| OBSERVATION'S |
Many people credit the ruthenium catalysts of Grubbs with putting olefin metathesis in the forefront of organic synthesis. The ruthenium compounds have high preference for carbon-carbon double bonds and are indifferent to alcohols, amides, aldehydes, and carboxylic acids. More important, their use does not require stringent conditions, Grubbs says. They can be used by organic chemists applying standard techniques. Vacuum lines and dry boxes, which are needed when working with Schrock's molybdenum catalysts, are not necessary.
The first of Grubbs's ruthenium catalysts was prepared in 1992. It had good functional group tolerance but limited activity. Further refinements led in 1996 to the catalyst (PCy3)2Cl2Ru5CHC6H5 (Cy=cyclohexyl), which is now widely known as the Grubbs catalyst
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