On the mechanism of reduction of maleate and fumarate by Ni ^I(1,4,8,11-tetraazacyclotetradecane)⁺ in aqueous solutions

Ni^I(1,4,8,11-tetraazacyclotetradecane)⁺, Ni(I)L ⁺, was produced in neutral aqueous solutions by radiolytic techniques. The mechanism and kinetics of the reaction of Ni(I)L⁺ with maleate and fumarate were studied applying pulse-radiolysis and analysis of the final products. Surprisingly the mechanisms of reduction of maleate and fumarate differ considerably. Based on the results it was also shown that Ni(II)L²⁺ is an electrocatalyst for the reduction of alkenes in aqueous solutions.