Regioselective Synthesis of Indanones

Abstract

The degree of hydrolysis of polyphosphoric acid (PPA) has a crucial effect on the regioselectivity of the PPA-mediated synthesis of indanones. It was found that the regioselectivity can be switched by employing PPA with either a high or low content of P₂O₅. This methodology was used for the regioselective synthesis of a range of electron-rich indanones, including a natural sesquiterpene.

Key words

indanones - polyphosphoric acid - electrophilic aromatic substitution - total synthesis - regioselectivity

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