Assign relative priorities to each set of substituents: b. -CH 2 CH 2 OH, -OH, -CH 2 Cl, -CH=CH 2

All right. Hi everyone. So for this question, it's ranked from lowest to highest the relative priorities of the substitution given below. So before I begin, let's recall that the relative priority of a substitute wint is determined by the atomic number of the atom directly bonded to the sp two carbon of your all keen, right? So what that means is that the higher the atomic number or A M for short, the higher the priority for your substitution. So if we go ahead and we look at each of our substitue ints and we notice what atoms are directly attached to the rest of our molecule are all keen, will realize that they're all carbon, right? So carbon has an atomic number of six and all of them have carbon as the attachment point of your substitution. So there's not really much information you can gain based on that, right, in terms of priority. So that's why in this situation where you're at um directly connected to your sp two carbon of your all keen is the same. You go ahead and you look at the next atom over. So if we look at this first substitute print on the very left side, this ether will notice that the carbon is directly attached to an oxygen And oxygen recall has an atomic number of eight. So let's keep that in mind when we make the rest of our comparisons, right? So if we look at the next substitution over, we'll see that carbon is instead bonded to borrowing which has an atomic number of 35. Now, this third substitute here has a carbon bonded to another carbon. So this other carbon is going to have an atomic number of six just like every other carbon, right? But now last but not least we have this amino group at the end of our final substitution here on the right side. So this nitrogen attached to our carbon has an atomic number of seven. And so now because we went one carbon over, we have a difference in atomic number. So now we can go ahead and assign priorities and like we mentioned before, the higher the atomic number, the higher priority. So what that means is that if we're going from lowest to highest, if I make a list here, going from the lowest first, then this substitue in with our two carbons is going to have the lowest priority because the next carbon over has an atomic number of six, which is the smallest one, right? So now the second place is going to be our amino group with an atomic number of seven. Mhm. And from there is oxygen Because that's an atomic number of eight And last but not least is our bombing, which is the highest priority by a long shot, right? Because that has an atomic number of 35. So that's going to be our highest. And so this order is going to correspond to option a in the multiple choice and that's going to be your final answer. So your main takeaway from this video should be that the relative priority of a substitution is determined normally by the atomic number of the atom directly connecting to the rest of your molecule or you're all keen in this case. But in situations like this where it's not possible to make a direct comparison based on that atom directly connected to your all keen, you have to determine the priority based on the next atom over which is what we did here. So with that being said, thank you very much for watching and I hope you found this helpful.

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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

4. Alkanes and Cycloalkanes

Cis vs Trans

Organic Chemistry

4. Alkanes and Cycloalkanes

Cis vs Trans

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4:25 minutes

Problem 8b

Textbook Question

Assign relative priorities to each set of substituents:
b. -CH₂CH₂OH, -OH, -CH₂Cl, -CH=CH₂

Verified step by step guidance

Step 1: Understand the concept of assigning priorities using the Cahn-Ingold-Prelog (CIP) priority rules. These rules are based on atomic number, connectivity, and the presence of double or triple bonds. Higher atomic numbers take precedence, and if the first atom is the same, you move outward to the next atoms in the substituent chain.

Step 2: Analyze the substituents provided: -CH2CH2OH, -OH, -CH2Cl, and -CH=CH2. Begin by comparing the first atom directly attached to the main chain for each substituent. For -CH2CH2OH, -CH2Cl, and -CH=CH2, the first atom is carbon (C), while for -OH, the first atom is oxygen (O). Since oxygen has a higher atomic number (8) than carbon (6), -OH is assigned the highest priority.

Step 3: For the remaining substituents (-CH2CH2OH, -CH2Cl, -CH=CH2), compare the atoms directly bonded to the first carbon. For -CH2CH2OH, the second atom is another carbon bonded to an oxygen (O). For -CH2Cl, the second atom is chlorine (Cl). For -CH=CH2, the second atom is carbon involved in a double bond. Chlorine has the highest atomic number among these, so -CH2Cl is assigned the next highest priority.

Step 4: Compare the remaining substituents (-CH2CH2OH and -CH=CH2). For -CH2CH2OH, the second carbon is bonded to an oxygen atom, while for -CH=CH2, the second carbon is part of a double bond. A double bond is treated as if the carbon is bonded to two additional carbons, which increases its priority. Therefore, -CH=CH2 is assigned the next highest priority.

Step 5: Assign the lowest priority to -CH2CH2OH, as its second carbon is bonded to an oxygen atom, which is less significant in priority compared to the double bond in -CH=CH2. The final order of priorities is: 1) -OH, 2) -CH2Cl, 3) -CH=CH2, 4) -CH2CH2OH.

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Key Concepts

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

Substituent Priority in Organic Chemistry

In organic chemistry, substituent priority is determined by the Cahn-Ingold-Prelog (CIP) priority rules, which assign priorities based on atomic number and connectivity. Higher atomic numbers take precedence, and if two substituents are identical, the next atoms in the chain are considered. This is crucial for determining stereochemistry and reactivity in organic molecules.

Functional Groups

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. In the given question, -OH (hydroxyl) and -CH2Cl (chloromethyl) are functional groups that influence the properties and reactivity of the compounds. Understanding these groups helps in predicting how different substituents will interact.

Double Bonds and Their Impact

Double bonds, such as those found in alkenes like -CH=CH2, significantly affect the reactivity and stability of organic compounds. They introduce geometric isomerism and can influence the overall priority of substituents due to their electron-rich nature. Recognizing the presence of double bonds is essential for accurately assigning priorities among substituents.

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