Carbonyl ligand substitution of an aminerhenium benzyl complex. Interconversion of eta 1- and eta 3-benzyl complexes

摘要

Removal of a CO ligand from the eta(1)-benzyl. complex [Re(CO)(2)(eta(1)-CH2Ph){NH(Me)CH2CH2(eta(5)-C5H4)}](+) Br- yielded an eta(3)-benzyl complex. The eta(3) co-ordination mode was converted into eta(1) when the compound was dissolved in acetonitrile. Evaporation of acetonitrile removed the labile acetonitrile ligand and regenerated the eta(3)-benzyl complex. The eta(3)-benzyl complex [Re(CO)(eta(3)-CH2Ph){NH(Me)CH2CH2(eta(5)-C5H5)}](+) BF4- is stable to air and moisture. The corresponding perrhenate salt has been characterized crystallographically. The tetrafluoroborate reacted with bromide, chloride and acetate anion to give the corresponding neutral eta(1)-benzyl complexes in excellent yield. When treated with two-electron donor ligands, such as tert-butyl isocyanide and pyridine, it was converted into the corresponding (eta(1)-benzyl)(isocyanide) and pyridine complexes. [References: 24]