A Novel Method for the Separation of Bis(α-hydroxyalkyl)phosphinic Acid Diastereoisomers via Formation of Novel Cyclic Phosphinic Acids

The reaction of aromatic and aliphatic aldehydes with
hypophosphorus acid under microwave irradiation was
examined. The reaction gave a mixture of a racemic pair of
bis(α-hydroxyalkyl)phosphinic acids and acetal derivatives
from the corresponding bis(α-hydroxyalkyl)phosphinic acids
of meso-stereochemistry in good yield. The difference in
solubility in organic solvents due to polarity allowed us to
readily separate these compounds. This method constitutes
an easy, rapid, and good-yielding preparation and separation
of bis(α-hydroxyalkyl) phosphinic acid diastereoisomers
from simple starting materials using microwave irradiation.