science

In 2024, a research group led by UCLA chemist Neil Garg overturned Bredt's rule, a principle that had stood for more than a century. The rule states that molecules cannot form a carbon-carbon double bond at the "bridgehead" position (the ring junction of a bridged bicyclic molecule). Building on that breakthrough, Garg's team has now developed methods to create even stranger structures: cage-shaped molecules known as cubene and quadricyclene that contain highly unusual double bonds.