Report about Synthesis of the 1,4-Dihydropyridine

ABSTRACT This is a scientific lab report prepared after an empirical observation. The main experiment is the synthesis of 1,4-Dihydropyridine. A simple dihydropyridine from a simple reactant (formaldehyde, ammonium acetate and 2,4-pentanedione ), is synthesized. The final part of this work deals with the determination of reasonable mechanisms for this synthesis. INTRODUCTION 1,4-Dihydropyridine is an equivalent of nicotinamide adenine dinucleotide (NADH) coenzymes. It exhibits a wide range of biological activities such as calcium channel blocking. Â  This explains their wide use today in pharmacology. Objective The aim of this experiment is to synthesize a sample of dihydropyridine and determine the mechanisms for this synthesis. Requirements Formaldehyde (1, 3.0 mmol), 2,4-pentanedione (2, 9.0 mmol), Ammonium acetate (3, 12 mmol), water, Source of heat. METHODOLOGY Procedure A mixture of formaldehyde (1, 3.0 mmol), 2,4-pentanedione (2, 9.0 mmol), and ammonium acetate (3, 12 mmol) in approximately 12 mL of water was heated at reflux for about 40 Minutes. Â  The mixture was then cooled, filtered and washed with 10 – 15 mL of water. Washing was done for the second time with approximately equal amount of water as in the first case. Results A pure solid product was obtained after washing. For confirmation on the purity of the solid substance, both IR and NMR spectrums, were obtained. A melting point of approximately 2200 C was also obtained. ANALYSIS A recrystallization from absolute ethanol is done if any findings point towards an impure product. In the analysis, the formaldehyde comes from 37% by weight solution. MW = 30 g/mol 2,4-pentanedione MW = 100 g/mol, Ammonium Acetate MW = 77 g/mol CONCLUSION The dihydropyridine is probably not (read not) very soluble in CDCl3 and therefore, use of DMSO/CDCl3 mixture for the NMR is employed.