PULSE-RADIOLYSIS STUDY OF VITAMIN-K1 REDUCTION IN ETHANOLIC SOLUTION

A pulse radiolysis study of vitamin K-1 reduction was carried out in a rgon-saturated ethanolic solutions. The alpha-hydroxyethyl radicals (C H3CHOH)-H-. (R(.)) and the-solvated electrons, (e(solv)(-)) reduce vit amin K-1, leading to the semiquinone transient K1H.. This species, cha racterized by its absorption spectrum, decays by disproportionation an d leads to the formation of the hydroquinone K1H2. The rate constants of the monoelectronic exchanges involved in this reduction have been d etermined.