In this green chemistry experiment of 5,10,15,20-tetraphenylporphyrin was synthesized from benzaldehyde and pyrrole. using microwave irradiation to heat the reactants., The liquid reactants are absorbed on a solid support, silica gel, which acts as a Lewis acid catalyst to facilitate the reaction. The reaction forms a porphyrinogen, which is then oxidized to the porphyrin product by atmospheric oxygen. Column chromatography is performed for the isolation and purification of tetraphenlyporphin, and the thin layer chromatography for analysis.It was concluded that the renention factor(Rf) of the 5,10,15,20- Tetraphenylporphyrin with a percent yield of 61%
In this experiment 5,10,15,20, tetraphenylporphyrin was prepared, from four molecules each of pyrrole and benzaldehyde. A method of porphyrin synthesis that is solventless is carried out on a solid support. The two reagents, pyrrole and benzaldehyde, react on the support under irradiation in a conventional microwave oven. The product is absorbed on a solid support with a small amount of silica gel wich is used as an Lewis acid catalyst to speed up the reaction. Oxidation of the porphyrinogen during the reaction yields the porphyrin .Usually porphyrins are purified by column chromatography often traditional halogenated solvents. However in this green chemistry experiment, a safer chromatography solvent mixture (hexanes and ethyl acetate) is used to help with the avoidance of solvent usage, the use of solid supported reactions and the use of alternative energy sources. Materials & Methods
* 0.43ml of Benzaldehyde 0.30ml of pyrrole
* 0.63g of Silica Gel 15ml of Ethyl Acetate * 25 mL Erlenmelyer flask Glass rod
* Microwave oven Pyrex watch glass
* Beaker Cuvette
* UV-VIS spectroscopy
* 0.43 mL of benzaldehyde...