Palladium-catalyzed mtion of a silcncy~cloptvpane with an a@ tri@te under carbon monari& pr~ssum (10-20 atm) in HMPA and that with carbon monoxide in chloroform provides new synthetic routes to 1,4-dicarbonyl compounds and I-keto pimelates, respectively. The reaction of a sikqycycloprvpane with a vinyl triflate, on the other hand, gives an acyloxycycloprvpane instead. Syntheses of cyclic and acyclic compounds often rely on the elaboration of polycarbonyl compounds, among which 1,3-and 1,4disposition of carbonyl functionality have proven particularly useful. While Claisen-type condensation has provided an important method for the preparation of 1,3dicarbonyl compounds, the classical synthesie of 1,klicarbonyl compounds and their higher homologues relying on disconnection A in Scheme I is not particularly versatile.1 Hence, disconnection B which involves either acyl anion2 or homoenolate anion3.4 have been explored as a useful alternative synthetic approach. Of the latter disconnection, metal-catalyzed coupling reactions of metal homoenolates (3-metallo carbonyl compounds)5 with acid chlorides are especially straightforward. The disconnection C shown in Scheme I representa an entirely new, third strategy that reliee on coupling of three-componenta, a metal homoenolate, carbonyl monoxide, and an aryl-cation eynthon.6 Practically, the reaction involves a palladium-catalyzed coupling of an aryl trifluoromethaneeulfonate kiflate1,7 carbon monoxide, and a silozycyclopropane 1 (eq 11, and is complementary to d§ion B in that the synthesis basically starts from phenol derivatives instead of benzoic acid or benzaldehyde derivatives required in the second approach.