The quest for stable carbenes

This article follows a thread through the history of the quest for stable carbenes. The story begins in 1835 with the attempts by Dumas to dehydrate methanol to produce methylene. It continues through modern times to a point where the accumulation of many false starts in stable carbene synthesis led to the conventional wisdom that carbenes are so highly reactive that they exist only as labile, short-lived molecules. The report of the isolation of the first stable crystalline carbene in 1991 began a renaissance in the chemistry of isolable carbenes. Much of the older chemistry is currently being revisited and reinterpreted with the aid of modern analytical techniques. Easily handled carbenes are opening many new opportunities in both exploratory chemistry and industrial applications.