The use of microfluidic hardware in the synthesis of oligohexamethylene guanidine derivatives

Objectives. To develop a method for the microfluidic synthesis of oligohexamethylene guanidine salts in a flow-type reactor and to evaluate its effectiveness in relation to the synthesis in a traditional capacitive reactor and compare the purities of products obtained by these methods.
Methods. The synthesis of oligohexamethylene guanidine bihydrocarbonate (OHMG-BHC) was done using microfluidic hardware and the classical approach in volume. The purity and structure of the resulting product were confirmed by 13C NMR spectroscopy and high-performance liquid chromatography (HPLC).
Results. The 13C NMR spectrum of OHMG-BHC in classical bulk synthesis demonstrates that the product is unbranched and contains additionally unidentifiable impurities, in contrast to the sample obtained by the microfluidic method. Furthermore, the HPLC analysis showed that the OHMG-BHC sample synthesized using microfluidic technology has a 1.5-fold lower content than the initial monomers.
Conclusions. The advantage of synthesizing OHMG-BHC in a flow-type reactor compared to the traditional method of synthesis in volume is demonstrated since a product with a higher degree of purity is obtained.

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