|This blog is not going to actually read Caffeine in your drink: natural or synthetic? by Lijun Zhang et al. (DOI). They imagine health issues with bad synthetic versus good natural caffeine and came up with a crazy over-the-top analytical tool ( high-temperature reversed-phase liquid chromatography / isotope ratio mass spectrometry if you need to know) to detect synthetic caffeine. According to Rajendrani Mukhopadhyay in C&EN it is against the law in some countries to replace natural with synthetic without mentioning it on the label. |
And what is so bad about this synthetic caffeine anyway. Compared to sourcing from coffee beans it is cheaper to manufacture, does not involve slave labour, is eco-friendly, does not require pesticides and quality control is easier.
But how is synthetic caffeine made? Wikipedia for some reason denies it exists. Thanks to a Ruhr University Bochum lab handout we have a clue. One method was invented by Wilhelm Traube already in 1900. Starting materials are dimethylurea and cyanoacetic acid. Reaction steps are acylation, then ring-closing with a Pinner reaction variation, then nitrosation (nitric acid), then reduction (sodium dithionite), then another ring-closing with formamide to theophylline and finally alkylation with iodomethane and a base. Modern industrial methods are adaptations. So remember next time at Starbucks: demand synthetic!