In this reaction, it is necessary to form a terminal methylol group by the reaction of the aldehyde with the amine, and any aldehyde performing this function is operable. This reaction can be performed in one or two steps as described. Examples of aldehydes suited for this reaction include furfuraldehyde, benzaldehyde, acetaldehyde and formaldehyde. As mentioned before, then the resulting reaction product is reacted with HCN and subsequently
converted to the acid.