Why Is the Diels-Alder Reaction Called a Thermal [4+2] Cycloaddition

question 9

Multiple Choice

Why is the Diels-Alder reaction called a thermal [4+2] cycloaddition?

• A) Because the reaction is initiated by heat; the diene has four  electrons and the dienophile has two  electrons.
• B) Because the reaction is initiated by light; the diene has four  electrons and the dienophile has two  electrons.
• C) Because the reaction is initiated by heat; the dienophile has four  electrons and the diene has two  electrons.
• D) Because the reaction is initiated by light; the dienophile has four  electrons and the diene has two  electrons.

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Definitions:

Granular Cells

Cells that contain granules in their cytoplasm, which may store enzymes, hormones, or other substances involved in various biological processes.

Bicarbonate

A buffer that plays a vital role in maintaining the pH balance in the blood and other bodily fluids.

Pancreatic Juice

A liquid secreted by the pancreas that contains a variety of enzymes critical for the digestion of food in the small intestine.

Goblet Cells

Epithelial cells that secrete mucus to protect and lubricate many internal body surfaces.