Abstract: A process for the manufacture of aromatic phosphorus derivatives of the formula:Ar.PO(OR).sub.2 (1)where R is an optionally substituted alkyl, alkenyl, aralkyl, cycloalkyl or aryl radical, and Ar is an aromatic radical linked to the phosphorus atom through a carbon atom of the aromatic radical which comprises contacting a phosphorous acid diester of the formula:HO.P(OR).sub.2 (2)with an aromatic halide of the formula Ar--X in the presence of copper or a copper compound, the symbols R and Ar having the meanings stated above and X representing a halogen atom.The aromatic radical preferably contains an atom or group activating the halogen atom. The process provides an improved method for manufacture of the phosphonic acid diesters.

Abstract: 5-(2-Hydroxyphenyl)tetrazoles having substituents containing at least 5 aliphatic or alicyclic carbon atoms are prepared from the corresponding o-hydroxybenzyl cyanides with alkali metal azides. These tetrazoles are useful as extracting agents in liquid-liquid extraction processes for metals, especially copper. When used in such processes in combination with o-hydroxyaryl oximes they improve the extraction kinetics of the oximes.