chemistry
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 like D-glucose which is considers the second central substance in the maintenance and metabolite of human life after water. D-glucose is an important monosaccharide and has being subjected to many years of NMR analyses due to its anomeric properties of αand βusing deuterium1. Both anomers of D-glucose have a similar structure with a molecular formula of C6H12O6.Within normal conditions; D-glucose exists as a mixture of cyclic hemi-acetals (ring) and open-chain (acyclic) form within aqueous solution. The ring of D-glucose consists of 5 carbons and oxygen which each carbon is linked to a hydroxyl group with exception of the 5th carbon which is linked to a methyl-hydroxyl group. D-Glucose has 4 chiral centers when it is in ring form which the anomeric carbon appears at C1 which lead to the structure of α(axial, down) and β(equatorial, up) position 2. The ratio of this anomer exists within the aqueous state of α: β is 36:64 and interconvert with each other within a timescale. This process is called Mutarotaion2. Both anomers can be linked to other sugars but differently as the α-glucose resemble more in to starch while β-glucose resembles cellulose and is indigestible to humans. Within this experiment, the uses of acid catalyst such as
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 like D-glucose which is considers the second central substance in the maintenance and metabolite of human life after water. D-glucose is an important monosaccharide and has being subjected to many years of NMR analyses due to its anomeric properties of αand βusing deuterium1. Both anomers of D-glucose have a similar structure with a molecular formula of C6H12O6.Within normal conditions; D-glucose exists as a mixture of cyclic hemi-acetals (ring) and open-chain (acyclic) form within aqueous solution. The ring of D-glucose consists of 5 carbons and oxygen which each carbon is linked to a hydroxyl group with exception of the 5th carbon which is linked to a methyl-hydroxyl group. D-Glucose has 4 chiral centers when it is in ring form which the anomeric carbon appears at C1 which lead to the structure of α(axial, down) and β(equatorial, up) position 2. The ratio of this anomer exists within the aqueous state of α: β is 36:64 and interconvert with each other within a timescale. This process is called Mutarotaion2. Both anomers can be linked to other sugars but differently as the α-glucose resemble more in to starch while β-glucose resembles cellulose and is indigestible to humans. Within this experiment, the uses of acid catalyst such as
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