Nitrate as an Oxidant in the Reaction of Silver(I) Salts with Grignard Reagents

The reaction between various Grignard reagents and silver(I) salts in the presence of nitrogen-containing oxidants such as lithium nitrate, nitrogen dioxide, and methyl nitrate has been examined in tetrahydrofuran solutions. Coupling dimer is formed in high yields almost independently of the structure of the Grignard reagent. From the stoichiometry, it is concluded that these oxidants oxidize two equivalents of metallic silver formed in situ to silver(I) species under proper reaction conditions. Other transition metal halides are also oxidized by these oxidants in a similar manner. Soluble forms of reduced silver complexes formed in the reaction of silver(I) nitrate and Grignard reagent are also described.