LITHIUM-POTASSIUM EXCHANGE IN ALKYLLITHIUM/POTASSIUM t-PENTOXIDE SYSTEMS XIV. INTERACTIONS OF ALKOXIDES

Article abstract of DOI:10.1016/0022-328X(87)80117-1

Benzylpotassium containing only traces of lithium compounds is formed in the reaction of alkyllithium, potassium alkoxide and toluene over broad ranges of molar ratios of the reaction components and reaction times.This confirms that metal-metal exchange is occurring under the conditions used.The potassium alkoxide is used in stoichiometric amount for the metallation of toluene and is not only a catalyst.Use of a larger excess of potassium alkoxide leads to formation of its adduct with benzylpotassium.Various mechanisms for the above reaction are considered and formation of lithium alkoxide is assumed to help drive the equilibria towards the observed products.