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1 Ready; Catalysis Hydrogenation Categories and Dichotomies: Heterogeneous or Homogeneous Neutral or Cationic Directed or Non-directed Heterolytic or Homolytic H2 Activation Racemic or Enantioselective Syn or Trans Addition Homogeneous Hydrogenation Rh Ph3P Ph3P Cl PPh3 Advantages: Mild conditions Improved selectivity Directed Hydrogenation Enantioselective Hydrogenation Mechanistically accessible Disadvantages: Purification $$$$ Often less

Epoxidation, Dihydroxylation, and the Utility of Epoxides and Diols Ready Outline: Epoxidation Condensation approaches Darzens condensation Sulfur ylides With organic peroxides Peroxy acids Peroxy iminic acids Dioxiranes DMDO Enantioselective versions Metal-catalyzed Approaches V(O)(acac)2 Sharpless AE Metal Oxo’s MTO Fe, Pt and Mn-based (Salen)Mn Jacobsen AE Epoxide Ring Opening Opening under acid or basic conditions Organocopper additions Reactions of epoxy alcohols Dihydroxylation

Reagent/Reaction Use Ref Note DMSO/DCC (Pfitzner- Moffatt or Moffatt) Alcohol ketone/aldehyde Jacs 1963, 3027; Mech: JACS, 1965, 5561, JOC, 1967, 1926 First DMSO-based; DCC pain to remove; EDCI better DMSO/Ac2O “ Jacs 1967, 2416 DMSO/TFAA “ Jacs, 1975, 2758 DMSO/SO3-Pyridine (Parikh- Doering) “ JACS, 1967, 5505 Often under ambient conditions; best for α-chiral aldehydes/ketones (COCl)2/DMSO (swern) “ JOC, 1978, 2480; mech: Tet. 1978, 1651 Most commonly used; DMSO/Ac2O

Reactivity Umpolung-1 Ready Reactivity Umpolung: reversal of normal polarity electrophiles become nucleophiles nucleophiles become electrophiles Outline: 1. electrophilic heteroatoms 2. acyl anions 3. homoenolates 4. the cyclopropane trick 5. sulfone chemistry Normal reactivity: X x = heteroatom d = donor (Nu-) a = acceptor (E+) d a d a d X X X X or 1 3 1 5 How to make: X X or X X 1 2 1 4 complimentary

Oxidations at Carbon General references March, Advanced Org Chem, 1992, 1158-1238 Trost, Comp. Org. Syn. 1991, vol 7 Carey and Sundberg, Advanced Org Chem, part B, 615-664 Smith, Org Syn, Chap 3 H CH3 C(-IV) R CH3 C(-III) R CH2 OH C(-1) R CH OH RR H2 C R C(-II) R C O R C(0) R CH O C(+I) H CH2 OH C(-II) H CH O C(0) C(II) R COR O C(+III) H COH O C(+II) O C O C(+IV) RO COR O C(+IV) alkane RCH2M RCH2SiR3 RCH2X X=halide RCH2NR2 RCH2SR RCH2PR2 Acetal: RCH(OR)2

Ready; Catalysis Isomerization/cyclization-1 R M R' M R R' H R R' M H MH R R' H R' M M H Olefin insertion into Metal alkyl can be followed by hydride elimination or additional olefin insertions: -dimerization/oligomerization -small molecules -polymerization Recall: electron rich M (late transition metal) Keq < 1 ->dimerization, etc electron poor M (early transition metal) Keq > 1 ->polymerization P Ph2 Ni OO H C7-C14 C1-C3 HO C10-C18 C1-C3 C7-C14 Shell

• female • 20-40 years old • premenopausal You may be eligible for participation in a study on the role of obesity in Polycystic Ovarian Syndrome. Some compensation for participating in the study will be available. UNIVERSITY OF TEXAS SOUTHWESTERN MEDICAL CENTER We are conducting a study in body fat in women with clinical diagnosis of Polycystic Ovarian Syndrome. If you are: • female • 20-40 years old • premenopausal • healthy OR have a clinical diagnosis of

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