Why chemists can’t quit palladium
Palladium catalysts are practically indispensable for making drugs, but the silvery-white metal is more expensive than gold, and molecules that contain palladium can be extremely toxic. Thrilling reports of palladium-free catalysts have repeatedly turned out to be sullied by tiny amounts of palladium contamination, which can cling to laboratory equipment and lurk in reagents. But hope springs eternal, with chemists going to extreme lengths to purge their labs of palladium in the quest for long-sought alternatives.