Epoxyphosphonic acids

Certain optical isomers of epoxyphosphonic acids also have antibacterial activity [274,275]. Phosphates and polyphosphates with bactericidal properties are described in Refs. 276 and 277. 

Christensen, B.G., and Cama, L.D., Antibacterial opticaUy-active epoxyphosphonic acid and its derivatives, Merck, German Patent Appl. DE 2002415, 1970 Chem. Abstr, 75, 77031s, 1971. 

Zbiral and co-workers reported on the reaction of mercaptotriazole with epoxyphosphonates 153 in acidic ethanol (88CB977). 

When diethyl 1-lithio-l-chloromethylphosphonate is treated with carbonyl compounds (aliphatic and aromatic aldehydes or ketones) in THF at low temperature, the intennediate chlorohydrin can eliminate upon warming to room temperature to give diethyl 1,2-epoxyphosphonates in good yields (51-90%) 2 or, in the case of aldehydes, can be treated at low temperature with LDA to give, after acidic work-up, diethyl 2-oxoalkylphosphonates in 65-92% yields (Scheme 3.63). 29. o... 

H) are readily separable, and each one converted to the corresponding 1,2-epoxyphosphonate (Scheme 4.13). Moreover, the use of these unsaturated intermediates allows the acid-catalyzed hydrolysis of the ester functions before epoxidation. 

Whereas oc-halohydrinphosphonates are converted into 1,2-epoxyphosphonates by treatment with strong bases, the corresponding P-halohydrins rearrange instantaneously in the presence of aqueous NaHCOj and slowly in water alone to give 1-formylethylphosphonic acid (Scheme 4.35). ... 

Different methods are known for the synthesis of dialkyl 1,2- epoxyalkylphosphonates. There are excellent reviews by Redmore [250], Yamamoto [251], and loga [252] describing the present methods for the synthesis of epoxyphosphonates. In this book, the following methods for the preparation of epoxyphosphonates based on diesters of H-phosphonic acid and their derivatives will be included (i) reaction of sodium dialkyl H-phosphonates with a-halo ketones, (ii) reaction of dialkyl halohydrinphosphonates with bases, (iii) the Darens reaction of dialkyl chloromethylphosphonates with carbonyl compounds, (iv) oxidation of 1,2-unsaturated phosphonates with a peroxide. 

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