The solvent-free production and purification of compounds by mechanochemistry have gained importance in recent years. These processes yield fewer waste products and cost less than traditional solvent chemistry, making them ideal for experimentation regarding the synthesis of porphyrins. As a model reaction, benzaldehyde and pyrrole are ball-milled in the presence of an acid catalyst for a set time. This produces a cyclized precursor to a porphyrin, which is then oxidized to produce tetraphenylporphyrin (TPP). However, after oxidation, the reaction mixture also contains a number of undesirable byproducts. Our research focuses on the purification of TPP from this mechanochemical reaction mixture by entrainment sublimation with either air or nitrogen as a carrier gas. Since TPP sublimes at around 400 �C, this process will be carried out and optimized at the afore-mentioned temperature using a tube furnace with Pyrex processing tube. The purified yields from these experiments at varying heating rates, times, and gas flows will be reported.

Entrainment sublimation for purification of porphyrins synthesized by mechanochemistry

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.