The central and conserved role of peptides in extant biology suggests that they played animportant role during the origins of life. Strecker amino acid synthesis appears to be prebiotic,but the high pKaHof ammonia (pKaH=9.2) necessitates high pH reaction conditions torealise efficient synthesis, which places difficult environmental constraints on prebiotic aminoacid synthesis. Here we demonstrate that diamidophosphate reacts efficiently with simplealdehydes and hydrogen cyanide in water at neutral pH to affordN-phosphoro-aminonitriles.N-Phosphoro-aminonitrile synthesis is highly selective for aldehydes; ketones give poorconversion.N-Phosphoro-aminonitriles react with hydrogen sulfide at neutral pH to furnishaminothioamides. The high yield (73%–Quant.) of N-phosphoro-aminonitriles at neutral pH, and their selective transformations, may provide new insights into prebiotic amino acid synthesis and activation