Patent ID: 8293938

Claim:
A process for the production of an alkylphosphonous acid, alkylphosphonous salt or alkylphosphonous ester, comprising the step of reacting a source of phosphinic acid with one or more olefins in the presence of a catalyst or a catalyst system, and where the source of phosphinic acid is phosphinic acid, a salt of phosphinic acid, an ester of phosphinic acid, or a mixture of these, wherein the catalyst is a transition metal, transition metal compound or wherein the catalyst system is a transition metal, a transition metal compound, and at least one ligand, wherein the one or more olefins are ethylene, 1-propylene, 1-butene, 1,3-butadiene, 3 methyl-but-1-ene or a mixture thereof, wherein the transition metal and transition metal compound are rhodium, nickel, palladium, platinum or a combination thereof and wherein the partial pressure of the olefin during the reaction is from 0.1 to 10 bar.