β-Mercapto-p-chlorohydrocinnamic acid, β-mercapto-p-methoxyhydrocinnamic acid, β-mercapto-β-(1-naphthyl) propionic acid, and β-mercapto-β-(2-furyl) propionic acid and their alkyl esters were prepared. These β-mercapto-acid esters formed stable chelates with copper and nickel. The ratio of ligand to the metal was 1 : 1 in copper chelates and 2 : 1 in nickel chelates. The reaction with nickel was particularly sensitive.
