Synthesis of lithium omega-(m- and p-lithiophenoxy)alkoxides modified withmagnesium 2-ethoxyethoxide. Crystal structures of bis[4-(2-hydroxyethoxy)phenyl]mercury and bis[4-(3-hydroxypropoxy)phenyl]mercury

m- and p-Chlorinated omega-phenoxyalcohols 1, were transformed into the cor responding lithium omega-(m- and p-lithiophenoxy)alkoxides 4, respectively, by successive deprotonation with n-butyllithium and subsequent chlorine-li thium exchange by lithium naphthalene radical anion in THF-methylcyclohexan e. Lithium 2-(4-lithiophenoxy)ethoxide (4a') was also prepared by bromine-l ithium exchange of 2-(4-bromophenoxy)ethanol (2a') with two equivalents of n-butyllithium. The organolithiums were modified with magnesium 2-ethoxyeth oxide in order to avoid ortho-metallation of the above-mentioned substitute d arenes. Subsequent reaction of these intermediates with the electrophiles carbon dioxide, benzophenone, benzonitrile and 0.5 equivalents of mercuric chloride yielded the expected m- and p-substituted (omega-hydroxyalkoxy)be nzenes in yields ranging from 50 to 75%. The crystal structures of the orga nomercurials 8a' and 8b' have been determined and revealed the HE atom to o ccupy a crystallographic center of symmetry in a linear C-Hg-C arrangement. (C) 1999 Elsevier Science S.A. All rights reserved.