Phenyl-, Benzyl-, and Unsymmetrical Hydroxy-Methylenebisphosphonates as Dronic Acid Ester Analogues from alpha-Oxophosphonates by Microwave-Assisted Syntheses

作者：Keglevich Gyoergy^*; Gruen Alajos; Molnar Istvan Gabor; Greiner Istvan

来源：Heteroatom Chemistry, 2011, 22(5): 640-648.

DOI：10.1002/hc.20727

The microwave (MW)-assisted addition of dialkyl phosphites to alpha-oxophosphonates was investigated and optimized under solventless conditions to provide the phenyl- and benzyl-hydroxy-methylenebisphosphonates efficiently by suppressing the rearrangement side reaction. Methyl-hydroxy-methylenebisphosphonates with mixed ester functionalities and an analogous diesterdiacid were also synthesized. It was found that the alpha-oxophosphonates may also be converted to hydroxy-methylenebisphosphonates and/or rearranged products without using dialkyl phosphite as the reagent and with the careful exclusion of water, simply on standing at room temperature, on thermal treatment, or on MW irradiation. These novel reactions taking place via the controlled decomposition of the precursor and resulting in the intermediate formation of dialkyl phosphite were also studied in detail.

• 出版日期2011