Novel alkoxy derivatives of cobalt bis(1,2-dicarbollide)

•Approaches to alkoxy derivatives of cobalt bis(1,2-dicarbollide) presented.•One step protocol for [μ-8,8′-I-3,3′-Co(1,2-C2B9H10)2] worked up.•Series functionalized disubstituted cobalt bis(1,2-dicarbollides) synthesized.

Two approaches for the preparation of 8-iodo-8′alkoxy substituted cobalt bis(1,2-dicarbollides) were studied. The reactions of the 8-iodo-8′-hydroxy ([1]−) and 8,8′-dihydroxy ([2]−) derivatives of cobalt bis(dicarbollide) anion with alkylhalogenides were investigated. A new one step protocol for the preparation of cobalt bis(1,2-dicarbollide) iodonium bridged compound [μ-8,8′-I-3,3′-Co(1,2-C2B9H10)2] (3) was worked up. The reactions of compound 3 with various primary alcohols (methanol, ethanol, propargyl alcohol, 3-butyn-1-ol, ethylene glycol and 2-bromoethanol) led to the title ethers with good yields. Compound Cs[8-I-8′-OH-3,3′-Co(1,2-C2B9H10)2] (Cs[1]) was determined by single-crystal X-ray diffraction and it was found to be a coordination 2D polymer in a solid state.

Graphical abstractA single-step method of synthesis of the iodonium derivative of cobalt bis(dicarbollide) from unsubstituted cobalt bis(1,2-dicarbollide) and iodine in benzene in the presence of AlCl3 was developed. Reactions of [μ-8,8′-I-3,3′-Co(1,2-C2B9H10)2] with alcohols (methanol, ethanol, propargyl alcohol, 3-butyn-1-ol, ethylene glycol and 2-bromoethanol) led to the title ethers.Figure optionsDownload full-size imageDownload as PowerPoint slide