Novel boron chelate complexes from the reaction of salicylaldehydes, tertiary amines, and diphenylborinic or phenylboronic acid. Crystal and molecular structures of two new types of chelated organoborate salts

{The one-pot reaction of equimolar amounts of salicylaldehyde, diphenylborinic acid anhydride, and a tertiary amine in the presence of an alkanol (R’OH) led to the addition of R’OH to the aldehyde group and the formation of an O,O-acetal moiety within the chelate anion with the charge balanced by an ammonium cation arising from the tertiary amine. Exchanging the diphenylborinic acid in the three-component reaction system for phenylboronic acid did not give the analogous adduct or chelate but one additional mole equivalent of phenylboronic acid (anhydride) was incorporated, leading to a polycyclic anion containing pyroboronate and acetal boronate functions with an associated ammonium cation. Crystals of 1-methylpiperidinium 4-ethoxy-2,2-dipheny1-1,3-dioxa-2-borata-1,2,3,4-tetrahydronaphthalenate , 6d, are monoclinic