Diethylzinc chemistry alkylation

Zinc alkyls have been known to chemical science since the mid-nineteenth century and were among the first organometallic compounds produced and characterized. Sir Edward Frankland, an English chemist and pioneer in organometallic chemistry, synthesized diethylzinc (DEZ) from zinc metal and ethyl iodide (3). Remarkably, more than century and a half after its discovery, diethylzinc remains today an important industrial metal alkyl. Though quantities are substantially smaller than those of aluminum alkyls, diethylzinc has several niche applications in polyethylene processes. 

Edward Frankland (1825-1899) discovered the first transition metal alkyl complexes - diethylzinc ( mobile fluid") and ethyl-zinc iodide ( white mass of crystals ) - while he worked in Robert Bunsen s Marburg laboratory (1849). Frankland was later a professor of chemistry in London. Alkyl-metal bonding occurs in practically all catalytic processes involving hydrocarbons, e. g., hydroformylation (Section 2.1.1), hydrogenation of olefins (Section 2.2), hydrocarbon activation (Section 3.3.6), and C-H-activation (Chapter 4). 

In 1848, Edward Frankland attempted to prepare free ethyl radicals by the reaction of EtI with metallic zinc. Instead, he became the founder of organometallic chemistry by showing that the colorless liquid formed was diethylzinc, the first compound known to contain a metal-carbon bond. Victor Grignard s organomagnesium halides of 1900 made organometallic compounds indispensable in organic chemistry. Pope and Peachey s MesPtI (1909) was an early but isolated example of a d-block metal alkyl. 

Frankland discovered the first main-group alkyl, diethylzinc, in 1849 and other compounds such as dimethyhnercnry and tetraethyllead soon followed. These are very volatile and reactive liquids, though thermally stable at room temperature. At a time when little was known about lanthanide chemistry, it was natural to assume that lanthanide... 

Ozaki, H., Hirao, A., and Nakahama, S. (1995) Anionic polymerization of alkyl methacrylates in the presence of diethylzinc. Macromolecular Chemistry and Physics, 196,2099-2111. 

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