Gold(III) adducts of 2-vinyl- and 2-ethylpyridine and cyclometallated derivatives of 2-vinylpyridine: Crystal structure of the cyclometallated derivative [Au( k2- C,N–CH 2CH(Cl)–C 5H 4N)(PPh 3)Cl][PF 6

Abstract

Reaction of Na[AuCl 4] with 2-vinylpyridine (vinpy) and 2-ethylpyridine (etpy) affords the N-bonded adducts Au(Rpy)Cl 3 (R = CH 2 CH, vinpy; CH 3CH 2, etpy). Cationic adducts, [Au(vinpy) 2Cl][X] 2 (X = BF 4, PF 6) and [Au(etpy) 2Cl 2][BF 4], were also obtained by reaction of Au(Rpy)Cl 3 with Rpy (1:1) and excess NaBF 4 or KPF 6. Thermal activation of Au(vinpy)Cl 3 in water gives the five-membered cycloaurated derivative [Au( k 2- C,N–CH 2CH(Cl)–C 5H 4N)Cl 2] formally resulting through a trans nucleophilic addition of a chloride onto the C C bond. No cyclometallated derivatives are obtained by reactions of Au(etpy)Cl 3. An X-ray crystal structure determination on the PPh 3 derivative [Au( k 2- C,N–CH 2CH(Cl)–C 5H 4N)(PPh 3)Cl][PF 6] was carried out.