Abstract The relative ease of formation of five-, six-, seven-, and eight-membered cyclic benzeneboronates is discussed. Pentane-1, 3, 5-triol forms, by interaction with benzene- boronic anhydride, exclusively DL-4-(2-hydroxyethyl)-2-phenyl-1, 3, 2-dioxaborinane. It is suggested that, in this compound, the oxygen atom of the hydroxyl group is intramolecularly co-ordinated with the boron atom.
