“To a 250 ml RBF there was added 1.0g of guanine(6.6 mmol) 16 mls of water and 4mls of a 50wt% HCl solution. The guanine at first did not go into
solution (the free base is known to be insoluble in water) the addition of the HCl seemed to help (formation of the more soluble salt?) then an ice
bath was added and the temp of the rxn flask was droped to -5c. Sodium nitrite 0.46g (6.7mmol) was added to 4mls of chilled water. This chilled
solution was added over the course of 1 min. after addition the once white solution had taken on a yellow tint (perhaps N02 side product?). This
solution was held for ten mins. KI 1.0g (6.7mmol) was then added in small portions. Right away the solution thickened and changed to a black color
with evolving gas (n2?). Once all the KI was added rxn was stired for 10 mins. Sodium thiosulfate 10wt% was added to the black solution. Addition
immediately cleared up the black solution. The once sludgy appearance had all but dissipated. A yellow precipitate was noted. Solution was filtered to
remove the solids. Solids were washed with thiosulfate but yellow color did not wash out. The yield was 80%. Product solubility seemed to be the same
as guanine. Leading me to believe that the synthesis failed.
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