Synthesis of dimethylamine from hydrocarbon
Synthesis of cyanoguanidine from hydrocarbon
Next, the calcium carbide is converted to calcium cyanamide (CaCN2) by reaction with N2 gas at 1100 °C (the Frank-Caro process) . Finally, calcium cyanamide is transformed to the desired cyanoguanidine over a two step process . First, the calcium cyanamide is reacted with water in the presence of carbon dioxide:
Production of reagents: ammonia and calcium oxide
In addition, our synthesis of cyanoguanidine required calcium oxide (CaO). This is cheaply accessible through thermal decomposition of calcium carbonate:
In summary, a useful and structurally interesting drug, metformin, can be prepared using remarkably simple starting materials: hydrocarbon, water, limestone, and nitrogen.