Phosphonic acid compounds and the preparation and use thereof.

摘要

The cyclic ether bis-phosphonic acids diphosphonotetrahydrofuran, diphosphonotetrahydropyran, and diphosphonooxepane and their salts and esters are disclosed, as is their use in water treatment. Also disclosed is the preparation of the cyclic ether bis-phosphonic acid compounds by reacting a corresponding dialkoxy cyclic ether with certain dialkyl phosphites, reacting the intermediate formed therefrom with certain halotrimethyl silanes, organic acid halides or inorganic acid halides, and reacting the intermediate formed therefrom with certain trialkyl phosphites to form a bis-phosphonic acid compound which may be hydrolized to form the cyclic ether bis-phosphonic acid. Certain of the first intermediates are considered stable reagents which may be used for preparing flame retardants, chelating agents and corrosion inhibitors.