The Chemistry of Isocyanides, their MultiComponent Reactions and their Libraries†

The first century of isocyanide chemistry, which was then still a rather empty part of Organic Chemistry, began in 1859. In 1958 isocyanides became generally available by dehydration the formylamines. One year later the four component reaction of isocyanides (U-4CR) was introduced. This one-pot reaction is accomplished just by mixing amines, carbonyl compounds, suitable acids and isocyanides. Most chemical reactions have their own ”scope and limitation”, whereas the U-4CR can convert almost all combinations of educts into their products. Until 1995 this chemistry was moderately used, but since then a new era of the U-4CR and its unions with further reactions have become increasingly popular, particularly as libraries. In industry this chemistry became one of its most often used methods of finding new desirable products. In contrast to most other areas of chemistry, isocyanide chemistry is not yet exhausted and still much progress can be expected there.