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Catellani Reaction. 2011.04.09. Contents. Introduction. Mechanism. Synthetic Applications. Conclusions. Introduction. The Nobel Prize in Chemistry 2010. Richard F Heack University of Delaware, Newark,DE,USA. Ei-ichi Negishi Purdu University, West Lafayetle,IN,USA. Akira Suzuki
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Catellani Reaction 2011.04.09
Contents Introduction Mechanism Synthetic Applications Conclusions
Introduction The Nobel Prize in Chemistry 2010 Richard F Heack University of Delaware, Newark,DE,USA Ei-ichi Negishi Purdu University, West Lafayetle,IN,USA Akira Suzuki Hokkaido University, Sapporo,Japan For palladium-catalyzed cross-coupling reactions in organic synthesis.
Introduction 1971,obtained Italian laurea under supervition of Prof. G. Casnati at the University of Parma . 1977,started to work on homogeneous Catalysis with group Ⅷ metals, G.Casnati Group 1978-1979, Postdoc, UC, Prof. J. Halpern 1989-1990, short periods in Sheffied,Tsukuba,Russia and China. 1990-present, full professor at Uiversity of Parma. Marta Catellani Catellani M, Angrew. Chem. Int. Ed.1997,36,119-122.
Introduction Role of Norbornene : 1. Essential for this reaction to occur; 2. Plays as a catalyst; 3. More than stoichiometric norbornene is necessary norbornene . . . Catellani Reaction is defined as Norbornene-mediated Ortho C-H Functionalization.
Mechanism R1= Alkyl, Aryl R2=Aryl, Alkenyl, H, CN R = H, or bulky substisuents
Oxidation Addition 1 Path 1 Path 2 R1=alkyl, path 1 predominates. R1=aryl , it depends on Ligands.
Carbopalladation of Norbornene Favored 1. High reactivity (strain energy 90.4 kJ/mol) 2. Superstoichiomeric quantities
Carbopalladation of Norbornene Phenylnorbornylpalladadium(Ⅱ) dimer PNP dimer Inoue M, Tedrahendron Lett.,1974(15),8,647-650. Catellani M, Angrew. Chem. Int. Ed.1997,36,119-122.
Palladacycle Formation 1.Inability of bicycle system for beta-Hybride elimination 2.Electrophilic aromatic substisution at ortho aromatic carbon Sicher J. Angrew. Chem. Int. Ed.1972,11,200-203
Palladacycle Formation EAS: rate limiting step. Wheland-type Intermediate ESA: electrophilic aromatic substitution Parshall G W. Acc Chem Res,1970(3),139-144. Markies BA. J Chem Soc Chem Commun ,1992, 1420-1423.
Palladacycle Formation Catellani M . J Organomet Chem ,1992, 425:151 Supports ESA for deprotonation is not rate limiting. Echavarren AM .Chem Eur J. 2001(7), 2341-2345.
Oxidative addition2 A side product ofen seen: X=Br, nd X=I, 62% Catellani M, Synthesis, 1996,769-772
Oxidative addition2 Addition with Alkyl Halides Ligand: 1,10-phenanthroline Catellani M, J Organomet Chem, 1993 .458:C12 80% ee 63%ee Lautens M. Angew Chem Int Ed,2007,1485-1488
Oxidative addition2 Addition with Aryl Halides Catellani Mechanism: Catellani M, J Organomet Chem, 1991 .407:C30 Echavarren Mechanism: Low energy Echavarren AM .J Am Chem Soc. 2006(128), 5033-5034.
Reductive Elimination sp2-sp3 bond formation Not observed Catellani M. J Organomet Chem,1990.390:251
Reductive Elimination sp2-sp2 bond formation The Ortho Effect Catellani M. J Organomet Chem,1991.407:C30
Norbornene Extrusion Characterized by NMR Steric factors! Lautens M .J Org Chem, 2009(74). 289-293
Mizoroki-Heck Intermolecular R3=alkyl Catellani M, Angrew. Chem. Int. Ed.1997,36,119-122. Mark. Lautens. Org Lett .2006,8,3939-3942.
Mizoroki-Heck Intermolecular Lautens M. Org Lett, 2003(5). 4827 Lautens M. Synlett, 2006. 2629 Lautens M. J Org Chem, 2007(72). 775 Lautens M. Angew Chem Int Ed, 2007(46). 1485
Mizoroki-Heck Intermolecular Oxyl-Micheal addition Catellani M, Org Lett. 2006(8). 3967 Catellani M, Synthesis. 2008. 995
Mizoroki-Heck Intramolecular Lautens M (2000) Angew Chem Int Ed 39:1045 Lautens M (2001) J Org Chem 66:8127 Lautens M (2005) Tetrahedron 61:6283 Lautens M (2002) J Org Chem 67:3972
Mizoroki-Heck Intramolecular Lautens M .Angew Chem Int Ed. 2007(46). 1485 Lautens M .J Org Chem. 2009(74). 289
Suzuki-Miyaura Catellani M. Chem Commun, 2000. 157 Catellani M. J Mol Catal A: Chem. 2003. 115
Cassar-Sonogashira ~50% Yield promoted By KOAc ,Excess alkyl halide Copper –free! Catellani M. J Organomet Chem. 2004. 689:3741
Cyanation Lautens M. JACS. 2006,128, 14436-14437; Zn(CN)2 K4Fe(CN)6 Lautens M . JACS. 2007,129, 15372-15372;
Direct Arylation C-H activation of arene is difficult Catellani reaction is a powful strategy for direact arylation. 60-94% Base effect:K2CO3&Bu4NBr >> Cs2CO3&KOAc Solvents :DMF>>DMA>>acetontrile Marta.Catellani. Org Lett. 2001,3611-3614.
Direct Arylation Mark Lautens. JACS,2005,13148; JOC,2008,1888; OL,2006,3601 OL, 2006,2043. Mark Lautens. JOC,2008,8705; OL,2006,4827
Buchwald-Hartwig Reaction Marta Catellani. OL. 2004,4759 Mark Lautens. OL. 2007,5255
Addition to C=O/C=N and C=C Bonds Mark Lautens. AICE. 2009,1849 Catellani M. Tetrahedron Lett, 2004(45),6903-6907.
Conclusions Catellani reaction is a useful and mechanistically interesting method for the polyfunctionalization of aromatic molecules.