Sentence Examples

  • Chromium oxychloride reacts violently on phenol, producing hydroquinone ether, O(C 6 H 4 OH)2; chromic acid gives phenoquinone, and potassium permanganate gives paradiphenol, oxalic acid, and some salicylic acid (R.
  • All four mono-hydroxyxanthones are known, and are prepared by heating salicylic acid with either resorcin, pyrocatechin or hydroquinone; they are yellow crystalline solids, which act as dyestuffs.
  • 7-dihydroxyxanthone, known as euxanthone, is prepared by heating euxanthic acid with hydrochloric acid or by heating hydroquinone carboxylic acid with 3-resorcylic acid and acetic anhydride (S.
  • 7-trihydroxyxanthone, is found in the form of its methyl ether (gentisin) in gentian root; it is obtained synthetically by condensing phloroglucin with hydroquinone carboxylic acid.
  • It crystallizes in tables which melt at 140° C. and boil at 267° C. When heated with 10% hydrochloric acid to 180 C. it yields hydroquinone (J.