Vitamin B12 is an organometallic vitamin, known for its cobalt octahedral complex. This species has been recognized for various roles found throughout the human body, metabolism to cell division.1 Similar cobalt containing species are and is known to degrade in the presence of air or heat, however the Vitamin B12 functions as a coenzyme in biological conditions. In order to further examine the properties and functions of Vitamin B12, a model species like cobaloxmine are utilized. While the synthesis of cobalozmines must be carried out under inert conditions, they are much similar to produce than a Vitamin B12. Thus a species like Methyl(pyridine)cobaloxime is an ideal model compound for Vitamin B12.
Results
Methyl(pyridine)cobaloxime was prepared by a two-step synthesis. The first reaction involves a an oxidation of and redox with pyridine, yielding…show more content… 13C NMR of methyl(pyridine)cobaloxime in CDCl3.4
Discussion
The step-wise synthesis of Methyl(pyridine)cobaloxime was determined to be successful. The 1H NMR is identical to that found in literature despite some contamination of acetone at 2.19 ppm, as shown in Figure 3. Additionally, the 13C NMR is like that found in literate, despite the contamination at 207 and 31 ppm, as shown in Figure 4.2 This contamination was again due to acetone, which was present due to improper drying of the NMR tube used. Note that the Co-Me peak is absent to the Co spin of 7/2.
The oxidation state of the initial reactant, cobalt (II) nitrate hexahydrate, is +2. With oxidation, via the atmosphere, the cobalt species becomes +3. In second step of the reaction, NaBH4 functions as a reducing agent allowing the bromine group to be replaced with a pair of lone elections. The compound now has an oxidation state of +1. Then with the addition of MeI, cobalt is oxidized to a +3 state as the lone pair of electrons attack the methyl group; thus yielding the finial product.
