tert-Carbocations, which were formed from hydrocarbons and alcohols, react with CO in the presence of catalytic amounts Of Cu(CO)n(+) to give, following a workup, with water tert-carboxylic acids upon workup with water catalyst. The salts of the cationic metal carbonyls such as [Pd(CO)(4)] [Sb2F11](2), [Pt(CO)(4)] [Sb2F11](2), [OsO2(CO)(6)] [Sb2F11](2) and [Hg(CO)(2)] [Sb2F11](2) promote the carbonylation of 3-hexanol and tert-C-7 carboxylic acids were obtained. Solid superacids such as Nafion, ZSM-5 to SO4/ZrO2 were used instead of H2SO4, in the catalytic sequence Ag+ was fixed on these solid superacids to form a silver carbonyl on the surface. The nu(CO) of the, silver carbonyl was observed at 2173 cm(-1) on Nation. The Ag+-supported solid superacids showed an activity higher than the original solid superacid during the carbonylation of alcohols. (C) 2002 Elsevier Science B.V. All rights reserved.