Über α-substituierte Phosphonate. XXI. Zur Bildung von hydroxyarylsubstituierten Methan-bis-phosphonsäuretetraestern

α-Substituted Phosphonates. XXI. On the Formation of Hydroxyaryl-substituted Methane-bis-phosphonic Acid Tetraesters α-Amino-α-(4-hydroxy-3,5-di-tert.-butyl-phenyl)-methanephosphonic acid diethylester 1 can be converted by different methods to (4-hydroxy-3,5-di-tert.-butyl-phenyl)-bis-phosphonic acid tetraethylesters 2 . Course and intermediates of these smoothly proceeding reactions are investigated.