Macrocyclic Synthesis (Heme Analog)
I.Purpose of Experiment and Introduction
The purpose of this lab experiment is to prepare meso-tetraphenylporphin (TPP) and its copper, cobalt or zinc complex by condensing benzaldehyde with pyrrole in boiling propanoic acid.
II.Introduction and Background
There are two types of proteins that function as oxygen carriers: myoglobin (stores the oxygen) and hemoglobin (present in red blood cells and is responsible for oxygen transport). The heme unit is a planar macrocyclic organic molecule that is made of four linked pyrrole rings surrounding an iron atom. These types of macrocyclic, nitrogen-containing molecules are known as porphyrins and are able to complex metal ions. The simplest unsubstituted porphyrin contains 18 delocalized electrons, planar, aromatic known as porphyrin. All these porphyrins have high molar absorptivity, which can be detected by UV spectroscopy in very low concentrations.
III.Chemicals and Equipment
Round Bottom flask
Graduated Plastic Syringes
Placed 18.6 mL of propanoic acid in a 100ml round-bottomed flask with boiling chips, fit a reflux condenser and brought the acid to reflux. Simultaneously, added .33mL of pyrrole and .47 mL of benzaldehyde through the condenser by using plastic syringes and allowed the mixture to heat under the reflux for 30 minutes. Cooled the mixture to room temperature and collected the product by suction filtration. Rinsed the product using methanol and allowed product to dry for several minutes. Step 2:
Placed 4.7 mL of DMF in a 25 Erlenmeyer flask with a few boiling stones. Heated the flask on a hot plate until it boiled gently. From the first step, added 0.048g of TPP to the hot DMF and allowed...