Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

Solutions of carbanions of living α-methylstyrene tetramer in tetrahydrofuran exhibit limited stability even at relatively low temperatures. The rate of decay of these active centers depends upon the type of counter-ion and it decreases in the sequence Li⁺ < Na⁺ < K⁺. It is dependent also upon temperature, concentration and some other unrevealed factors. In dark, with Na⁺ as a counter-ion at 263 K and ~ C^-Na⁺ concentration of 1.5 mmol/dm³, the initial period of a fast concentration decrease of active centers is followed by a very slow period of rate decay. At 296 K the decrease of their concentration is much faster and seems to obey a first reaction order. Rinsing the dry inner surface of glass apparatus by solutions of carbanions does not cause a decrease of their concentration. When a part of the glass apparatus is heated up to the softening point, a certain portion of carbanions is consumed.