Separation of a mixture of paraconic acids from Cetraria islandica (L.) Ach. employing a fluorous tag—catch and release strategy

A light-fluorous catch and release approach application has been designed to the separation of a mixture of three paraconic acids extracted from the Island moss (Cetraria islandica (L.) Ach.). The (+)-protolichesterinic acid was caught and released via a Michael/retro-Michael addition sequence with a fluorous thiol, while the resulting two other compounds were classically separated, allowing the isolation of (+)-roccellaric acid for the first time in this lichen.