Diethylzinc

Introduction

Diethylzinc (ZnEt₂, bp = 118 °C at 760 mmHg) is an inexpensive and commonly used diorganozinc reagent.[1] Due to its high pyrophoric nature, diethylzinc is often commercialized as a solution in organic solvent (hexane, toluene, or heptane).

ZnEt₂ was first synthesized by Frankland in 1849 by heating ethyl iodide with zinc metal.[2] To facilitate purification, other methods have been developed, such as the transmetalation of a zinc halide with an organometallic reagent.[3] The use of this reagent has gained attention thanks to its application in asymmetric synthesis.

Diethylzinc is a versatile nucleophile that is suited for metal catalysis due to the highly covalent character of the carbon–zinc bond and the low Lewis acidity of zinc(II). Moreover, the empty low-lying p-orbitals allow facile transmetalation reactions.

• References

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