ELECTRON-TRANSFER REACTIONS IN ORGANIC-CHEMISTRY .23. PRODUCTS, KINETICS AND INVERTED SPIN-TRAPPING IN THE REACTION BETWEEN CARBOXYLATES AND HEXACHLOROOSMATE(V) ION

The reaction between carboxylates and hexachloroosmate(V) has been investigated. For carboxylates, RCOO(-), corresponding to radicals R(.) which are difficult to oxidize (with E(i) larger than similar to 9 eV) the reaction gave one-electron oxidation products, as typified by the formation of C-to-N coupling products in good yield from tert-butylcyanoacetate ion. The kinetics of the reaction between the hydrogendiacetate ion and OsCl6- in acetonitrile was studied in more detail and found to conform to a kinetic model involving a second-order electron-transfer step between acetate ion (existing in equilibrium with acetic acid and hydrogendiacetate ion) and OsCl6-.