ABSTRACT The selective cleavage of the C–O bond of unactivated alkyl esters remains a major challenge to use them as C(sp 3 )‐electrophiles in cross‐coupling chemistry. Here, we report a systematic study on the dealkylation of alkyl formates using iodide salts, revealing the pivotal role of the Lewis acidic countercation (K + , Na + , Li + , Ca 2 + , Mg 2 + , and Al 3 + ) in accelerating C–O bond cleavage. Kinetic analyses demonstrate a seven‐order‐of‐magnitude rate enhancement when replacing LiI with AlI 3 . To highlight the synthetic potential of this finding, we further integrate this reactivity into a tandem catalytic system combining AlI 3 and a ruthenium catalyst, achieving efficient protodecarboxylation of alkyl formates to alkanes with up to 82 % yield.
Mandelaire et al. (2026) studied this question.