Reactions of hexacarbonylrhenium(I) perchlorate with phosphines and other ligands

Abstract

Hexacarbonylrhenium perchlorate, [Re(CO)6]ClO4, reacts on heating above 120° with 1,2-bis(diphenylphosphino)ethane and with triphenylphosphine to form respectively [Re(CO)4(Ph2C2H4PPh2)]ClO4 and trans-Re(CO)3(PPh3)2Cl. The stereochemistry of trans-Re(CO)3(PPh3)2Cl was established by dipole moment and infrared measurements. Other phosphines failed to yield clean products. The reactions of phosphines and other ligands with [Re(CO)6]ClO4 are discussed, in particular the reaction with triphenylphosphine in which the perchlorate is reduced to chloride and incorporated by rhenium to form trans-Re(CO)3(PPh3)2Cl.