Essay on chemistry

3222 Words Mar 16th, 2014 13 Pages
Synthesis, Recrystallization of β-D-Glucose Pentaacetate from its Original D-Glucose and it comparison with literature though Melting point, TLC, IR, 1H and 13C NMR

Abstract:
The synthesis of the product: β-D-glucose pentaacetate is done though the acetylation using acetic anhydride with D-glucose with the help of sodium acetate. The recrystallization of the product is done though a polar solvent like water. The Result of this experiment has a percentage yield of 61% and analytical methods that are to detect the products are 1H NMR, 13 C NMR, COSY, FTIR (IR), Thin Layer Chromatography (TLC) and Melting point.
Introduction:
There are only several compounds and molecules that are essential to the human body. Such molecule
…show more content…
This pathway is less stable as the catalyst of the reaction: acetic anhydride carbonyl oxygen is basic and be stabilized by the ionization of sodium acetate that allows the attack on the anomeric acetoxy group rather than a rotation of the anomeric carbon. The adding of the acyl group gives one to a more resonance stabilized glucose pentaacetate 3.In the formation of β-d-glucose pentaacetate within this experiment, the goal is to yield as much of the selected theoretical product as much as possible and analyzed though 3 techniques: NMR, FTIR and TLC.
Figure 1. Schematic Diagram of the reaction scheme between the Reactants: D-glucose, sodium acetate and acetic anhydride to the product: β-D-glucose pentaacetate. (1) general anomerization of both d-glucose anomers, (2) mechanism of conversion from α to β-d-glucose. (3) acetylation from –d-glucose toβ-d-glucose pentaacetate
Results and Discussion
Figure 2. 1H and 13C NMR Labeling of β-D-Glucose Pentaacetate.
Table 1. Summary data showing 1H, COSY and 13C NMR data of β-D-glucose Pentaacetate Based on Figure 2
1H NMR (integration, splitting
1H (Experimental Chemical Shift PPM)
1H (Literature Chemical Shift PPM)9
1H (Experimental J-coupling Hz)
1H (Proton Coupling)
13C Experimental Chemical Shift PPM)
13C Literature Chemical Shift PPM)9
13C NMR number
H1 (I = 3, s)
2.018
2.018

20.71
20.56
C2
H2 (I = 6, s)
2.038
2.039

20.71
20.66
C2
H3

Related Documents