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Prerequisites: 333

www.chem.sc.edu/faculty/bryson/index.html. Linked to course syllabus and “ WEB PAGE ”. CHEM 334. Prerequisites: 333. synthesis. 29/32. Modified from sides of William Tam & Phillis Chang. Assignments. Due the second recitation:

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Prerequisites: 333

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  1. www.chem.sc.edu/faculty/bryson/index.html Linked to course syllabus and “WEB PAGE” CHEM 334 Prerequisites: 333 synthesis 29/32 Modified from sides of William Tam & Phillis Chang

  2. Assignments Due the second recitation: (1) Answer the following question in some detail. What study activity (activities) helped you the most in CHEM 333? (2) Complete review work sheet of 333 reactions.

  3. SYLLABUS “must read” (linked to the “Home” and WEB Page*) Text Solomons (10th ed) Schedule of tests and “projected” pace Honor code Policy - grading scale Recitation WEB PAGE Homework problems, aids, etc *www.chem.sc.edu/faculty/bryson/index.html

  4. Hydrogenation of “double bonds” olefins and carbonyls LiAlH4 NaBH4 Oxidation w/ PCC Oxidation w/ H2CrO4 and KMnO4 Organometallic compounds R-Li & RMgX Organometallics as bases Organometallics as Nu:(-) with: carbonyls epoxides esters Synthesis CHAPTER 12 Alcohols from Carbonyl Compounds Oxidation-Reduction Organometallic Compounds Srtucture of the carbonyl group C=O addition/ROH oxidation CHEM 334 Chapter 12

  5. Structure Carbonyl carbon: sp2 hybridized Planar structure Ch. 12 - 5

  6. Structure of the Carbonyl Group, Carbonyl compounds Others: Y = OH, OR’, NH2, X, etc. aldehyde alkanal ketone alkanone   Ch. 12 - 4

  7. Rxs of Carbonyl Compounds with Nucleophiles One of the most important reactions: nucleophilic addition to the carbonyl recall: Ch. 12 - 6

  8. Two important nucleophiles (bases): Hydrides (H:(-) from NaBH4 & LiAlH4 ) Carbanions (from R:(-)(+)Li & R:(-)(++)Mg(-)X ) Two important reactions: Ch. 12 - 7

  9. Oxidation-Reduction Rxs reduction: increase in hydrogen content or decrease in oxygen content oxygen content decreases carboxylic acid aldehyde hydrogen content decreases oxidation: increase in oxygen content or decrease in hydrogen content Ch. 12 - 8

  10. Alcohols by Reduction of Carbonyl Compounds Ch. 12 - 17

  11. Alcohols by Reduction of Carbonyl Compounds (1o alcohol) Ch. 12 - 18

  12. = Hydrides “LAH” LiAlH4 Nucleophilic and very basic React violently with H2O or protic sources Rxs in Et2O or THF, reduces all carbonyl groups less reactive & less basic than LiAlH4 uses protic solvent (e.g. EtOH) reduces only aldehydes and ketones NaBH4 Ch. 12 - 19

  13. Examples skip ether ex Ch. 12 - 23

  14. (neutralize) Mechanism Ch. 12 - 21

  15. Mechanism Esters (carboxylic acids) are reduced to 1o alcohols Ch. 12 - 22

  16. 3C. Summary of LiAlH4 and NaBH4 Reactivity reduced by LiAlH4 reduced by NaBH4 ease of reduction Ch. 12 - 24

  17. Oxidation of Alcohols special CrO3 reagents stronger oxidants Oxidation of Primary (1o) Alcohols Ch. 12 - 25

  18. Special CrO3 reagent = PCC Reagent pyridinium chlorochromate Ch. 12 - 26

  19. 3o 2o PCC oxidation 1o No Reaction Ch. 12 - 27

  20. Jones reagent Oxidation of 1o Alcohols to Carboxylic Acids Ch. 12 - 28

  21. Oxidation: CrO3 + H2SO4[or H2CrO4 ] [or KMnO4/HO(-)/Δ then H+/H2O] Ch. 12 - 29

  22. Organometallic Compounds organometallic compounds contain carbon-metal bonds Ch. 12 - 34

  23. Preparation of Organolithium &Organomagnesium Compounds Order of reactivity of RX RI > RBr > RCl Ch. 12 - 35

  24. Examples Ch. 12 - 36

  25. Rxs with Compounds Containing Acidic Hydrogens Grignard reagents and organolithium compounds are very strong bases Ch. 12 - 37

  26. + Mg2++ Br− Examples as base Ch. 12 - 38

  27. As nucleophiles:

  28. React as nucleophiles with epoxides Ch. 12 - 39

  29. Rxs of Grignard & Organolithium Reagentswith Carbonyls Ch. 12 - 41

  30. examples Ch. 12 - 44

  31. Reaction with esters 3o alcohol Ch. 12 - 45

  32. Mechanism Ch. 12 - 46

  33. Addition-Elimination Ch. 12 - 49

  34. Planning a Grignard [or RLi ] Synthesis Synthesis of Ch. 12 - 50

  35. Method 1 Retrosynthetic analysis Synthesis Ch. 12 - 51

  36. Method 2 Retrosynthetic analysis Synthesis Ch. 12 - 52

  37. Method 3 Retrosynthetic analysis Synthesis Ch. 12 - 53

  38. RMgX & RLi reagents cannot be prepared in the presence of the following groups because of reactions (acid-base or nucleophilic addition) : Ch. 12 - 56

  39. Sodium or Lithium Alkynides (acetylides) Preparation of lithium alkynides Reaction with aldehydes or ketones Ch. 12 - 58

  40. Synthesis and Protecting Groups Ch. 12 - 59

  41. disconnection Retrosynthetic analysis However Ch. 12 - 60

  42. Need to “protect” the –OH group first Ch. 12 - 61

  43. Synthesis Ch. 12 - 62

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