The copper catalysed reaction of unactivated aryl bromides with sodium methoxide has been investigated by studying a number of parameters (copper catalyst, cosolvent, concentration and relative ratio of the reactants, additives and aryl bromide substituents) which influence this reaction. 'Die ipso-substitution reaction was found to proceed via an intimate electron transfer mechanism involving a cuprate-like intermediate, Na[Cu(OMe)2]. A convenient synthesis of methyl aryl ethers from sryl bromides and concentrated sodium methoxide solutions in dimethyl formami de and methanol is presented. Also an attempt to extend this reaction to the use of chlorine derivatives was made.

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295ChemInform Abstract Tetrameric Cu(I) benzoate (Ia) and the o-halogen-substituted Cu(I) benzoates (Ib) and (Ic), the postulated intermediates in the Hurley reaction, react with the activated acetylenedicarboxylates (II) to yield the stable, tetranuclear complexes (III). Their structure is confirmed by X-ray structure analysis of the title complex (IIIb) (E: COOEt; space group P1, Z=2). The reaction of (Ib) and (Ic) with the less activated diphenylacetylene (IV) results in the formation of the dinuclear complexes (V) (no yields given). In methanol the reaction of (Ia) with dimethyl acetylenedicarboxylate shows a different reactivity pattern, leading to the trimerization of the alkyne. Variable-temp. 1H NMR spectroscopy and molecular weight determination of the complexes (III) (E: COOMe) indicate partial dissociation of the coordinated acetylene ligands in solutions.

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Abstract. The reaction of both the novel mixed trinuclear organo-organic copper