β-Substituted organolithium compounds from chlorohydrins: application to the direct synthesis of bifunctionalized organic compounds

Abstract

The reaction of different chlorohydrins with n-butyl-lithium at –78 °C followed by metallation with lithium naphthalenide at the same temperature leads to very reactive organolithium compounds bearing an alkoxide function at the β-position with respect to the metal. The reaction of these intermediates with several electrophiles leads to mono- as well as bi-functionalized organic compounds. Thus, treatment of these dianions with deuterium oxide, oxygen, carbon dioxide, benzyl bromide, dimethyl disulphide, and carbonyl compounds, gave 2-deuterioalcohols, 1,2-diols, β-hydroxy-acids, 2-benzyl alcohols, 2-hydroxy-thioethers, and 1,3-diols respectively. The preparation of β-substituted organolithium derivatives can be alternatively carried out starting from α-chloroketones by the same procedure. When the lithium atom is linked to a secondary carbon atom the dianions are very unstable and decompose, even at –100 °C, by β-elimination yielding the corresponding olefins.