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An expeditious synthetic methodology leading to substituted metahalophenols and their corresponding methyl ether derivatives through acidmediated fragmentation of suitably substituted dihalonorbornyl ketones has been devised. The reaction sequence consists of TBTHmediated TBTH is trinbutyltin hydride selective bridgehead halogen reduction of easily accessible Diels–Alder adducts derived from 1,2,3,4tetrahalo5,5dimethoxycyclopentadiene and βsubstituted vinyl acetates, with subsequent conversion into the requisite bicyclic ketones by a twostep hydrolysisoxidation approach. An extensive mechanistic investigation based on isotope labeling and cross experiments has been carried out and plausible mechanistic pathways based on these results have been proposed. The absence of halogen atoms at the bridgehead positions steers the reaction through a novel pathway involving the incorporation of proton or deuterium followed by elimination of HX or DX, so the described methodology also provides a reliable route to orthoparadideuteratedphenolic derivatives.