Iridium-Catalyzed C4-Alkylation of 2,6-Di-tert-butylphenol by Using Hydrogen-Borrowing Catalysis

An iridium-catalyzed hydrogen-borrowing process has been developed whereby 2,6-di- tert -butylphenol can be alkylated at the C4-position by using a range of primary alcohols (11 examples, 40–93% yield). Following this, a selection of the products obtained underwent retro-Friedel–Crafts reactions to provide para -substituted phenols, which could potentially undergo further synthetic manipulations.