Contribution to the chemistry of boron. 237. Bis(benzo-1,3,2-dioxaborolanyl)oxide and 2-(o-Hydroxyphenoxy)-benzo-1,3,2-dioxaborolane. Precursors for the synthesis of catecholborane (benzo-1,3,2-dioxaborolan)

Article abstract of DOI:10.1002/zaac.199762301142

The title compounds have been prepared from B(OH)₃ with catechol using different stoichiometries and were characterized by NMR spectroscopy and X-ray structure analysis. Bis(benzo-1,3,2-dioxoborolanyl)oxide, 3, has C₂ point group symmetry with a wide B-O-B bond angle (135.9°) in contrast to the new catecholester of boric acid, 2-(o-hydroxyphenoxy)-benzo-1,3,2-dioxaborolane, 4, which shows an almost planar molecular structure. These molecules form infinite chains in the solid state. 2-Hydroxy-1,3,2-dioxaborolane 6 crystallizes as a OH ? O bridged dimer. 3 proved to be a good starting material for the preparation of catecholborane (C₆H₄O₂)BH.