Mixed metal acylium clusters: A chemical and spectroscopic study

The generation of mixed metal acylium cations [MCo2(CO)6CCO]+, M = (C5H5Mo(CO)2, (C5Me5)Mo(CO)2 and (C5H5, from the parent esters via treatment with HPF6 in propionic anhydride is described. These cations and also the related [(C5H5)2Co3(CO)4CCO]+ cluster react with alcohols to give esters and with indole or pyrrole to give Friedel-Crafts type products. 1H NMR, IR and FAB mass spectroscopic data are reported.