Science of Synthesis

Negishi, E.-i.; Takahashi, T., Science of Synthesis, (2003) 2, 681.

General Introduction

Zirconium was discovered by Berzelius in 1824.[‌1‌] It has an abundance of 0.022% in the lithosphere which is much less than titanium, but approximately 40 times greater than hafnium (0.00053%);[‌2‌] therefore, zirconium is about as abundant as carbon. More than a century after its discovery, Wilkinson reported bis(η5-cyclopentadienyl)dihalozirconium complexes [Zr(Cp)2X2, X = Cl, Br] as some of the earliest examples of organozirconium compounds.[‌3‌] Despite the fact that zirconium is one of the least-expensive transition metals, along with iron, copper, manganese, and titanium, the use of zirconium and organozirconium compounds in organic synthesis was virtually unknown until the 1970s, with the exception of zirconium salts as less frequently used Lewis acid catalysts in Friedel–Crafts reactions[‌4‌] and as generally inferior substitutes for titanium salts in the Ziegler–Natta polymerization;[‌5‌] thus, zirconium had largely remained a basic scientific curiosity. This situation has changed substantially over the past quarter of a century. Today, zirconium is one of the most widely used transition metals in organic synthesis, although it still lags behind copper and palladium in terms of versatility and frequency of use.

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References

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• 8.Meeeee-Meee, (8888) 88/8, 888.
• 8.Meeeee-Meee, (8888) 88/8, 888.