Draw the structure of a compound with molecular C 8 H 14 that reacts with one equivalent of H 2 over Pd/C to form a meso compound

Welcome back, everyone provide the compound with the molecular formula C seven H 12 that will react with only one equivalent of hydrogen gas in the presence of palladium over carbon catalyst to produce a meso compound. Now, first of all, we're going to identify the hydrogen deficiency index because we're given the molecular formula according to the formula. We're going to use one half multiplied by two, multiplied by the number of carbon atoms plus two minus the hydrogen atoms in our structure. We don't need to include nitrogens or halogens, right? Because we're given a hydrocarbon. So we take one half multiplied by two, multiplied by seven plus two minus 12. What do we get? Well, essentially we get four divided by two, which is two. But the problem states that the compound reacts with only one equivalent of hydrogen. What does that mean? Well, essentially we will have one rank and one double bond because a hydrogen deficiency index of two can mean two double bonds or a triple bond, right? And that means we could actually have two equivalents of hydrogen reacting with the compound. So apparently there must be one rank. Now, if hydrogenation produces a measle compound. That means we need number one, at least two chiral centers. So that'll be at least right. And number two, we need to have a plane of symmetry, an internal plane of symmetry, we also know that the hydrogenation produces a sin addition, right. So let's think about our possibilities. We want to get a ring to begin with. If we draw a six member ring, we only have one carbon remaining, right? We cannot have any chiral carbon atoms within the ring itself because we don't have any hetero atoms. So we can exclude a possibility of a six membered ring. If we draw a six membered ring, we will essentially get an additional carbon that will be carbon number seven, then we want to place a double bond and apparently we cannot get any chiral centers other than one carbon atom, right? Only one carbon atom can be chiral that has potentially a methyl group. So we can decrease the ring size to a five member ring. Let's go ahead and do that. Let's draw a five member ring. OK. And now we want to make sure that the structure is symmetrical. So let's suppose that we draw a diagonal plane of symmetry passing through the five membered ring. And let's simply add two methyl groups to the neighboring carbon atoms. Now, in order to get that plane of symmetry, we also want to include a double bond between those two carbon atoms. So this is a possibility for us. Now, let's think if this structure meets the criteria specifically, when we perform the hydrogenation, this compound, we'll get two hydrogen atoms added to the SP two hybridized carbon atoms. So if we add the hydrogen in the presence of podium over carbon, we're indeed going to get a meso structure. Let's understand why. Well, essentially hydrogenation follows the sin addition principle. So we're going to add two hydrogen atoms on the same face of the five membered ring, meaning we can essentially add two hydrogen atoms pointing down right, warm up. And now what we noticed is that we have obtained two chiral centers. If we flip the structure, the two metal groups will be pointing up on wedged bonds, right? And that would indicate the same structure, right. So whether we get wedges or dashes, it doesn't matter because that's the same structure. It has an internal plane of symmetry, meaning we have identified the structure needed. Let's go ahead and label the structure and conclude the video. Thank you for watching.

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1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

10. Addition Reactions

Hydrogenation

Organic Chemistry

10. Addition Reactions

Hydrogenation

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Problem 60

Textbook Question

Draw the structure of a compound with molecular C₈H₁₄ that reacts with one equivalent of H₂ over Pd/C to form a meso compound

Verified step by step guidance

Step 1: Analyze the molecular formula C8H14. The degree of unsaturation can be calculated using the formula: \( ext{Degree of Unsaturation} = rac{2C + 2 - H}{2} \). For C8H14, \( ext{Degree of Unsaturation} = rac{2(8) + 2 - 14}{2} = 2 \). This indicates the presence of two double bonds, one triple bond, one ring and one double bond, or two rings in the structure.

Step 2: The problem states that the compound reacts with one equivalent of H2 over Pd/C to form a meso compound. This suggests that the compound contains a single double bond that can be hydrogenated, and the resulting product must have a plane of symmetry (a characteristic of meso compounds).

Step 3: To form a meso compound upon hydrogenation, the starting compound must have a symmetrical structure. A likely candidate is a compound with a double bond in a symmetrical position, such as a cis-alkene in a cyclic structure (e.g., a cycloalkene).

Step 4: Consider a symmetrical cyclic structure with one double bond, such as 1,2-cyclooctadiene. Upon hydrogenation, the double bond is reduced, and the resulting compound (cyclooctane) is meso because it has a plane of symmetry.

Step 5: Draw the structure of the compound. The starting compound is a symmetrical cycloalkene (e.g., cis-1,2-cyclooctadiene), and the product after hydrogenation is a meso compound (cyclooctane). Ensure the double bond is placed in a position that maintains symmetry in the starting structure.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Molecular Formula and Structure

The molecular formula C8H14 indicates a compound with eight carbon atoms and fourteen hydrogen atoms. Understanding how to derive the structural representation from this formula is crucial, as it helps in visualizing the compound's connectivity and functional groups. The structure must also accommodate the reactivity with hydrogen, suggesting the presence of unsaturation, such as double bonds or rings.

Hydrogenation Reaction

Hydrogenation is a chemical reaction where hydrogen (H2) is added to a compound, typically in the presence of a catalyst like palladium on carbon (Pd/C). This process is essential for converting unsaturated compounds into saturated ones. In this case, the reaction with one equivalent of H2 implies that the compound has at least one double bond that can be reduced, leading to the formation of a meso compound.

Meso Compounds and Symmetry

Meso compounds are achiral molecules that contain multiple stereocenters but possess an internal plane of symmetry. This symmetry allows for superimposition of the molecule on its mirror image, which is a key characteristic of meso compounds. When drawing the structure, it is important to ensure that the resulting product after hydrogenation exhibits this symmetry, confirming its classification as a meso compound.

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