Equilibrium of α‐aminoacetonitrile formation from formaldehyde, hydrogen cyanide and ammonia in aqueous solution: Industrial and prebiotic significance

Abstract

Abstract The equilibrium constant, K , for the formation of α‐aminoacetonitrile from formaldehyde, ammonia and hydrogen cyanide was evaluated at 25°C. A first estimation of K was obtained from extrathermodynamic relationships of the type log K ′ vs ∑σ*. The final value was then obtained from a comparison of the experimental and calculated pH dependences of α‐hydroxy‐ and α‐aminoacetonitrile concentrations. From these results, it appears that, after equilibrium, the ratio between the concentrations of the two precursors glycine and hydroxyethanoic acid, is a linear function of the concentration of free ammonia, i.e. [CH 2 (OH)CN] [CH 2 (NH 2 )CN] = 21 [NH 3 ] at 25°C.