Multimetallic Complexes and Functionalized Nanoparticles Based on Oxygen- and Nitrogen-Donor Combinations

Abstract

The versatile precursors [Ru(CH═CHC6H4Me-4)Cl(CO)(BTD)(PPh3)2] (BTD = 2,1,3-benzothiadiazole) and [Ru(C(C≡CPh)═CHPh)Cl(CO)(PPh3)2] were treated with isonicotinic acid, 4-cyanobenzoic acid, and 4-(4-pyridyl)benzoic acid under basic conditions to yield [Ru(vinyl)(O2CC5H4N)(CO)(PPh3)2], [Ru(vinyl)(O2CC6H4CN-4)(CO)(PPh3)2], and [Ru(vinyl){O2CC6H4(C5H4N)-4}(CO)(PPh3)2], respectively. The osmium analogue [Os(CH═CHC6H4Me-4)(O2CC5H4N)(CO)(PPh3)2] was also prepared. cis-[RuCl2(dppm)2] was used to prepare the cationic compounds [Ru(O2CC5H4N)(dppm)2](+) and [Ru{O2CC6H4(C5H4N)-4}(dppm)2](+). The treatment of 2 equiv of [Ru(C(C≡CPh)═CHPh)(O2CC5H4N)(CO)(PPh3)2] and [Ru(O2CC5H4N)(dppm)2](+) with AgOTf led to the trimetallic compounds [{Ru(C(C≡CPh)═CHPh)(CO)(PPh3)2(O2CC5H4N)}2Ag](+) and [{Ru(dppm)2(O2CC5H4N)}2Ag](3+). In a similar manner, the reaction of [Ru(O2CC5H4N)(dppm)2](+) with PdCl2 or K2PtCl4 yielded [{Ru(dppm)2(O2CC5H4N)}2MCl2](2+) (M = Pd, Pt). The reaction of [RuHCl(CO)(BTD)(PPh3)2] with HC≡CC6H4F-4 provided [Ru(CH═CHC6H4F-4)Cl(CO)(BTD)(PPh3)2], which was treated with isonicotinic acid and base to yield [Ru(CH═CHC6H4F-4)(O2CC5H4N)(CO)(PPh3)2]. The addition of [Au(C6F5)(tht)] (tht = tetrahydrothiophene) resulted in the formation of [Ru(CH═CHC6H4F-4){O2CC5H4N(AuC6F5)}(CO)(PPh3)2]. Similarly, [Ru(vinyl)(O2CC6H4CN-4)(CO)(PPh3)2] reacted with [Au(C6F5)(tht)] to provide [Ru(vinyl){O2CC6H4(CNAuC6F5)-4}(CO)(PPh3)2]. The reaction of 4-cyanobenzoic acid with [Au(C6F5)(tht)] yielded [Au(C6F5)(NCC6H4CO2H-4)]. This compound was used to prepare [Ru(CH═CHC6H4F-4){O2CC6H4(CNAuC6F5)-4}(CO)(PPh3)2], which was also formed on treatment of [Ru(CH═CHC6H4F-4)(O2CC6H4CN-4)(CO)(PPh3)2] with [Au(C6F5)(tht)]. The known compound [RhCl2(NC5H4CO2)(NC5H4CO2Na)3] and the new complex [RhCl2{NC5H4(C6H4CO2)-4}{NC5H4(C6H4CO2Na)-4}3] were prepared from RhCl3·3H2O and isonicotinic acid or 4-(4-pyridyl)benzoic acid, respectively. The former was treated with [Ru(CH═CHC6H4Me-4)Cl(CO)(BTD)(PPh3)2] to yield [RhCl2{NC5H4CO2(Ru(CH═CHC6H4Me-4)(CO)(PPh3)2}4]Cl. As an alternative route to pentametallic compounds, the Pd-coordinated porphyrin [(Pd-TPP)(p-CO2H)4] was treated with 4 equiv of [Ru(CH═CHR)Cl(CO)(BTD)(PPh3)2] in the presence of a base to yield [(Pd-TPP){p-CO2Ru(CH═CHR)(CO)(PPh3)2}4] (R = C6H4Me-4, CPh2OH). Where R = CPh2OH, treatment with HBF4 led to the formation of [(Pd-TPP){p-CO2Ru(═CHCH═CPh2)(CO)(PPh3)2}4](BF4)4. [(Pd-TPP){p-CO2Ru(dppm)2}4](PF6)4 was prepared from [(Pd-TPP)(p-CO2H)4] and cis-[RuCl2(dppm)2]. The reaction of AgNO3 with sodium borohydride in the presence of [Ru(O2CC5H4N)(dppm)2](+) or [RuR{O2CC6H4(C5H4N)-4}(dppm)2](+) provided silver nanoparticles Ag@[NC5H4CO2Ru(dppm)2](+) and Ag@[NC5H4{C6H4CO2Ru(dppm)2}-4](+).