Reactivity Studies of (Phenylethynyl)germylene LGeCCPh (L = HC[C(Me)N-2,6-iPr2C6H3]2) toward Pentafluorophenylcopper(I), -silver(I), and -gold(I) Complexes

Reactions of (phenylethynyl)germylene LGeC CPh (L = HC[C(Me)N-2,6-iPr(2)C(6)H(3)](2)) with 0.25 equiv of (CuC6F5)(4), 1 equiv of AgC6F5.MeCN, and 1 equiv of AuC6F5 center dot SC4H8, respectively, yielded LGe(Ca CPh)CuC6F5 (1), [(LGeC CPh)(2)Ag](+)[Ag(C6F5)(2)](-) (2), and LGe(C CPh)AuC6F5 (3). Complexes 1-3 were characterized by IR and NMR spectroscopy and X-ray crystallography. Compound 1 shows a bonding pattern of the CuC6F5 entity by both the phenylethynyl C C linkage and the L ligand backbone of the gamma-C atom, while 3 exhibits a bonding mode of the AuC6F5 entity at the germylene center. Compound 2 is an ionic derivative featuring the Ge-Ag donor acceptor bond formed under redistribution of the AgC6F5 entity. Further reactions of 1 with (CuC6F5)4, AgC6F5.MeCN, and AuC6F5 center dot SC4H8 afforded the complexes LGe(CEECPh)(CuC6F5)(MC6F5) (M = Cu (4), Ag (5), Au (6)). Compounds 4-6 were characterized by IR and NMR spectroscopy, and 5 and 6 were further investigated by X-ray crystallography. Compounds 4-6 all show an additional bonding of the respective MC6F5 moiety at the germylene center of 1. These studies reveal a multiple donor reactivity of LGeC CPh. The slightly different Lewis acidic properties of the congeneric pentafluorophenylcopper(I), -silver(I), and -gold(I) complexes as acceptors are thus disclosed.