1. 1 Molecular and Gold Nanoparticles Supported N-Heterocyclic Carbene Silver(I) Complexes – Synthesis, Characterization and Catalytic Applications 學生 : 王趙增 指導老師 : 于淑君 博士 2009 / 07 / 20 Department of Chemistry & Biochemistry Chung Cheng University

2. 2 N-Heterocyclic Carbenes (NHC) NHCs are strongerσ-donors than the most electron rich phosphine - less likely to dissociate from the metal during the reaction NHCs have come to replace phosphines in many organometallic and organic reactions NHCs can be useful spectator ligands, tunable electronically and sterically NHCs are most frequently prepared via deprotonation of the corresponding azolium salts L-type two electrons

3. 3 N-Heterocyclic Carbenes as Ligands -In the early 90's NHC were found to have bonding properties similar to trialklyphosphanes( -PR 3 ) and alkylphosphinates ( -OP(OR)R 2 ). -compatible with both high and low oxidation state metals -examples: -reaction employing NHC's as ligands: Herrmann, W. Angew. Chem. Int. Ed. 2002, 41, 1290-1309. Herrmann, W. A.; Öfele, K; Elison, M.; Kühn, F. E.; Roesky, P. W. J. Organomet. Chem. 1994, 480, C7-C9.

4. 4 The Applications of Ag(I) NHC  Silver(I)-carbene complexes as carbene transfer agents  Addition of arenes to imines  Aza-Diels-Alder reaction  Asymmetric aldol reaction  Barbier-Grignard-type reaction

5. 5 The First Silver(I)-Carbene Complexes and The First Silver(I)-Carbene Complexes and Carbene-Copper(I) Complexes Arduengo A.J. et al. Organometallics 1993, 21, 3405-3409 Linear di-coordination

6. 6 Silver(I)-Carbene Complexes as Carbene Transfer Agents Wang, H. M. J. ; Lin, I. J. B. Organometallics 1998, 17, 972-975

7. 7 The trend of the bond energies for the metal fragments is AuCl > CuCl > AgCl Boehme, C. and Frenking, G. Organometallics 1998, 17, 5801-5809 Quantum Chemical Calculations for the N-Heterocyclic Carbene Complexes of MCl (M = Cu, Ag, Au)

8. 8 Motivation  Using NHCs ligand to replace phosphine ligand in organomatallic catalysis. organomatallic catalysis.  In comparison with other transition metals (Cu, Au), silver has been virtually untouched as a catalyst for coupling reactions.  To promote silver-catalyzed three-component coupling of aldehyde, alkyne, and amine.  Easy recovered effectivetly recycled Immobilization of NHC-Ag(I) complexs onto Au Nanoparticles. Immobilization of NHC-Ag(I) complexs onto Au Nanoparticles.

9. 9Experimental Preparation of [Ag(hmim) 2 ]PF 6 Complex

10. 10 Space linker synthesisExperimental Preparation of Au NPs-Ag(I)(NHC) 2 (PF 6 )

11. 11Experimental Preparation of Au NPs-Ag(I)(NHC) 2 (PF 6 )

12. 12 1 H NMR Spectra of [Hmim]HPF 6 and [Ag(hmim) 2 ]PF 6 2H

13. 13 c C *DMSO C 13 C NMR Spectra of [Hmim]HPF 6 and [Ag(hmim) 2 ]PF 6

14. 14 ESI-MS Spectrum of [Ag(hmim) 2 ]PF 6 Experimental MS Data Calculated MS Data

15. 15 IR Spectra of [Hmim]HPF 6 and [Ag(hmim) 2 ]PF 6 [Ag(hmim) 2 ]PF 6 a (hmim)HPF 6 b 1225 cm -1 1168 cm -1 NHC H-C-C & H-C-N bending

16. 16 UV Spectra of [Hmim]HPF 6 and [Ag(hmim) 2 ] PF 6 [ Ag(hmim) 2 ]PF 6 a (hmim) 2 PF 6 b b a π π* 210 nm

17. 17 Single-Crystal X-ray Structure of [Ag(hmim) 2 ]PF 6 bond lengths [Å] bond angles [deg] Ag(1)-C(1)2.083(3)C(2)-Ag(1)-C(11)177.16 Ag(1)-C(11)2.083(3)N(1)- C(1)-N(2)104.06 N(3)- C(11)-N(4)104.67 Dihedral Angle 1.802 o (221) π π interaction

18. 18 31 P NMR 19 F NMR 1 H, 31 P, and 19 F Spextra of Au-NPs- NHC Ligand *DMSO * -SH -CH 2 SH

19. 19 Synthesis of Au NPs-Ag(I)-(NHC) Complex Cross-link network structure

20. 20 1 H 2 H 31 P NMR 19 F NMR 1 H, 31 P, and 19 F ofAu NPs-Ag(I)-NHC Complex 1 H, 31 P, and 19 F of Au NPs-Ag(I)-NHC Complex *DMSO *

21. 21 1 H NMR Spectra of Ligand, Molcular and Au Nanoparticles *DMSO * * *

22. 22 Particle size 2.1 ± 1.12 nm Synthesis of Octanethiol Protected Au-SR NPs

23. 23 Particle size 3.1 ± 1.3 nm TEM Image and UV Spectrum of Au NPs-Immobilized (NHC) Ligand 230 nm Ligand centered π π*

24. 24 TEM Image and EDS of Au NPs-Ag(I) Complex Particle size: 2.1 ± 0.7 nm 245 nm

25. 25 IR Spectra of Ligand & Au Nanoparticles series SH stretching NHC H-C-C & H-C-N bending 1169 cm -1 1229 cm -1

26. 26 Aldehyde, Amine, and Alkyne-coupling Reactions (A 3 -Coupling) Have attracted much attention from organic chemists for the coupling products, propargylamines, which are major skeletons or synthetically versatile building blocks for the preparation of many nitrogen-containing biologically active compounds J. Org. Chem. 1995, 60, 1590-1594

27. 27 The First Silver-Catalyzed Three-Component Coupling of Aldehyde, Alkyne, and Amine Chao J. L. et. al. Org. Lett., Vol. 5, No. 23, 2003,4473-4475 EntryCatalyst (3 mol%)Time (h)Conversion (%) 1AgOTf1440 2AgBF 4 1435 3Ag 2 O1440 4Ag 2 SO 4 1442 5AgNO 3 1440 6AgF1440 7AgBr1455 8AgCl1460 9AgI1475

28. 28 Proposed Mechanism for the Three –Component Coupling Chao J. L. et. al. Org. Lett., Vol. 5, No. 23, 2003,4473-4475 C-H activation

29. 29 Reaction conditions: catalyst loading = 3 mol%; Benzaldehyde = 1.00 mmol; Pyperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol solvent = 1.0 mL EntrySolvent, TemperatureTimeConversion (%) a 1Propionitrile (97 o C)1hr91 2Acetonitril (83 o C)1hr73 3(hmim)Br1hr29 4(hmim)PF 6 1hr78 51,4-dioxane (105 o C)1hr20 6DMF (154 o C)1hr38 Ag(I)-Catalyzed A 3 -Coupling Reactions

30. 30 Ag(I)-Catalyzed A 3 -Coupling Reactions

31. 31 Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL EntryTime (h)Yield a (%) 10.593 20.592 30.595 40.595 50.593 A 3 -Coupling Reactions of Aliphaticaldehyde, Amine, and Alkyne

32. 32 EntryRTime (h)Yield a (%) 1H 0.5 1 2 91 95 98 2p-OMe 0.5 1 2 2.5 35 51 65 85 3p-Me265 4p-Cl 2 2.5 73 88 5o-Cl 2 2.5 3 68 75 83 A 3 -Coupling Reactions of Aromaticaldehyde, Amine, and Alkyne Reaction conditions: catalyst loading = 3 mol%; Benzaldehyde = 1.00 mmol; Pyperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol solvent = 1.0 mL

33. 33 EntryTime (min)Yield a (%) 13093 23095 33080 43093 A 3 -Coupling Reactions of para-Formaldehyde, Amine, and Alkyne Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL

34. 34 A 3 -Coupling Reactions of para-Formaldehyde, Amine, and Alkyne EntryTime (min)Yield a (%) 530 60 75 90 630 60 90 63 75 89 730 60 80 88 830 60 90 71 89 94 Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL

35. 35 EntryRTime (h)Yield a (%) 10.592 2 0.5 4 12 24 0 2 6 10 3 0.5 4 12 10 15 18 A 3 -coupling Reactions of Benzaldehyde, Amine, and Alkyne pKa 19.9 26.5 24 Reaction conditions: catalyst loading = 3 mol%; Benzaldehyde = 1.00 mmol; Pyperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol solvent = 1.0 mL

36. 36 Convection transition Thermal v.s. Microwave Heating Kappe, C. O. Angew. Chem. Int. Ed. 2004, 43, 6250-6284. microwavethermal

37. 37 Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL EntryTime (sec)Yield a (%) 14089 24095 33085 44092 A 3 -Coupling Reactions of Aliphaticaldehyde, Amine, and Alkyne

38. 38 EntryTime (sec)Yield a (%) 12089 22092 34090 42093 A 3 -coupling Reactions of para-Formaldehyde, Amine, and Alkyne Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL

39. 39 A 3 -Coupling Reactions of para-Formaldehyde, Amine, and Alkyne EntryTime (sec)Yield a (%) 53090 6 4085 720 80 8 3083 Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL

40. 40 EntryTime (sec)Yield a (%) 16089 26083 36078 A 3 -Coupling Reactions of Benzaldehyde, Amine, and Alkyne Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL

41. 41 Proposed Mechanism for the A 3 -Coupling Reaction

42. 42 A 3 -Coupling Reactions Catalyzed by a Reusable PS-supported Ag(I)-NHC complex Wang, Li. P.; Zhang, Y. L.; Wang M. Tetrahedron Letters 49 2008 6650–6654 1.Structure indefinite 2.Quantitative NHC-Silver (I) by ICP-Mass 24 h

43. 43 Au-[hmim] 2 AgPF 6 : 9 mg 1,2,4,5-tetramethylbenzene : 5 mg d 6 -DMSO 4 H 2 H 0.25 : 0.13 = X : 0.03725 X = 0. 07164 mmol – lignad 0.07164×0.5 = 0.0358 mmol- metal center 0.0358/9 = 0.004 mol/g Quantitative by NMR AA analysis: 0.0038 mol/g ICP-Mass anlysis: 0.0039 mol/g 需時 2 天 送校外 10 min

44. 44 Reaction conditions: Catalyst loading = 20 mol%; para-formaldehyde = 1.00 mmol; pyperidine = 1.10 mmol; phenylacetylene = 1.50 mmol propionitrile = 1.0 mL Recycle No. Time (h)Yield (%) 1293 2297 3296 4295 5293 6294 7292 8293 9291 10290 11290 12291 Reusable Au NPs-Ag(I)(NHC) 2 PF 6 Catalyst for A 3 -Coupling Reaction

45. 45 Reactivity Comparision Between Au NPs- Ag(I)(NHC)(PF 6 ) and [Ag(hmim) 2 ]PF 6 Entry Time (min) Cat. 3 Yield (%) Cat. 10 Yield (%) 1 10 20 30 65 83 95 83 92 > 99 2 10 20 30 52 78 93 44 67 88 3 10 20 30 68 81 93 61 77 91 4 10 20 30 69 82 92 58 74 93 Reaction conditions: catalyst loading = 1.5 mol%; Benzaldehyde = 1.00 mmol; Piperidine = 1.20 mmol; Phenylacetylene = 1.50 mmol; Propionitrile = 1.0 mL

46. 46Conclusions 1.The air- and water-stable catalyst [Ag(hmim) 2 ]PF 6 was synthesized and characterized by 1 H- and 13 C-NMR, ESI-MS, IR, UV, X-ray. 2.We have developed a methodology to successfully immobilize [Ag(hmim) 2 ]PF 6 onto surfaces of Au NPs. The structure of the supported Ag(I)-NHC complex catalyst was characterized by 1 H-NMR, IR, TEM, UV, EDS, AA, ICP-Mass. 3.Since the Au NPs- Ag(I) hybrid catalysts are highly soluble in organic solvents, their structures and reactions were studied by simple solution NMR technique. 4. We have successfully demonstrated the catalytic activity of the Ag(I) complex for the three-component coupling reactions of aldehyde, alkyne, and amine. 5. The Au NPs- Ag(I) catalyst can be quantitatively recovered and effectively reused for many times without any loss of reactivity.