreased.
en.wikipedia.org The bridging carbon of the norbornene ring is double bonded to a carbon atom to which a pyridyl and a phenyl group are attached.
en.wikipedia.org Possible substrate scope includes thienyl, pyridyl, furyl, and benzofuranyl, 1-naphthyl, and aryl groups with either electron-donating or electron-withdrawing substituent.
en.wikipedia.org One of the carbon atoms of this double bond is connected to another carbon atom, that is bound to a hydroxyl, a pyridyl and a phenyl group.
en.wikipedia.org When neutralized, the noncoordinated pyridyl groups are found to catalyze transesterification reactions, presumably by facilitating deprotonation of the reactant alcohol.
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