A study has been made of reactions of aromatic hydrocarbons (AHC) - benzene, toluene, o-xylene, cumene, naphthalene - with metal lanthanides (Nd, Pr, Gd, Eu, Tb) and d-transition metals (Ni, Ti, V) under conditions of mechanical activation at 20 degrees C. It was established that, under the conditions adopted, opening of the aromatic nucleus occurs with the formation of carbene active centres, leading to the production of polyconjugated polymers. Organometallic compounds and carbene complexes of metals are also formed. The possible mechanism of the reactions taking place is discussed.