Stubbornly Committed to PBG

So, I finally had my Photobase Generator, but lots of questions.

First, why did it seem to release acid upon irradiation? Upon reviewing the paper in which this molecule was synthesized, I discovered that they had published no actual pH data, only that the product had decomposed upon irradiation into two products, one of which was cyclohexylamine, the basic compound. Because cyclohexylamine was released, it had been classified as a photobase generating solution, which made sense. However, 6-nitrocoumarin was another product, and I couldn’t find any record of it’s acidic properties. My assumption was that perhaps the nitrocoumarin was actually more acidic than the cylclohexylamine was basic. Perhaps that would account for the drop of pH. However, quick tests proved that the nitrocoumarin was relatively basic, so that couldn’t be the solution.

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