Efficient synthesis of protected l-phosphonophenylalanine (Ppa) derivatives suitable for solid phase peptide synthesis

l-Phosphonophenylalanine (Ppa) derivatives were synthesized from l-4-iodophenylalanine and suitably protected phosphites using Michaelis-Arbuzov reaction conditions in the presence of Pd(0) and triethylamine at 70 ± 2 °C.