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Literature Meeting - Charette Group – Marc K. Janes – December 6 th 2004

ACTIVATIONS BY HYDROGEN BONDING – SUCCESS STORIES. Viresh H. Rawal. Eric N. Jacobsen. 1986-1988 : Postdoctoral Fellow, MIT Professor K. Barry Sharpless 1982-1986 : University of California, Ph.D. Professor Robert G. Bergman 1978-1982 : New York University B.S. Professor Yorke E. Rhodes.

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Literature Meeting - Charette Group – Marc K. Janes – December 6 th 2004

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  1. ACTIVATIONS BY HYDROGEN BONDING – SUCCESS STORIES Viresh H. Rawal Eric N. Jacobsen 1986-1988: Postdoctoral Fellow, MIT Professor K. Barry Sharpless1982-1986: University of California, Ph.D.Professor Robert G. Bergman1978-1982: New York University B.S. Professor Yorke E. Rhodes Literature Meeting - Charette Group – Marc K. Janes – December 6th 2004

  2. ACTIVATIONS BY HYDROGEN BONDING – OUTLINE • The Hydrogen Bond • Acid catalysis (concepts) • Recent examples in organic chemistry • Seminal work (from hine to jacobsen) • Diels-Alders (Rawal) • Other reactions Literature Meeting - Charette Group – Marc K. Janes – December 6th 2004

  3. THE HYDROGEN BOND – DEFINITIONS • Pimentel and McClellan: • ‘’…a hydrogen bond exists • There is evidence of a bond • There is evidence that this bond sterically involves a hydrogen atom already bonded to another atom…’’. • Drawback: • May include van der Waals interactions and agostic interactions (3 center 2 electrons). • Proposed definition: • An X-H - - - A interaction is called a ‘’hydrogen bond’’: • It constitutes a local bond. • X-H acts as proton donor to A. • Etot = Eelectrostatic+ Epolarization + Echarge transfer + Edespersion • + Eexchange repulsion Steiner, ACIEE 2002, 48 (review)

  4. THE HYDROGEN BOND – A REVIEW Steiner, ACIEE 2002, 48 (review)

  5. THE HYDROGEN BOND – ENERGY IN GAS PHASE TO BE TAKEN WITH CAUTION NO MEDIUM EFFECT IN GAS PHASE IDEAL GEOMETRY WAS USED IN THE CALCULATIONS H-BONDS OFTEN FORM NETWORKS AND ARE NOT ADDITIVE (CANNOT SPLIT ENERGY ON EACH BOND) Steiner, ACIEE 2002, 48 (review)

  6. THE HYDROGEN BOND – A REVIEW Steiner, ACIEE 2002, 48 (review)

  7. THE HYDROGEN BOND – A REVIEW Steiner, ACIEE 2002, 48 (review)

  8. TYPES OF BRONSTED ACID CATALYSIS HYDROGEN BONDS ARE INVOLVED IN THE ACTIVATION OF THE SUBSTRATE AND THESE HYDROGENS ARE TRANSFERRED ONLY AT THE TRANSITION STATE

  9. THE BRONSTED CATALYSIS LAW Rate depends on [H3O+] : SAC Rate depends on [HA] : GAC

  10. MODES OF CARBONYL ACTIVATION BY COORDINATION Pihko, ACIEE 2004, 2062 (highlight)

  11. EXAMPLES OF INTERACTIONS Etter, JACS 1988, 5896; Acc. Chem. Res. 1990, 120. Kelly, TL 1990, 3381.

  12. EXAMPLES OF INTERACTIONS Radical allylation Curran, JOC 1994, 3259; TL 1995, 6647.

  13. JACOBSEN (SIGMAN) – STRECKER (must find a project that works…) Jacobsen, JACS 1998, 1401

  14. JACOBSEN (SIGMAN) - STRECKER Jacobsen, JACS 1998, 1401; ACIEE 2000, 1279

  15. JACOBSEN (SIGMAN) - STRECKER Jacobsen, ACIEE 2000, 1279

  16. JACOBSEN (SIGMAN) – STRECKER (MACHOISM) Jacobsen, ACIEE 2000, 1279

  17. JACOBSEN (SIGMAN) - STRECKER Jacobsen, ACIEE 2000, 1279

  18. JACOBSEN – STRECKER ON KETOIMINES 1c Jacobsen, OL 2000, 867

  19. JACOBSEN – REACTION KINETICS Model reaction Previously optimal catalyst Jacobsen, JACS 2002, 10012

  20. JACOBSEN – KINETIC STUDY OF UREA CATALYST INTERCEPT IS 1/vMAX Indicating that There is a VMAX Jacobsen, JACS 2002, 10012

  21. JACOBSEN – REACTION KINETICS CONCLUSIONS Model reaction Previously optimal catalyst • - 1st order in HCN and Catalyst • Saturation kinetics of imine (proven by Lineweaver Burk) • - Obeys Michaelis-Meten kinetics (steady state kinetics) • Implicates the reversible formation of an • IMINE – CATALYST COMPLEX Jacobsen, JACS 2002, 10012

  22. JACOBSEN – PROBES INTO BINDING (where are the interactions?) Jacobsen, JACS 2002, 10012

  23. JACOBSEN – BINDING STUDY OF UREA CATALYST Jacobsen, JACS 2002, 10012; SEE MARCELO IN JANUARY

  24. JACOBSEN – BINDING STUDY OF UREA CATALYST Jacobsen, JACS 2002, 10012; SEE MARCELO IN JANUARY

  25. JACOBSEN – BINDING STUDY OF UREA CATALYST 3 Jacobsen, JACS 2002, 10012

  26. JACOBSEN – IMINE GEOMETRY IN SOLUTION AND REACTIVE FORM ADDITION OF CATALYST Only the Z Interacts! Good reaction with fixed Z imine (ACIEE) Unreactive Fixed E imine Jacobsen, JACS 2002, 10012

  27. JACOBSEN – OUR FRIEND THE COMPUTER Solvent has little effect on solution phase structure (justification for gas phase approximation) Jacobsen, JACS 2002, 10012; SEE CLAUDE ANY TIME

  28. JACOBSEN – BINDING STUDY OF UREA CATALYST (1) The large group on the imine carbon is directed away from the catalyst and into solvent (Figure 1B); this serves to explain why 1 catalyzes hydrocyanation of most aldimines with high ee, regardless of the steric and electronic properties of the substrate. (2) The small group (H for aldimines, Me for methylketoimines) is aimed directly into the catalyst; ketoimines bearing larger substituents are poor substrates for the reaction,2c presumably because they cannot be accommodated within the optimal geometry. (3) The N-substituent is also directed away from the catalyst. However, its size is restricted as a result of the requirement to access the Z-isomer of the imine. (4) On the basis of the observed sense of stereoinduction, addition of HCN takes place over the diaminocyclohexane portion of the catalyst (i.e., from the right-hand side in Figure 1C) and away from the amino acid/amide portion. Adopts a well defined secondary structure in solution The last hypothesis leads to the prediction that increasing the steric properties of the amino acid/amide portion of the catalyst should lead to higher enantioselectivity in the hydrocyanation reactions. Jacobsen, JACS 2002, 10012

  29. JACOBSEN – UREA RATIONAL DESIGN Jacobsen, JACS 2002, 10012

  30. JACOBSEN – UREA RATIONAL DESIGN (MACHOISM) Jacobsen, JACS 2002, 10012

  31. JACOBSEN – MANNICH (NO STUDY) Jacobsen, JACS 2002, 12964

  32. JACOBSEN – HYDROPHOSPHONYLATION (NO STUDY) Jacobsen, JACS 2004, 4102

  33. JACOBSEN – HYDROPHOSPHONYLATION (NO STUDY) Jacobsen, JACS 2004, 4102

  34. JACOBSEN - PICTET-SPENGLER Jacobsen, JACS 2004, 10558.

  35. JACOBSEN - PICTET-SPENGLER (NO STUDY) Jacobsen, JACS 2004, 10558.

  36. JACOBSEN - PICTET-SPENGLER (NO STUDY) Jacobsen, JACS 2004, 10558.

  37. JORGENSEN – REVIEW ON HDA Warning, the following slide contains explicit content Jorgensen, ACIEE 2000, 3559

  38. JORGENSEN – REVIEW ON HDA Jorgensen, ACIEE 2000, 3559

  39. RAWAL – LEWIS ACID CATALYZED DA (SALEN-Cr) 1-amino-3-siloxy-1,3-butadienes Rawal JACS 2000, 7843; OL 2002, 1163; JACS 2002, 4628 (SUBTLE CHIRALITY)

  40. RAWAL - HDA OF UNACTIVATED KETONES Rawal, OL 2002, 3321 Rawal, JACS 2002, 4628 Rawal, JACS 2002, 4628

  41. RAWAL - REACTION OF UNACTIVATED KETONES Not due to prensence of DCl Rawal, OL 2002, 3321

  42. RAWAL – VERY REACTIVE DIENE Rawal, OL 2002, 3321; Jurczak, SYNTHESIS 1979, 41

  43. RAWAL – HDA SOLVENT SCAN Rawal, JACS 2002, 9662

  44. RAWAL - HDA OF UNACTIVATED KETONES Dihydropone Solvolysis Product : Rawal, JACS 2002, 9662

  45. RAWAL – FIRST GENERAL HDA FOR UNACTIVATED KETONES Rawal, JACS 2002, 9662

  46. MACMILLAN/HOUK/LIST – ORGANOCATALYSIS OTHER THAN H BOND MacMillan, JACS 2000, 4243; TL 2003, 2475 Houk-List, JACS 2003, 16; JACS 2003, 2475

  47. BRADDOCK – PHANOLS FOR DA (NOT ENANTIOSELECTIVE) Braddock, Synlett 2003, 1121

  48. GÖBEL – H BOND ASSISTED ASYMMETRIC DA Göbel, OL 2000, 179

  49. RAWAL - FIRST ASYMM. HDA THROUGH HYDROGEN BONDING Ar = 1-naphtyl Rawal, Nature 2003, 146

  50. RAWAL - ALL CARBON ASYMM. DA CAT. BY H-BONDING Rawal, PNAS 2004, 5846

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