Life on Earth is built out of carbon. Chains of carbon atoms arranged in different ways, are the backbone of most of the molecules that form and regulate the living systems. These molecules, large and small, of course contain other elements. But the greatest challenge for chemists, when they try to replicate and even improve the ability of nature to build molecules derived Carbon (organic) has long been finding ways to create and break the chemical bonds between carbon atoms. Over the years, chemists synthetic organic chemistry have accumulated a vast array of these reactions used to build new molecular structures.
However, many organic reactions tend to form undesired side products, due to the conditions or highly activated molecules used. The Nobel Prize in Chemistry, 2010 reward for three chemicals that have developed new methods to build links between atoms carbon, very selective and relatively mild conditions. All three have developed reactions as they are called. Heck reactions, Negishi and Suzuki used palladium, silver metal, joining two molecules, using a single link between them. Over the past thirty years, these reactions have become basic tools and very valuable to any organic chemist.
Richard Heck developed its addition reaction based on palladium for the 60, running a series of scientific papers on this subject, before stipulating what would become the standard protocol for Heck reaction in 1972. In this standard, palladium acts as a catalyst, first "grabbing" one molecule, then another and then joining them and "dropping" the couple together, leaving himself unchanged by the process, something akin to a marriage bureau. In the Heck reaction, the first molecule always contains a link between a carbon atom and a halogen such as chlorine, and the second always contains a double bond between carbon atoms. Surprisingly, the reaction occurs at room temperature.
Ei-ichi Negishi and Akira Suzuki, who had worked casually with Herbert Brown, Nobel Nobel in Chemistry in 1979, expanded the range of application of the Heck reaction, mainly to develop new ways to change the second molecule involved. The molecule containing a carbon double bond is replaced by a molecule in the reaction of organozinc Negishi and organoborane molecule in the Suzuki reaction. Together, these three reactions, and variants that have been created from them, have dramatically improved both the potential and the efficiency of synthetic organic chemistry and contributed substantially to the construction of complex molecules that contribute to multiple areas of our lives daily, from agriculture to medicine.
Translation of original article written by Adam Smith, Editor in Chief, Nobelprice.org
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