Synthesis of AZO intermediate

A synthesis for an azo intermediate, 5,5′-azobis(4-chloropyrimidine) is disclosed. 5,5′-azobis(4-chloropyrimidine) is a relatively stable azo compound in that decomposition does not occur until about 194° C. 5,5′-azobis(4-chloropyrimidine) is a product of oxidative dimerization of 5-amino-4-pyrimidine, which a water soluble compound. The azo intermediate is formed in an aqueous solution, but the azo intermediate is substantially insoluble in water; and as it forms it separates producing a reaction mixture that is a slurry. The azo intermediate is isolated by filtration. The azo intermediate is marginally soluble in acetone. The yield is at least 18%, and the oxidizing agent (bleach) is inexpensive, reaction conditions do not require extreme heat or cold, which taken together make the azo intermediate suitable for scaling up.