REACTION OF CARBON-MONOXIDE IN THE SUPERACID HSO3F-AU(SO3F)3 AND THE GOLD(I) BIS(CARBONYL) CATION [AU(CO)2]+ - ISOLATION AND CHARACTERIZATION OF GOLD(I) CARBONYL FLUOROSULFATE, AU(CO)SO3F

Solutions of gold tris(fluorosulfate), Au(SO3F)3, in fluorosulfuric acid, HSO3F, behave as superacids and will dissolve up to ~3.5 mol of CO/mol of Au(SO3F)3. During the CO uptake, Au(III) is reduced to Au(I), with Au+(solv) stabilized by CO to give the cation [(OC)Au(CO)]+(solv). The linear five-atom cation is characterized by its vibrational spectrum with CO stretching frequencies observed at 2251 (Raman) and 2211 (IR) cm−1. The cation is stable in solution, but solvent removal in vacuo leads to the formation of a new gold(I) monocarbonyl derivative, Au(CO)SO3F, in quantitative yield as a white solid. Au(CO)SO3F is thermally stable up to 190 °C. The CO stretch is found at 2198 and 2195 cm−1 in the Raman and IR spectra, respectively, well above the value of free CO. © 1990, American Chemical Society. All rights reserved.