Polymerized formic aldehyde

Polymerized Formic Aldehyde. See Vol 6, F164-L to F16S-L under Formaldehyde Polymers ... 

The steady state concentrations of HCN would have depended on the pH and temperature of the early oceans and the input rate of HCN from atmospheric synthesis. Assuming favorable production rates, Miyakawa et al (30) estimated steady state concentrations of HCN of 2 x 10 M at pH 8 and 0°C in the primitive oceans. At 100° C and pH 8 the steady state concentration was estimated as 7 x 10 M. HCN hydrolyzes to formamide which then hydrolyzes to formic acid and ammonia. It has been estimated that oligomerization and hydrolysis compete at approximately 10 M concentrations of HCN at pH 9 (31), although it has been shown that adenine is still produced from solutions as dilute as 10 M (32). If the concentration of HCN were as low as estimated, it is possible that HCN tetramer formation may have occurred on the primitive Earth in eutectic solutions of HCN-H2O, which may have existed in the polar regions of an Earth of the present average temperature. High yields of the HCN tetramer have been reported by cooling dilute cyanide solutions to temperatures between -10° C and -30° C for a few months (31). Production of adenine by HCN polymerization is accelerated by the presence of formaldehyde and other aldehydes, which could have also been available in the prebiotic environment (29). 

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