2-AMINO-2-CARBOXYETHYLPHOSPHINIC ACID MONOHYDRATE

2-Amino-2-carboxyethylphosphinic acid exists as a zwitterion (2-ammoni o-2-carboxyethylphosphinate) with anionic phosphinic, cationic alkylam monium and neutral carboxyl groups. The P-C-C-C and P-C-C-N conformati ons are gauche and trans, respectively. In contrast to 2-amino-2-carbo xyethylphosphonic acid, intramolecular hydrogen bonding from ammonium to phosphinic moieties does not occur. Each phosphinic O atom accepts two intermolecular hydrogen bonds, as does the water molecule; every a mmonium, carboxyl and water H atom participates.