Synthesis and reactivity of functionalized rhenium germyl complexes (η5-C5H5)Re(NO)(PPh3)(GePh2X); dynamic equilibria with germylene complex [(η5-C5H5)Re(NO)(PPh3)(GePh2)]+X− Academic Article uri icon

abstract

  • Reaction of Li+[(η5-C5H5)Re(NO)(PPh3)]- with Ph3GeCl and Ph2GeCl2 (THF, -75°C) gives germyl complexes (η5-C5H5)Re(NO)(PPh3)(GePh3) (84%) and (η5-C5H5) Re(NO)(PPh3)(GePh2Cl) (3, 82%), respectively. Reaction of 3 and (CH3)3SiOTf gives (η5-C5H5)Re(NO)(PPh3)(GePh2OTf) (4, 82%). Several properties show the triflate substituent in 4 to be extremely labile. First, reaction of 4 and pyridine to give [(η5- C5H5)Re(NO)(PPh3)(GePh2NC5H5)]+TfO- (5) is complete in < 5 min at -78°C; the pyridine in 5 rapidly exchanges with pyridine-d5 (CD2Cl2, -80°C). Second, the 13C NMR resonances of the diastereotopic germanium phenyl substituents in 4 coalesce upon warming (ΔG‡268K (CD2Cl2) = 12.6±0.2 kcal mol-1). The most likely mechanisms for this dynamic behaviour entail initial triflate dissociation to give the germylene complex [(η5-C5H5)Re(NO)(PPh3)( GePh2)]+TfO-. © 1988.

author list (cited authors)

  • Lee, K. E., & Gladysz, J. A.

citation count

  • 5

publication date

  • January 1988