Annelation of Baylis–Hillman Derivatives: Synthesis of Highly Functionalised Tetrahydronaphthalenes

PTSA-promoted Robinson annelation of α-(3-oxobutyl)cyclohex-2-en-1-one derivatives in refluxing toluene, affords efficiently in a one pot process a variety of hydroxytetrahydronaphthyl carbonyl compounds in good yields. Further highly regioselective electrophilic bromination of these intermediates gave the corresponding bromide derivatives in 92–97% yield.