Useful and Air-Stable Zinc(II) Chloride Equivalent

Dichloro(N,N,N',N'-tetramethylethane-1,2-diamine)zinc(II) (1) is a zinc complex coordinated by N,N,N',N'-tetramethylethylenediamine (TMEDA). Zinc(II) dichloride (ZnCl₂) is commonly used for the preparation of organozinc reagents. However, prepared organozinc species are partly decomposed due to hygroscopicity and the dissolution of ZnCl₂ to THF and ether solvents being exothermic. Therefore, commercially available THF or ether solutions of ZnCl₂ should be carefully handled after opening. On the other hand, 1 is air-stable and non-hygroscopic with easier handling and storage compared to that of ZnCl₂. 1 can be used for the preparation of organozinc species without hygroscopic decomposition. Now, 1 is applied to the synthesis of silole derivatives.