Mild hydrolytic cleavage of α-ferrocenylalkyl-O-methyl ethers

The conversion of α-ferrocenylalkyl-O-methyl ethers into the corresponding alcohols was successfully achieved by solvolysis in water/acetone mixtures. The content of water in the solvent markedly influenced the reaction rates. The reactivity of structurally different classes of ferrocenyl ethers was evaluated and in most cases high yields of ferrocenyl alcohols or diols were obtained in a few hours without any additive. Deprotection of less reactive substrates was accelerated in the presence of montmorillonite. The method is simple, environmentally benign and valuable in providing easy access to a variety of ferrocenyl derivatives through the use of the -O-methyl ether protective group.

Solvolysis of O-methyl ethers of structurally different α-ferrocenyl alcohols has been carried out in acetone/water mixtures, in some cases with montmorillonite K-10 as acid catalyst, to afford the corresponding alcohols or diols in high yields. The content of water in the solvent markedly influenced the reaction rates.