Decamethyldizincocene, a Stable Compound of Zn(I) with a Zn-Zn Bond

Unlike mercury, which has an extensive +1 oxidation state chemistry, zinc usually adopts the +2 oxidation state. Decamethyldizincocene, Zn₂(ɛ⁵-C₅Me₅)₂, an organometallic compound of Zn(I) formally derived from the dimetallic [Zn-Zn]²⁺ unit, has been isolated from the low-temperature (-10°C) reaction of Zn(C₅Me₅)₂ and Zn(C₂H₅)₂ in diethyl ether. X-ray studies show that it contains two eclipsed Zn(ɛ⁵-C₅Me₅) fragments with a Zn-Zn distance (+/- standard deviation) of 2.305(+/-3) angstroms, indicative of a metal-metal bonding interaction.