Patent ID: 9676799
Date: 2017-06-13
CPC Classifications: A01N,C07F,C12P

Claim:
1. A method for the synthesis of N-(phosphonomethyl)glycine or one of its derivatives selected from the group consisting of its salts, its phosphonate esters and its phosphonate ester salts, comprising the steps of: a) forming, in the presence of an acid catalyst, a reaction mixture comprising 2,5-diketopiperazine, formaldehyde and a compound comprising one or more P-O-P anhydride moieties, said moieties having one P atom at the oxidation state (+III) and the other P atom at the oxidation state (+III) or (+V), to form N,N′-bisphosphonomethyl-2,5-diketopiperazine, its mono- to tetra phosphonate esters, the dehydrated forms of N,N′-bisphosphonomethyl-2,5-diketopiperazine and the phosphonate esters of its dehydrated forms; and b) hydrolysing said N,N′-bisphosphonomethyl-2, 5-diketopiperazine, its dehydrated forms or their phosphonate esters to obtain N-(phosphonomethyl)glycine or one of its derivatives selected from the group consisting of its salts, its phosphonate esters and its phosphonate ester salts.