No protection? A unique, albeit fairly specialized, example of what promises to be a useful retrosynthetic consideration for those designing complex π-molecular systems, namely, using conformation as a protecting group to shield a given reactive site in lieu of protecting-group manipulation, is described (see scheme).
Conformational influences profoundly impact the performance of organic electronic materials and the reactivity of organic molecules. We recently found that the expected former consideration was uniquely accompanied by the latter. This report describes a surprisingly regioselective bromination that suggests the general use of conformation as a protecting group during complex molecule synthesis.