Unsaturated Acids Ph SH,一C0OH H COOH IUPAC name: (E)-4-methy1-3-hexenoic acid trans-3-phenyl-2-propenoic acid new IUPAC name: (E)-4-methylhex-3-enoic acid (E)-3-phenylprop-2-enoic acid (cinnamic acid) Remove the final -e from alkene name,add the ending -oic acid. Stereochemistry is specified. Chapter 20 5Chapter 20 5 Unsaturated Acids ▪ Remove the final -e from alkene name, add the ending -oic acid. ▪ Stereochemistry is specified