My fist ever "had to make chemical" was 2-carboxyethyl-5-bromo-indole and we had 4-bromophenylhydrazine as a starting material. It looked like an easy
experiment, a simple Fischer indole synetesis with some ethyl pyruvate. The first part went awesome, the hydrazone formed, crytsallized and I've got
an almost white crystalline solid, but the ring forming caused some problem. It was described in a patent to use polyphosphoric acid and heat it to
100Celsius for a while. I've got a brown-black insoluble mass, similar to potting soil. NMR spectra was strange, because all aromatics have gone. The
other strange was that in the patent they described the pure material as a brown solid... -according to my data it contained no indole, so they simply
lied.
After a lot attept I had made the goal compound as a white-yellowish beautiful crystalline compound, but it was made by my method and not after the
journals.
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