Synthesis and Characterization of Functionally Substituted Cyclopentadienyl Derivatives of Silver and Copper

• Published in: Organometallics 2000-10, Vol.19 (20), p.4060-4065
• Main Authors: Lettko, Linda, Rausch, Marvin D
• Format: Article
• Language: English
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/om000618h

A series of functionally substituted cyclopentadienyl derivatives of silver and copper have been synthesized and characterized. Reactions between sodium acetyl- or carbomethoxycyclopentadienylide, triphenylphosphine, and silver triflate (AgSO3CF3) in DME produced Ag[C5H4C(O)CH3](PPh3) and Ag[C5H4CO2CH3](PPh3) in yields of 57−58%. Corresponding copper analogues were prepared using [BrCu(PPh3)]4. Similar reactions between sodium acetyl- or carbomethoxycyclopentadienylide and AgSO3CF3 in the presence of the bidentate ligand 1,2-bis(diphenylphosphino)ethane afforded the chelated compounds Ag[C5H4C(O)CH3][Ph2P(CH2)2PPh2] and Ag[C5H4CO2CH3][Ph2P(CH2)2PPh2] in 55−72% yields. Dinuclear compounds of the type [Ag(C5H4PPh2)(PR3)]2 (R = Ph, Et) resulted in 36−49% yield from reactions of silver chloride with the appropriate phosphine in refluxing toluene, followed by cooling to −78 °C and subsequent reactions with lithium diphenylphosphinocyclopentadienide. The compounds M(C5Ph5)(PEt3) (M = Ag, Cu) containing five bulky phenyl substituents were obtained in 44−56% yield from reactions of sodium pentaphenylcyclopentadienide and [ClM(PEt3)]4 in THF. In general, the new organosilver compounds containing functional substituents on the cyclopentadienyl ring as well as binuclear phosphine derivatives exhibited enhanced thermal and oxidative stabilities compared with the parent compound Ag(C5H5)(PPh3). 31P NMR studies of the compounds have been undertaken and are in agreement with the proposed structures.