Cambrian Explosion, Complex Eukaryotic Organism, Ozonosphere 3

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1 Reporter: Wang Yuefan Reporter: Wang Yuefan Supervisor: Prof. Yang Zhen Supervisor: Prof. Yang Zhen Prof. Chen Jiahua Prof. Chen Jiahua

2 Content Preface Nature of oxygen species Electron reduced processes Summary & Outlook 2

3 Preface Cambrian Explosion, Complex Eukaryotic Organism, Ozonosphere 3

4 What is Dioxygen Activation? As the electronegativity of oxygen is just smaller than fluorine, the concept of dioxygen activation is that oxygen reduces to combine with carbon, hydrogen and other elements in a controllable manner. Energy Element 4

5 Content Preface Nature of oxygen species Electron reduced processes Summary & Outlook 5

6 Dioxygen Molecular l Orbital 1 g approximately 22.5 kcal/mol above the ground state triplet 6

7 Formal Pericyclic Reactions [4+2] cycloaddition Ene reaction [2+2] cycloaddition Clennana, E. L. Tetrahedron 2000, 59, Clennana, E. L.; Pace A. Tetrahedron 2005, 61, Alberti, M. N.; Orfanopoulos, M. Synlett 2010,

8 How Super is Superoxide Sawyer. D. T.; Valentine, J. S. Acc. Chem. Res. 1981, 14,

9 How Super is Superoxide Fluoride-like like forming exceptionally strong HB with water Though moderate acid, the tendency of O - 2- to disproportionate dominat reaction Oxidant via H-atom transfer from the reductant (flavins, hydrophenazines and hydroxylamine) Excellent coordinate unit and nucleophile in aprotic solvent Sawyer. D. T.; Valentine, J. S. Acc. Chem. Res. 1981, 14,

10 Nature of Hydrogenperoxide Weak acid, pka~12 HB with water, weaker than superoxide Strong oxidizer with an O-O single bond Nucleophile and chelation unit in basic condition Peroxide dianion should be stabilized by hydrogen or metal 10

11 Comparison between O - 2- and H 2 O 2 O 2- ~ strong base, H 2 O 2 ~ strong oxidizer Nucleophilic: O 2- rather than H 2 O 2 (HO 2- ) O 2- is hard to reduce unless stabilized by hydrogen or metal O 2 11

12 Content Preface Nature of oxygen species Electron reduced processes Summary & Outlook 12

13 Dioxygen Activation --- Fundamental Task for all Aerobic Organism Oxidative phosphorylation Oxygenase reactions Ideal oxidant in green chemistry Ideal oxygen source in synthetic chemistry 13

14 Multistep Electron Transfer 14

15 Multistep Electron Transfer Release the energy successively Lower the activation energy Kinetically favor 15

16 Superoxide Oxide Generation Sub-stable radical species would generate 16

17 Oxo-Species Induced O-Insertion Cytochrome P450: Fe heme monooxygenase reaction RH + O 2 + 2H + + 2e ROH + H 2 O 17

18 Oxo-Species Induced O-Insertion Cytochrome P450: Fe heme monooxigenase reaction RH + O 2 + 2H + + 2e ROH + H 2 O 18

19 Hydrogenperoxide Equivalent Naphthalene Dioxygenase Karlsson,A. et al. Science 2003, 299,

20 Dinuclear Stabled the Peroxide CH 4 + O 2 + NAD(P)H + H + -> CH 3 OH + NAD(P) + + H 2 O Methane monooxygenase Rosenzweig, A. C. et al. Nature ,

21 Delivery Superoxide to Radical Extradiol dioxygenase Costas, M. et al. Chem. Rev. 2004, 104, Kovaleva, E. G. et al. Acc. Chem. Res. 2007, 40,

22 Modes Activation Oxygen by Nature Oxidant via H- atom transfer from the reductant Tolman, W. B. et al. Nature 2008, 455,

23 Modes of Nature Activation Oxygen Multistep Electron Transfer Oxo-Species Induced O-Insertion and Epoxidation Hydrogenperoxide Equivalent Dinuclear Stabled the Peroxide Delivery Superoxide to Radical 23

24 Electron Reduced Process Inspiration from nature Electron transfer process Mimic the other mode of nature s method 24

25 Wacker Oxidation to MET 25

26 Wacker Oxidation Piera, J.; Bakvall, J. Angew. Chem. Int. Ed. 2008, 47,

27 Wacker Oxidation Piera, J.; Bakvall, J. Angew. Chem. Int. Ed. 2008, 47,

28 From Oxidative Addition to Inert Bond Activation Chen, X. et al. Angew. Chem. Int. Ed. 2009, 48,

29 Modes of Activation Oxygen Oxo-Species Induced Epoxidation and O-Insertion Copper Stabilized Superoxide Dinuclear Stabilized Peroxide Sub-stable Radical Attack to Dioxygen 29

30 Epoxidation Punniyamurthy, T.et al. Chem. Rev. 2005, 105,

31 Another Modification Carlton, L. et al. J. Chem. Soc., Chem. Commun. 1983, 586. Dobler, C. et al. Angew. Chem., Int. Ed. Engl. 1999, 38,

32 Oxo-species Induced O-Insertion (a) Alsters, P. L. et al. Organometallics 1993, 12, (b) Alsters, P. L. et al. Organometallics 1993, 12, R 1 = R 2 = H; Yield = 69% 32

33 Oxo-species Induced O-Insertion Zhang, Y.; Yu, J. J. Am. Chem. Soc. 2009, 131,

34 Modes of Activation Oxygen Oxo-Species Induced Epoxidation and O-Insertion Copper Stabilized Superoxide Dinuclear Stabilized Peroxide Sub-stable Radical Attack to Dioxygen 34

35 Copper Stabilized Superoxide Species Cu-Catalyzed Oxidative Amidation Diketonization of Terminal Alkynes Leading to -Ketoamides Zhang, C. et al. J. Am. Chem. Soc. 2010, 132, Zhang, C. et al. Angew. Chem. Int. Ed. 2011, 50,

36 Oxidation of Position of Imines Zhang, C. et al. Angew. Chem. Int. Ed. 2011, 50,

37 Oxidation of Position of Imines Wang, J. et al. Chem. Commun., 2011, 47,

38 Oxidation of Position of Enamines R 1 = R 2 = H; Yield = 69% Wang, H. et al. Angew. Chem. Int. Ed. 2011, 50,

39 Azide based One Electron Reduction Chiba, S. et al. J. Am. Chem. Soc. 2010, 132,

40 Modes of Activation Oxygen Oxo-Species Induced Epoxidation and O-Insertion Copper Stabilized Superoxide Dinuclear Stabilized Peroxide Sub-stable Radical Attack to Dioxygen 40

41 Dicopper Peroxo Complex R 1 = R 2 = H; Yield = 69% Lucas, H. R. et al. J. Am. Chem. Soc. 2009, 131,

42 Dicopper Peroxo Complex Unreactive in oxygen atom transfer reactions to common substrates R 1 = R 2 = H; Yield = 69% Garcia-Bosch, I. et al. Angew. Chem. Int. Ed. 2010, 49,

43 Dicopper Peroxo Complex 3 X (X=F, Me, H, and OMe) decomposition reveals that the corresponding catechol is formed in 34%, 34%, 36%, and 14% yields R 1 = R 2 = H; Yield = 69% Garcia-Bosch, I. et al. Angew. Chem. Int. Ed. 2010, 49,

44 Modes of Activation Oxygen Oxo-Species Induced Epoxidation and O-Insertion Copper Stabilized Superoxide Dinuclear Stabilized Peroxide Sub-stable Radical Attack to Dioxygen 44

45 Non-Copper based One Electron Reduction R 1 = R 2 = H; Yield = 69% Sun, Y. et al. Org. Lett. 2011, 13,

46 Non-Copper based One Electron Reduction Sun, Y. et al. Org. Lett. 2011, 13,

47 Non-Copper based One Electron Reduction Zhang, B. et al. Org. Lett. 2011, 13, R 1 = R 2 = H; Yield = 69% 47

48 Summary Multistep electron transfer Superoxide-metal species Ligand controlled binuclear system Superoxide generation in ETC 48

49 Summary One electron reduction Oxo-species induced O- insertion and epoxidation Dicopper based reduction 49

50 Outlook Electron reduced process is hot field in future How to control the radical formation?? Dinuclear peroxo complex modification Dioxygen activation is not the final target 50

51 Thank to Prof. Yang & Prof. Chen All the peoples help me & colleagues All members in our laboratory All the audience here 51

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