Abstract: A caged phosphine product is provided which can act as a ligand to form a metal complex. The metal complex can be used as a catalyst.

Abstract: Organophosphines of the formula (R)aP(H)3−a( where R is C1-C20 alkyl, alkenyl, alkaryl or styryl and a is 1, 2, or 3) are produced by (i) reacting a tris(hydroxyorgano)phosphine (THP) with an organic halogen containing compound; (ii) reacting the product of (i) with a base; (iii) removing aldehydes from the product of (ii) and adding an organic phase, followed by distillation or phase-separation to obtain the desired product.

Abstract: A method for the preparation of alkene phosphonic acids and salts thereof, such as VDPA (vinylidene diphosphonic acid) is disclosed. The products can be produced in a stable, substantially pure form and in high yield. The method includes the azeotropic removal of water from salts of &agr;-hydroxy-alkane diphosphonic acid dimer or corresponding acids thereof, and the pyrolysis of the dehydrated reactant at a temperature of from 170° C. to 300° C. There may be included a step to convert anhydrides which have been formed during the pyrolysis. The method may include the use of heat transfer agents and/or bases, and may be carried out at elevated or reduced pressure.