By polarimetric observations with regard to the effects of H3BO3, Na2B4O7 and KBO2 on various polyoxy compounds the following results and conclusion were obtained. Boric acid has a very feeble ability for complex formation with non-ionizable polyoxy compounds, such as mannit and glucose, while alkali borates show strong activity upon them. The order of the strengths is H3BO3<<Na2B4O7<KBO2. Complex is formed between borate ion and polyhydric alcohols. Its quantity increases with increasing BO2′. The effects of boric acid and alkali borates on ionizable polyoxy compounds, like tartaric acid and its salts, appear somewhat complicated. In this case complex formation is possible to a large extent between free boric acid and free tartaric acid (complex I). Complexes are also formed between alkali borate and alkali tartrates (complex II), but they (II) are different in structure from those formed in acidic medium (I). The complex I is formed by the action between BO2′ and alcoholic OH groups, but complex II between B(OH)3 molecule and COO′ ion. Calcium gluconate behaves toward boric acid and borates like alkali tartrates. H3BO3 combines with the COO′ group of the gluconate, while BO2′ reacts with its alcoholic OH groups. Thus it has been shown that the complex formation is in general based upon the reaction between molecule and ion, and not between neutral molecules nor between ions.

The infrared hydroxyl and carbonyl stretching absorption spectra of salicylic, mandelic, and α-hydroxyisobutyric acids have been measured in dilute carbon tetrachloride solutions. The spectral data indicate that the first two acids exist exclusively in an internally-bonded conformation, one where the phenolic and the alcoholic hydroxyl groups form a hydrogen bond with the carbonyl oxygen atom of the cis-carboxyl structure, while the last acid takes, apart from such a conformation, another internally-bonded conformation, one where the hydroxyl group of the trans-carboxyl structure interacts with the alcoholic oxygen atom.

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