Give the structures of compounds A through B in the following series of reactions. <IMAGE>

Welcome back everyone to another video, identify the areas of high and low electron density in the compounds below using resonance structures. And we're given two examples. So let's begin. First of all, we're going to look at the first example. And what we notice is that the first example contains two carbon fragments, right? We have two carbonel functional groups. And this tells us that if we have pi bonds present, we can possibly deal with resonance structures. What we notice is that the car bono group has one sigma and one pi bond, we can always break our pi bond and delocalized those electrons in the form of a long pair on an electron atom such as oxygen. So this gives us our next resonance structure. Let's go ahead and draw it out if we place those electrons onto oxygen, oxygen is going to become electron ridge, right? And it is going to get a formal negative charge leaving carbon electron deficient. So carbon gets a formal positive charge and we can see the same with the other carbel right. We can essentially break the pi bond and shift the long pair of electrons on to oxygen, which essentially gives us our third resonance structure. Even though these are not stable, we are just interested in the formal positive and formal negative charges. So we're going to leave it as they are. We're not interested in major resonance contributors, right? And now let's go ahead and look at the second example before we answer the main question, what we notice is that we are given oxygen and en energy and pi bond electrons shift from high electron density to low electron density. So what we're going to do here essentially take the long pair of oxygen and form a pi bond out of it by breaking the adjacent pipe bond and forming a long pair on carbon. Let's go ahead and to the second resonance form based on the arrows. What we're noticing is that we are getting oxygen with a total of three bonds. And that means oxygen gets a formal positive charge and carbon with the resultant long pair of electrons gets a formal negative charge. And these formal charges essentially tell us which areas are high and low electron density areas. When we go back to the first example, we notice that both oxygen atoms have formal negative charges, right. So we can essentially tell that those are high electron density areas because there's a formal negative charge within our resonance form. So let's introduce the labels. We're going to show two arrows and state that the t oxygen atoms are high electron density areas. And what we notice is that the two carbon atoms from the car bono groups are low electron density areas because they have normal positive charges. Coming to the second example, we noticed that oxygen has a formal positive charge. So it is it is electron density area and the formal negative charge belongs to the double bonded carbon, meaning it is a high electron density area. So we have our answers. Let's label them and conclude the video. Thank you for watching.

Give the structures of compounds A through B in the following ser...

1. A Review of General Chemistry5h 5m

2. Molecular Representations1h 14m

3. Acids and Bases2h 46m

4. Alkanes and Cycloalkanes4h 19m

5. Chirality3h 39m

6. Thermodynamics and Kinetics1h 22m

7. Substitution Reactions1h 48m

8. Elimination Reactions2h 30m

9. Alkenes and Alkynes2h 9m

10. Addition Reactions3h 18m

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 Acids3h 20m

30. Peptides and Proteins2h 42m

31. Catalysis in Organic Reactions1h 30m

32. Lipids 2h 50m

34. Nucleic Acids1h 32m

35. Transition Metals5h 33m

36. Synthetic Polymers1h 49m

My Courses

Chemistry

Biology

Math

Physics

Business

Social Sciences

Programming

Product & Marketing

Give the structures of compounds A through B in the following series of reactions.

<IMAGE>