Adducts of trigonal-prismatic and octahedral metal clusters containing interstitial atoms (nitrogen or carbon) with [Au(PPh3)]+
Abstract
Spectroscopic evidence indicates that the anion [Rh6N(CO)15]– reacts with [Au(PPh3)Cl] to afford [Rh6N(CO)15{Au(PPh3)}], but there is no evidence that a similar reaction with either CF3CO2H or HBF4·Et2O leads to [Rh6(H)N(CO)15]. Addition of [Au(PPh3)Cl] to [Rh6C(CO)13]2– at –80 °C gives [Rh6C(CO)13{Au(PPh3)}]–, in which there is complete migration of the Au(PPh3) group and all the carbonyls around the Rh6 octahedron even at –80 °C. At higher temperatures, [Rh6C(CO)13{Au(PPh3)}]– loses CO and forms [Rh6C(CO)12{Au(PPh3)}]–, which has been characterised by a variety of multinuclear NMR measurements. Spectroscopic evidence is presented to suggest that a related 84-electron octahedral cluster [Rh6N(CO)12]– is formed, rather than the 86-electron cluster [Rh6N(CO)13]–, on heating [Rh6N(CO)15]–.