| abstract |
a) elementaren gelben Phosphor mit Alkylhalogeniden in Gegenwart von Alkali- oder Erdalkalihydroxidnzu einem Gemisch, welches als Hauptbestandteile die Alkali- und/oder Erdalkalisalzender Alkylphosphonigen, Phosphorigen und Hypophosphorigen Säure enthält, umsetzt b) aus dem nach a) erhaltenen Gemisch die Alkylphosphonige Säure entfernt, c) die Alkylphosphonige Säure verestert, d) den so erhaltenen Ester der Alkylphosphonigen Säure an eine Verbindung mit mindestensneiner C=C-Doppelbindung addiert. The present invention relates to a process for the preparation of phosphinic acid esters, which is characterized in that a) elemental yellow phosphorus with alkyl halides in the presence of alkali or alkaline earth metal hydroxide to form a mixture which contains the main constituents of the alkali metal and / or alkaline earth metal salts of alkylphosphonous, phosphorous and hypophosphorous acid b) the alkylphosphonous acid is removed from the mixture obtained according to a), c) esterifying the alkylphosphonous acid, d) the ester of alkylphosphonous acid thus obtained is added to a compound having at least one C = C double bond. n n n The invention also relates to the use of those produced by this processnPhosphinic acid esters, e.g. as a flame retardant and as a precursor for further syntheses. |