Let's break down the question and each reaction: --- ## **What Type of Reaction?** All three are **Diels-Alder reactions**. A Diels-Alder reaction is a [4+2] cycloaddition between a diene (conjugated double bonds) and a dienophile (double or triple bond, often with electron-withdrawing groups). - **Endo and Exo Products:** - **Endo:** Substituents on the dienophile are oriented *under* the newly formed ring (towards the diene's π-system). Usually the major product due to secondary orbital interactions. - **Exo:** Substituents are *away* from the π-system (above the plane). --- ## **1. 1,3-Butadiene + Methyl Vinyl Ketone** **Structures:** - Diene: 1,3-Butadiene - Dienophile: Methyl vinyl ketone (CH₂=CH-COCH₃) **Product:** A cyclohexene ring forms, with a ketone at the 3-position and a methyl at the 4-position (numbering starts at the top of the diene). ### **Endo Product (Major)** - The carbonyl group is oriented under the ring. - Draw one enantiomer if chiral. ### **Exo Product (Minor)** - The carbonyl group is oriented away from the ring. --- ## **2. Benzene + Hexafluoro-2-butyne** **Note:** Benzene does **not** do Diels-Alder reactions; it is too stable (aromatic). But if you meant **furan** or **cyclopentadiene**, those would react. If this is benzene, **no reaction** occurs. --- ## **3. 2,5-Dimethylfuran + Maleic Anhydride** - Diene: 2,5-Dimethylfuran - Dienophile: Maleic anhydride ### **Endo Product (Major)** - The anhydride (two carbonyls) are oriented under the ring. - Show one enantiomer if chiral. ### **Exo Product (Minor)** - The anhydride is oriented away from the ring. --- ## **Summary Table** | Reaction | Major Product | Minor Product | Endo/Exo | Stereochemistry? | |----------|--------------|--------------|----------|------------------| | 1 | Endo | Exo | Yes | Show one enantiomer for each if chiral | | 2 | No reaction | - | - | - | | 3 | Endo | Exo | Yes | Show one enantiomer for each if chiral | --- ## **Drawing the Products** ### **How to Draw:** - Draw the cyclohexene ring for Diels-Alder. - Attach substituents at correct positions. - For endo: place EWG (like C=O, anhydride) *under* the ring. - For exo: place EWG *above* the ring. - If chiral, show wedge/dash for stereochemistry. --- ## **Example for 1st Reaction:** - **Endo (major):** - Cyclohexene ring - COCH₃ group under the ring (endo) - Methyl group - **Exo (minor):** - COCH₃ group above the ring (exo) - Methyl group --- If you want to see the actual structures drawn out, let me know! I can help sketch them or explain the step-by-step drawing.