Carbonylation reactions with carbon monoxide (CO) provide efficient and attractive routes for the synthesis of
bulk and fine chemicals. However, the practice of using large excess of an inflammable, lethal and greenhouse CO gas is
always a concern in this chemistry. The development of CO surrogates have gained substantial interest and becoming a
green alternative to gaseous CO. Many of the recent studies have focused on the development of other benign and safe reagents to work as a CO source in carbonylation reactions, and the assortment of feasible CO surrogates for specific reaction
can be accomplished by the literature data. This review describes the recent developments in palladium catalyzed carbonyl
insertions without the direct use of gaseous CO.