Here are the essential concepts you must grasp in order to answer the question correctly.
Enolate Ion Formation
Enolate ions are formed when a proton is removed from the alpha carbon of a carbonyl compound, such as an aldehyde or ketone, under basic conditions. This ion is resonance-stabilized and can exist in two forms, allowing for nucleophilic attack at either face of the carbonyl. This property is crucial for understanding how isomerization occurs, as it leads to the formation of different stereoisomers, including epimers.
Recommended video:
Epimerization
Epimerization is the process by which one epimer is converted into another through the reversible interconversion of stereoisomers at a specific chiral center. In the context of sugars, this occurs when the enolate ion formed from a sugar can be reprotonated at either face, resulting in a mixture of the original sugar and its epimer. This concept is essential for understanding how glucose can equilibrate with mannose under basic conditions.
Recommended video:
Base-Catalyzed Equilibration
Base-catalyzed equilibration refers to the process where a base facilitates the conversion of one isomer to another, often through the formation of reactive intermediates like enolate ions. In the case of glucose and mannose, the base removes a proton, allowing for the formation of an enolate that can then lead to the generation of both sugars. This mechanism highlights the role of basic conditions in promoting isomerization reactions in carbohydrates.
Recommended video: